Abstract

To meet the increasing needs of high-precision glass micro-optics and address the major limitations of current three-dimensional (3D) printing optics, we have developed a liquid, solvent-free, silica precursor and two-photon 3D printing process. The printed optical elements can be fully converted to transparent inorganic glass at temperatures as low as 600 C with a shrinkage rate of 17%. We have demonstrated the whole process, from material development, printing, and performance evaluation of the printed glass micro-optics. 3D printing of glass micro-optics with isotropic shrinkage, micrometer resolution, low peak-to-valley deviation (${\lt}100\;\rm nm$), and low surface roughness (${\lt}6\;\rm nm$) has been achieved. The reported technique will enable the rapid prototyping of complex glass micro-optics previously impossible using conventional glass optics fabrication processes.

© 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

1. INTRODUCTION

Due to their excellent optical, chemical, and thermal properties, inorganic glasses are widely used in industry, defense, space, and high-end consumer applications [1,2]. Conventional grinding and polishing methods are the standards for fabricating spherical, aspherical, and flat surfaces, but are slow and incapable of fabricating freeform surfaces [3,4]. In addition, traditional grinding and polishing are not suitable for fabricating glass micro-optics. Precision press molding is an efficient method for fabricating freeform optical elements, but, due to the time and cost of preparing high-precision molds, it is not suitable for rapid prototyping. Optical elements with microstructures, such as diffractive optical elements and gratings, are commonly formed with microlithography, etching, and molding. Although modern fabrication processes have achieved a high level of efficiency and reproducibility, novel strategies are still needed for making complex-shaped, especially microsized, glass optics [5].

Three-dimensional (3D) printing is attractive due to its flexibility in building complex shapes through an additive process. There are a number of reports using polymeric materials to print organic optics with decent performance by additive manufacturing [39]. However, organic optics printed by polymer-based components are limited in practical applications due to their poor thermal stability, low transmission in short wavelengths, and low refractive indices. 3D printing of inorganic optics has lagged because of the stringent requirements on surface shape, surface roughness, and homogeneity in optical properties, as well as a limited selection of printable optical materials. Direct printing transparent inorganic glass optics with laser sintering, fused filament deposition, direct ink writing (DIW), stereolithography (STL), projection microstereolithography (PµSL), or two-photon stereolithography (TPSL) has generally not achieved the quality required for optical applications [1014]. These approaches have been limited by shrinkage with burning out of organic components and high temperature sintering, defects (bubbles, hidden layers, etc.), and a limited range of materials. Fused glass filament deposition of inorganic glass fiber suffers from low print resolution due to the size of the filament [10,11]. DIW of nanocomposite suffers from large shrinkage, as ink solvent evaporates and sintering of suspended silica particles occurs [12,15,16]. STL, PµSL, and TPSL approaches using inorganic particles suspended in curable liquid organic resins are impeded by unacceptably high viscosities with higher particle loadings and shrinkage due to the burnout of organics and melting of the remaining particles into a glass [13,17]. Meanwhile, the nanocomposite may suffer from clusters of nanoparticles in the material, which can cause negative effects to the surface morphology and roughness. Some improvement is observed when the organic resin is replaced by an organosilicon analog that is converted into silica during the pyrolysis process, but the high shrinkage is still inevitable [14]. Some siloxane-based polymers have been used to fabricate polymer-derived ceramics, but the high percentage of organic groups makes them unsuitable to fabricate transparent glass with low shrinkage [18]. Considering that shrinkage is a central deterrent to successful 3D printing of inorganic glass optics, replacing the organic solvent with a low viscosity, liquid, inorganic resin would serve permit high resolution STL, PµSL, and TPSL printing with minimal shrinkage [11,12].

Here, we report a 3D printing approach of glass micro-optics with minimal shrinkage using a two-photon polymerization (TPP) process [Fig. 1(a)] and a photosensitive, liquid silica resin (LSR) based on precondensed silica used to prepare low-density silica aerogels [Fig. 1(b)] [19]. TPP is able to achieve a small volume curing and has been investigated extensively for high-resolution printing of optical elements based on liquid organic resins [3,9,20]. LSR is an oligomer derived from the acid-catalyzed hydrolysis and condensation of tetramethoxysilane and a small amount of methacryloxy-modified trimethoxysilane with a substoichiometric amount of water. Since we use a molecular level resin, we do not have the issue of particle cluster. Therefore, the proposed LSR has the potential to obtain glass optics with smoother surfaces. In addition, the proposed LSR has lower shrinkage due to the higher inorganic content before thermal treatment. Pyrolysis at 600°C followed by sintering at 1000°C can eliminate any residual organics and convert the cured resin to silica. Compared to the shrinkage from previous reports, which is usually from 30% to more than 60%, the LSR shows only 17% shrinkage with pyrolysis and only an additional 4% shrinkage with sintering [13,14]. Printing is carried out by direct writing in LSR on a quartz slide with a femtosecond 780 nm laser. We demonstrate that the glass microlens and gratings can be printed in high resolution. The surface of final glass optics can be precisely controlled with a peak to valley of ${\lt}100\;{\rm nm}$ and a surface roughness lower than 6 nm.

 figure: Fig. 1.

Fig. 1. Printing system and printing process. (a) Schematic diagram of the 3D printing system. M1 and M2 are the folding mirrors; ${{\rm L}_1}$ and ${{\rm L}_2}$ are the lenses for the beam expander; ${{\rm Obj}_1}$ and ${{\rm Obj}_2}$ are the microscope objectives for curing the material and monitoring the printing process, respectively; and BS is the beam splitter; (b) synthesis of LSR; (c) fabrication process of the glass micro-optics; (d) 3D printed glass micro-lens on supporting structure.

Download Full Size | PPT Slide | PDF

2. MONOMER CHOICE FOR SOLVENT-FREE LSR, PYROLYSIS, SINTERING, AND SHRINKAGE

It is essential to apply a thermally or photochemically curable liquid resin during SLA or DIW, which makes the printing of inorganic glass more difficult because most of the inorganic compounds tend to form solid. Organic liquid resins are low molecular weight oligomers with pendant monomer substituents that most commonly will cross-link with light- or heat-induced radical generation for initiators. These resins shrink little because a majority of the linkages between monomers are already in place, and only a few additional bonds are needed to connect all of the oligomers into a glassy solid.

For an inorganic oxide glass, the resin should have a significant portion of the M-O-M linkages already in place. Linear silicone oligomers have half Si-O-Si linkages needed for silica but possess at least 40 wt% organic groups. Conversion of silicones, with densities of $0.965{\rm \;g}/{{\rm mL}^3}$ to amorphous silica with a density of 2.26 g/mL would result in 68% shrinkage after oxidation and sintering. The Si-O-Si content can be increased with silsesquioxanes, ${{\rm RSiO}_{1.5}}$, but the ultimate liquid resin is the precondensed LSRs developed to create ultralow density aerogels [19,21]. Partial condensation of tetramethoxysilane (TMOS) replaces nearly all of the methoxide groups with Si-O-Si linkages in a branched and cyclic rich LSR that, if low enough in molecular weight, can remain liquid. For example, LSRs can be obtained with 27 wt% of TMOS in methanol with 1.5 eq water and HCl as catalyst. With 1.6 eq of water per mole of TMOS, a solid, but soluble, resin was obtained and with more than 1.6 eq of water, the resin irreversibly forms a gel [22]. Unfortunately, the pure TMOS-based LSRs did not cure with exposure to the UV. This was remedied by incorporating a small amount of 3-methacryloxypropyltrimethoxysilane (MPTS) or methacryloxymethyltrimethoxysilane (MMTS) into the hydrolysis and condensation reaction. Reacting TMOS and 6.5 mol% MMTS with 1.45 eq of water afforded an LSR with a viscosity suitable for printing [10131 mP-s, shear rate of $40{{\rm \;s}^{- 1}}$, [Fig. 2(a)]. 4-methoxyphenol (MEHQ) was added during the reaction to prevent the polymerization of MPTS or MMTS. Both Fourier-transform infrared (FTIR) spectroscopy and hydrogen nuclear magnetic resonance ($^{1}{\rm H}$ NMR) were used to demonstrate the presence of the methacrylate functional group after the synthesis [Figs. 2(b) and 2(c)]. The degree of condensation in the LSRs were verified by comparing the integrals of methyl peak from methyl methacrylate group (1.96 ppm) and methoxy peak (3.62 ppm) in $^{1}{\rm H}$ NMR [Fig. 2(c)]. Our precondensed LSRs have densities close to 1.5 g/mL (e.g.,  the LSR prepared with 6.5 mol% MMTS has a density of 1.48 g/mL), which is much closer than silicone resins to the density of amorphous silica. A photoinitiator (Bis(diethylamino)benzophenone) was dissolved into the synthesized LSR before TPP fabrication.

 figure: Fig. 2.

Fig. 2. Characterization of the LSR used for TPP. (a) Viscosity of the precursor prepared with 6.5 mol% of MMTS. The viscosity increased gradually as the shear rate increased from ${40^{- 1}}$ to ${120^{- 1}}$, indicating the precursor has a shear-thickening property; (b) Fourier transform infrared - attenuated total reflectance (FTIR-ATR) spectra of the printed sample before and after thermal treatment; (c) $^{1}{\rm H}$ NMR spectrum of LSR prepared with 1.45 eq of water and 6.5 mol% of MMTS. The integrals of peak a (1.96 ppm) and peak b (3.62 ppm) indicate that after the precondensation, there were around 5.3 methyl methacrylate groups per 100 methoxy groups; (d) TGA result of the cured sample prepared with 6.5 mol% of MMTS. The first mass drop, which started around 130°C, indicates the starting of condensation of the -OMe group; (e) process of heating treatment. The heating ramp before 200°C was controlled as 1°C/min, and the ramp after 200°C was controlled as 0.5°C/min. The holdings at 160°C and 200°C were aimed to finish the condensation of the -OMe group.

Download Full Size | PPT Slide | PDF

To obtain inorganic glass elements, 3D printed samples were heated at 600°C and then 1000 C. Based on the thermal gravimetric analysis (TGA) result [Figs. 2(d) and 2(e)], residual methanol and water are lost at around 100°C, followed by loss of methanol and water from methoxide group and silanol condensation reactions and oxidation of the organic substituents [10]. Above 570°C, there was little change in mass. Change in chemical composition of the printed samples was monitored through thermal treatment using FTIR. While the FTIR spectrum of LSR showed peaks from hydrocarbons ($2832{-}3050{{\rm \;cm}^{- 1}}$, $1465{{\rm \;cm}^{- 1}}$) and methacrylate C = O ($1725{{\rm \;cm}^{- 1}}$), spectra of the thermally treated printed sample after 600°C and 1000°C exhibited only peaks from Si-O ($927{-}1300{{\rm \;cm}^{- 1}}$) characteristic of silica and trace amounts of absorbed water (${\sim}1610{{\rm \;cm}^{- 1}}$) [Fig. 2(b)]. At this point, the material is inorganic silica of excellent transparency consistent with a nonporous glass, but with significantly lower temperatures than other reported 3D printing approaches. The refractive index of the printed glass after 600°C treatment is $1.46 \pm 0.01$ at 632.8 nm.

With 12 mol% of the MPTS, 26% shrinkage was observed in the printed sample with pyrolysis. When MPTS was reduced to 6.5 mol%, the shrinkage after 600 °C decreased to 19%. Additional reduction in shrinkage was afforded by switching from the propylene tether in MPTS between the methacryloxy and the trimethoxysilane groups to a shorter methylene in MMTS. Glass ring [Fig. 3(a)] printed using an LSR prepared with 6.5 mol% of MMTS exhibited only 17% linear shrinkage after being heated at 600°C for 3 h [Fig. 3(b)]. After being heated to 1000°C for another 3 h, only another 4% shrinkage was observed [Fig. 3(c)]. Figure 3(d) is the measured shrinkage rate of the printed part after treatment from 200 to 1000. Reducing the MMTS to 3 mol% provided insignificant difference to shrinkage ($\le\! 1{\rm \%}$). Besides, we noticed that at 3 mol%, the concentration of methacrylate attached to the oligomeric silica was too low (only 3 methacrylates per 100 Si atoms) to effectively cross-link the LSR. Thus, LSR prepared with 6.5 mol% MMTS was used in this study.

 figure: Fig. 3.

Fig. 3. Shrinkage after thermal treatment. The sample was printed with LSR prepared with 6.5 mol% MMTS. (a)–(c) are the SEM images of the ring as-printed, after 600°C and 1000 C treatment; (d) shrinkage rate after heat treatment from 200°C to 1000°C.

Download Full Size | PPT Slide | PDF

Another phenomenon that has been noticed is that the condensation of the as-printed objects without thermal treatment underwent about 8% linear shrinkage after two months’ storage in the air at room temperature, which is probably caused by the moisture from air [14]. However, this will not affect the overall shrinkage after thermal treatment compared to the as-printed status.

3. OPTIMIZATION OF THE PRINTING PARAMETERS AND PRINTING RESOLUTION

In order to optimize the printing process, an array of thin squares was printed on a quartz substrate with a range of laser pulse energies (0.89–1.62 nJ) and exposure times (0.2–100 s). The exposure time here was the total time for printing each square. Figure 4(a) is the SEM image of a region of printed square arrays, and Fig. 4(b) is the surface profile measured with a white-light interference microscope. Figure 4(c) shows the distribution of the heights of the printed squares for different laser pulse energies and exposure times. It is clear that the thickness increased as the pulse energy increased and/or exposure time increased, meaning that the axis resolution of the printing system could be well controlled by the laser pulse energy or exposure time [23]. While the higher pulse energy may improve the printing speed, it also can generate enough methanol or water vapor from the curing chemistry to form bubbles. One more important finding was that the layer thickness was saturated to 5.2 µm even when a longer exposure time (${\gt}\!100\;{\rm s}$) was applied. With a 1.25 NA objective, 780 nm fs laser, 0.89 nJ pulse energy, and ${\sim}0.2{\rm \;s}$ exposure time, the smallest printed dot was about 560 nm diameter [Fig. 4(d)], which indicated the submicrometer printing resolution can be achieved.

 figure: Fig. 4.

Fig. 4. Evaluation of the printing performance of the material prepared with 6.5 mol% of MMTS. All the samples were measured before thermal treatment. (a) SEM image of 3D printed squares (scale bar = 25 µm); (b) surface profile of the array of squares printed with different laser pulse energies and exposure times; (c) distribution of the heights of printed squares; (d) SEM image of the smallest cured dots (560 nm diameter) for evaluating the printing resolution.

Download Full Size | PPT Slide | PDF

 figure: Fig. 5.

Fig. 5. Evaluation of material shrinkage with different geometric shapes. (a) Microscopic image of the printed grating array after sintering at 1000°C and (b) the grating profiles and SEM images of the four gratings in (a).

Download Full Size | PPT Slide | PDF

4. PRINTED GLASS MICRO-OPTICS AND THEIR PERFORMANCE

With the information gained from the study discussed in Fig. 4, a number of different micro-optics were directly printed on the quartz substrate to demonstrate the printing capability. However, due to the thermal expansion of the substrate and the shrinkage of the printed element, as well as the friable nature of the prints, cracks were observed during the thermal treatment process, especially for the elements with large aspect ratios or with large contact area with the substrate. Deformation at the edges were also observed even when no crack was observed. To address this critical issue, the contact area between the printed structure and substrate was reduced by preprinting the supporting structures.

Figure 5(a) is a grating array with four different grating profiles [semisphere, rectangle, isosceles trapezoid, and right-angle trapezoid, as shown in Fig. 5(b)]. The gratings were printed on a platform that was supported by several pillars. The shapes of the gratings were measured with a Zygo Newview 8300 optical profilometer before and after thermal treatment. Compared to the design profiles, the gratings were printed accurately except for some minor errors around the corners. After the thermal treatment at 1000°C, the grating shrank isotropically, and the measured shrinkage rate was $21 \pm 0.5{\rm \%}$. It should be pointed out that there were some misalignments between the measured grating profiles in Fig. 5(b) for each grating because two measurements were made before and after thermal treatment, and so the orientation and the position of the line profiles were not the exactly the same.

A plano–convex microlens with a radius of 25 µm was printed on the top four preprinted pillars, as shown in Fig. 6(a). Based on the linear shrinkage (17% at 600°C), the radius curvature of the lens was printed as 29.25 µm to compensate for the shrinkage. RMS surface roughness was 5.65 nm [Fig. 6(b)]. Surface deviation from the ideal lens surface in the central region was less than ${\pm} 50{\rm \;nm}$ [Fig. 6(c)]. To evaluate the imaging performance of the printed microlens, a $40{\times}$, 0.6 NA microscope objective was used to observe the intermediate image formed by the printed microlens [Fig. 6(d)]. Figures 6(e) and 6(f) are the images of the first element in Group 7 in 1951 USAF resolution target for the printed microlens after thermal treatment at 600 C and 1000 C, demonstrating the printed glass lens has a great potential for imaging application. Since the microlens was not designed to correct aberrations under the experimental condition in Fig. 6(d), the image was not diffraction-limited.

 figure: Fig. 6.

Fig. 6. Performance of printed microlens and grating. (a) Microlens printed on supporting pillars (treated at 600°C); (b) and (c) surface profile of the printed lens and the deviation from the design; (d) diagram of experimental setup for evaluating the imaging performance; (e) image of the first element in Group 7 in 1951 USAF resolution target for the printed lens after thermal treatment at 600 C; (f) image of the first element in Group 7 in 1951 USAF resolution target for the printed lens after thermal treatment at 1000°C; (g) SEM images of a printed grating after thermal treatment at 600°C and (h) diffraction pattern for a 632.8 nm laser beam.

Download Full Size | PPT Slide | PDF

A single diffraction grating was also manufactured. Figure 6(g) shows the SEM images of the grating with right-triangle profile with the period of 15 µm and height of 8.5 µm. Figure 6(h) is the diffraction pattern for the collimated 632.8 nm laser beam from the grating. The central bright spot is observed because the laser beam was larger than the grating.

5. CONCLUSION

In summary, we have developed solvent-free, methacryloxy-modified LSRs and TPP-based 3D printing for glass micro-optics. The modification of LSR with as little as 6.5 mol% MMTS significantly reduces the organic component and shrinkage with pyrolysis. Transparent glass optics can be obtained after thermal treatment at 600°C with shrinkage as low as 17%, which was also demonstrated to be isotropic. With the preprinted supporting structure, deformation and damage of the printed optics during thermal treatment can be avoided. Glass microlenses and gratings were successfully fabricated, and the optical performance were evaluated. The peak-to-valley surface deviation is lower than 1/6 ${\lambda}$ (${\lambda } = 632.8{\rm \;nm}$), and the RMS surface roughness is lower than 6 nm.

Our current printing process of micro-optics was achieved using LSR prepared with 6.5 mol% MMTS. When a larger lens or multilens system is desired, tuning the ratio of MMTS may still be required to reach a higher cross-linking density to get better mechanical properties during/after printing. Therefore, it is necessary to optimize the LSR for a better balance between shrinkage and printability. The printing parameters should also be further optimized for different LSRs to optimize the resolution as well as printing speed. In the meantime, materials with higher refractive indices and larger dispersion should be developed for better control of monochromatic and chromatic aberrations.

Disclosures

The authors declare no conflicts of interest.

Data availability

Data underlying the results presented in this paper are not publicly available at this time but may be obtained from the authors upon reasonable request.

REFERENCES

1. K. Lu and M. K. Mahapatra, “Network structure and thermal stability study of high temperature seal glass,” J. Appl. Phys. 104, 074910 (2008). [CrossRef]  

2. A. J. Ikushima, T. Fujiwara, and K. Saito, “Silica glass: a material for photonics,” J. Appl. Phys. 88, 1201–1213 (2000). [CrossRef]  

3. T. Gissibl, S. Thiele, A. Herkommer, and H. Giessen, “Two-photon direct laser writing of ultracompact multi-lens objectives,” Nat. Photonics 10, 554–560 (2016). [CrossRef]  

4. N. Vaidya and O. Solgaard, “3D printed optics with nanometer scale surface roughness,” Microsystems Nanoeng. 4, 18 (2018). [CrossRef]  

5. T. J. Suleski and R. D. Te Kolste, “Fabrication trends for free-space microoptics,” J. Lightwave Technol. 23, 633–646 (2005). [CrossRef]  

6. X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018). [CrossRef]  

7. B. G. Assefa, M. Pekkarinen, H. Partanen, J. Biskop, J. Turunen, and J. Saarinen, “Imaging-quality 3D-printed centimeter-scale lens,” Opt. Express 27, 12630–12637 (2019). [CrossRef]  

8. G. Shao, R. Hai, and C. Sun, “3D printing customized optical lens in minutes,” Adv. Opt. Mater. 8, 1901646 (2020). [CrossRef]  

9. P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018). [CrossRef]  

10. J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015). [CrossRef]  

11. J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017). [CrossRef]  

12. D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017). [CrossRef]  

13. F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017). [CrossRef]  

14. D. G. Moore, L. Barbera, K. Masania, and A. R. Studart, “Three-dimensional printing of multicomponent glasses using phase-separating resins,” Nat. Mater. 19, 212–217 (2020). [CrossRef]  

15. J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018). [CrossRef]  

16. R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020). [CrossRef]  

17. F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021). [CrossRef]  

18. Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016). [CrossRef]  

19. T. M. Tillotson, L. W. Hrubesh, and I. M. Thomas, “Partially hydrolyzed alkoxysilanes as precursors for silica aerogels,” MRS Proc. 121, 685–689 (1988). [CrossRef]  

20. S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017). [CrossRef]  

21. R. H. Baney, M. Itoh, A. Sakakibara, and T. Suzuki, “Silsesquioxanes,” Chem. Rev. 95, 1409–1430 (1995). [CrossRef]  

22. T. M. Tillotson and L. W. Hrubesh, “Transparent ultralow-density silica aerogels prepared by a two-step sol-gel process,” J. Non-Cryst. Solids 145, 44–50 (1992). [CrossRef]  

23. K. Takada, H. B. Sun, and S. Kawata, “Improved spatial resolution and surface roughness in photopolymerization-based laser nanowriting,” Appl. Phys. Lett. 86, 071122 (2005). [CrossRef]  

References

  • View by:
  • |
  • |
  • |

  1. K. Lu and M. K. Mahapatra, “Network structure and thermal stability study of high temperature seal glass,” J. Appl. Phys. 104, 074910 (2008).
    [Crossref]
  2. A. J. Ikushima, T. Fujiwara, and K. Saito, “Silica glass: a material for photonics,” J. Appl. Phys. 88, 1201–1213 (2000).
    [Crossref]
  3. T. Gissibl, S. Thiele, A. Herkommer, and H. Giessen, “Two-photon direct laser writing of ultracompact multi-lens objectives,” Nat. Photonics 10, 554–560 (2016).
    [Crossref]
  4. N. Vaidya and O. Solgaard, “3D printed optics with nanometer scale surface roughness,” Microsystems Nanoeng. 4, 18 (2018).
    [Crossref]
  5. T. J. Suleski and R. D. Te Kolste, “Fabrication trends for free-space microoptics,” J. Lightwave Technol. 23, 633–646 (2005).
    [Crossref]
  6. X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
    [Crossref]
  7. B. G. Assefa, M. Pekkarinen, H. Partanen, J. Biskop, J. Turunen, and J. Saarinen, “Imaging-quality 3D-printed centimeter-scale lens,” Opt. Express 27, 12630–12637 (2019).
    [Crossref]
  8. G. Shao, R. Hai, and C. Sun, “3D printing customized optical lens in minutes,” Adv. Opt. Mater. 8, 1901646 (2020).
    [Crossref]
  9. P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
    [Crossref]
  10. J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
    [Crossref]
  11. J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
    [Crossref]
  12. D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
    [Crossref]
  13. F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
    [Crossref]
  14. D. G. Moore, L. Barbera, K. Masania, and A. R. Studart, “Three-dimensional printing of multicomponent glasses using phase-separating resins,” Nat. Mater. 19, 212–217 (2020).
    [Crossref]
  15. J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
    [Crossref]
  16. R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
    [Crossref]
  17. F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
    [Crossref]
  18. Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
    [Crossref]
  19. T. M. Tillotson, L. W. Hrubesh, and I. M. Thomas, “Partially hydrolyzed alkoxysilanes as precursors for silica aerogels,” MRS Proc. 121, 685–689 (1988).
    [Crossref]
  20. S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017).
    [Crossref]
  21. R. H. Baney, M. Itoh, A. Sakakibara, and T. Suzuki, “Silsesquioxanes,” Chem. Rev. 95, 1409–1430 (1995).
    [Crossref]
  22. T. M. Tillotson and L. W. Hrubesh, “Transparent ultralow-density silica aerogels prepared by a two-step sol-gel process,” J. Non-Cryst. Solids 145, 44–50 (1992).
    [Crossref]
  23. K. Takada, H. B. Sun, and S. Kawata, “Improved spatial resolution and surface roughness in photopolymerization-based laser nanowriting,” Appl. Phys. Lett. 86, 071122 (2005).
    [Crossref]

2021 (1)

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

2020 (3)

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

D. G. Moore, L. Barbera, K. Masania, and A. R. Studart, “Three-dimensional printing of multicomponent glasses using phase-separating resins,” Nat. Mater. 19, 212–217 (2020).
[Crossref]

G. Shao, R. Hai, and C. Sun, “3D printing customized optical lens in minutes,” Adv. Opt. Mater. 8, 1901646 (2020).
[Crossref]

2019 (1)

2018 (4)

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

N. Vaidya and O. Solgaard, “3D printed optics with nanometer scale surface roughness,” Microsystems Nanoeng. 4, 18 (2018).
[Crossref]

2017 (4)

J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017).
[Crossref]

2016 (2)

Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
[Crossref]

T. Gissibl, S. Thiele, A. Herkommer, and H. Giessen, “Two-photon direct laser writing of ultracompact multi-lens objectives,” Nat. Photonics 10, 554–560 (2016).
[Crossref]

2015 (1)

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

2008 (1)

K. Lu and M. K. Mahapatra, “Network structure and thermal stability study of high temperature seal glass,” J. Appl. Phys. 104, 074910 (2008).
[Crossref]

2005 (2)

T. J. Suleski and R. D. Te Kolste, “Fabrication trends for free-space microoptics,” J. Lightwave Technol. 23, 633–646 (2005).
[Crossref]

K. Takada, H. B. Sun, and S. Kawata, “Improved spatial resolution and surface roughness in photopolymerization-based laser nanowriting,” Appl. Phys. Lett. 86, 071122 (2005).
[Crossref]

2000 (1)

A. J. Ikushima, T. Fujiwara, and K. Saito, “Silica glass: a material for photonics,” J. Appl. Phys. 88, 1201–1213 (2000).
[Crossref]

1995 (1)

R. H. Baney, M. Itoh, A. Sakakibara, and T. Suzuki, “Silsesquioxanes,” Chem. Rev. 95, 1409–1430 (1995).
[Crossref]

1992 (1)

T. M. Tillotson and L. W. Hrubesh, “Transparent ultralow-density silica aerogels prepared by a two-step sol-gel process,” J. Non-Cryst. Solids 145, 44–50 (1992).
[Crossref]

1988 (1)

T. M. Tillotson, L. W. Hrubesh, and I. M. Thomas, “Partially hydrolyzed alkoxysilanes as precursors for silica aerogels,” MRS Proc. 121, 685–689 (1988).
[Crossref]

Arnold, K.

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Arzenbacher, K.

S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017).
[Crossref]

Assefa, B. G.

Baney, R. H.

R. H. Baney, M. Itoh, A. Sakakibara, and T. Suzuki, “Silsesquioxanes,” Chem. Rev. 95, 1409–1430 (1995).
[Crossref]

Barbera, L.

D. G. Moore, L. Barbera, K. Masania, and A. R. Studart, “Three-dimensional printing of multicomponent glasses using phase-separating resins,” Nat. Mater. 19, 212–217 (2020).
[Crossref]

Bauer, W.

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Baumann, T. F.

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Billah, M.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Biskop, J.

Blaicher, M.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Bristow, D. A.

J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
[Crossref]

Caer, C.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Carter, W. B.

Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
[Crossref]

Chen, X.

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

Colombo, P.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Dangel, R.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Dave, S.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Destino, J. F.

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Dietrich, P. I.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Dong, B.

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

Dudukovic, N. A.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Duoss, E. B.

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Dylla-Spears, R.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Eckel, Z. C.

Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
[Crossref]

Egan, G. C.

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

Franchin, G.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Freude, W.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Fujiwara, T.

A. J. Ikushima, T. Fujiwara, and K. Saito, “Silica glass: a material for photonics,” J. Appl. Phys. 88, 1201–1213 (2000).
[Crossref]

Giessen, H.

S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017).
[Crossref]

T. Gissibl, S. Thiele, A. Herkommer, and H. Giessen, “Two-photon direct laser writing of ultracompact multi-lens objectives,” Nat. Photonics 10, 554–560 (2016).
[Crossref]

Gilbert, L. J.

J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
[Crossref]

Gissibl, T.

S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017).
[Crossref]

T. Gissibl, S. Thiele, A. Herkommer, and H. Giessen, “Two-photon direct laser writing of ultracompact multi-lens objectives,” Nat. Photonics 10, 554–560 (2016).
[Crossref]

Hai, R.

G. Shao, R. Hai, and C. Sun, “3D printing customized optical lens in minutes,” Adv. Opt. Mater. 8, 1901646 (2020).
[Crossref]

Helmer, D.

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Herkommer, A.

T. Gissibl, S. Thiele, A. Herkommer, and H. Giessen, “Two-photon direct laser writing of ultracompact multi-lens objectives,” Nat. Photonics 10, 554–560 (2016).
[Crossref]

Herkommer, A. M.

S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017).
[Crossref]

Herrera, O. D.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

Hofmann, A.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Hoose, T.

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Houk, P.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Hrubesh, L. W.

T. M. Tillotson and L. W. Hrubesh, “Transparent ultralow-density silica aerogels prepared by a two-step sol-gel process,” J. Non-Cryst. Solids 145, 44–50 (1992).
[Crossref]

T. M. Tillotson, L. W. Hrubesh, and I. M. Thomas, “Partially hydrolyzed alkoxysilanes as precursors for silica aerogels,” MRS Proc. 121, 685–689 (1988).
[Crossref]

Ikushima, A. J.

A. J. Ikushima, T. Fujiwara, and K. Saito, “Silica glass: a material for photonics,” J. Appl. Phys. 88, 1201–1213 (2000).
[Crossref]

Inamura, C.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Itoh, M.

R. H. Baney, M. Itoh, A. Sakakibara, and T. Suzuki, “Silsesquioxanes,” Chem. Rev. 95, 1409–1430 (1995).
[Crossref]

Jacobsen, A. J.

Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
[Crossref]

Johnson, M. A.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

Kawata, S.

K. Takada, H. B. Sun, and S. Kawata, “Improved spatial resolution and surface roughness in photopolymerization-based laser nanowriting,” Appl. Phys. Lett. 86, 071122 (2005).
[Crossref]

Kayser, M.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Keller, N.

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Kinzel, E. C.

J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
[Crossref]

Klein, J.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Koos, C.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Kotz, F.

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Landers, R. G.

J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
[Crossref]

Lee, J.

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

Liu, W.

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

Lu, K.

K. Lu and M. K. Mahapatra, “Network structure and thermal stability study of high temperature seal glass,” J. Appl. Phys. 104, 074910 (2008).
[Crossref]

Luo, J.

J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
[Crossref]

Mahapatra, M. K.

K. Lu and M. K. Mahapatra, “Network structure and thermal stability study of high temperature seal glass,” J. Appl. Phys. 104, 074910 (2008).
[Crossref]

Martin, J. H.

Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
[Crossref]

Martin, T.

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

Masania, K.

D. G. Moore, L. Barbera, K. Masania, and A. R. Studart, “Three-dimensional printing of multicomponent glasses using phase-separating resins,” Nat. Mater. 19, 212–217 (2020).
[Crossref]

Meyers, C.

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Moehrle, M.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Moore, D. G.

D. G. Moore, L. Barbera, K. Masania, and A. R. Studart, “Three-dimensional printing of multicomponent glasses using phase-separating resins,” Nat. Mater. 19, 212–217 (2020).
[Crossref]

Nargang, T. M.

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Nguyen, D. T.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Offrein, B.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Ortega, J. M.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

Oxman, N.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Partanen, H.

Pekkarinen, M.

Qu, C.

J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
[Crossref]

Quick, A. S.

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

Rapp, B. E.

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Reuter, I.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Richter, C.

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Risch, P.

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

Ryerson, F. J.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

Saarinen, J.

Sachsenheimer, K.

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Saito, K.

A. J. Ikushima, T. Fujiwara, and K. Saito, “Silica glass: a material for photonics,” J. Appl. Phys. 88, 1201–1213 (2000).
[Crossref]

Sakakibara, A.

R. H. Baney, M. Itoh, A. Sakakibara, and T. Suzuki, “Silsesquioxanes,” Chem. Rev. 95, 1409–1430 (1995).
[Crossref]

Sasan, K.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

Sawvel, A. M.

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

Schaedler, T. A.

Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
[Crossref]

Schild, D.

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Shao, G.

G. Shao, R. Hai, and C. Sun, “3D printing customized optical lens in minutes,” Adv. Opt. Mater. 8, 1901646 (2020).
[Crossref]

Smay, J. E.

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Solgaard, O.

N. Vaidya and O. Solgaard, “3D printed optics with nanometer scale surface roughness,” Microsystems Nanoeng. 4, 18 (2018).
[Crossref]

Steele, W. A.

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

Stern, M.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Studart, A. R.

D. G. Moore, L. Barbera, K. Masania, and A. R. Studart, “Three-dimensional printing of multicomponent glasses using phase-separating resins,” Nat. Mater. 19, 212–217 (2020).
[Crossref]

Suleski, T. J.

Sun, C.

G. Shao, R. Hai, and C. Sun, “3D printing customized optical lens in minutes,” Adv. Opt. Mater. 8, 1901646 (2020).
[Crossref]

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

Sun, H. B.

K. Takada, H. B. Sun, and S. Kawata, “Improved spatial resolution and surface roughness in photopolymerization-based laser nanowriting,” Appl. Phys. Lett. 86, 071122 (2005).
[Crossref]

Suratwala, T.

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Suzuki, T.

R. H. Baney, M. Itoh, A. Sakakibara, and T. Suzuki, “Silsesquioxanes,” Chem. Rev. 95, 1409–1430 (1995).
[Crossref]

Takada, K.

K. Takada, H. B. Sun, and S. Kawata, “Improved spatial resolution and surface roughness in photopolymerization-based laser nanowriting,” Appl. Phys. Lett. 86, 071122 (2005).
[Crossref]

Te Kolste, R. D.

Thiel, M.

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

Thiele, S.

S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017).
[Crossref]

T. Gissibl, S. Thiele, A. Herkommer, and H. Giessen, “Two-photon direct laser writing of ultracompact multi-lens objectives,” Nat. Photonics 10, 554–560 (2016).
[Crossref]

Thomas, I. M.

T. M. Tillotson, L. W. Hrubesh, and I. M. Thomas, “Partially hydrolyzed alkoxysilanes as precursors for silica aerogels,” MRS Proc. 121, 685–689 (1988).
[Crossref]

Tillotson, T. M.

T. M. Tillotson and L. W. Hrubesh, “Transparent ultralow-density silica aerogels prepared by a two-step sol-gel process,” J. Non-Cryst. Solids 145, 44–50 (1992).
[Crossref]

T. M. Tillotson, L. W. Hrubesh, and I. M. Thomas, “Partially hydrolyzed alkoxysilanes as precursors for silica aerogels,” MRS Proc. 121, 685–689 (1988).
[Crossref]

Troppenz, U.

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Turunen, J.

Vaidya, N.

N. Vaidya and O. Solgaard, “3D printed optics with nanometer scale surface roughness,” Microsystems Nanoeng. 4, 18 (2018).
[Crossref]

Ware, H. O. T.

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

Weaver, J. C.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Wong, L. L.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

Yang, M.

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Yee, T. D.

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

Zhang, H. F.

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

Zhou, C.

Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
[Crossref]

Zhu, C.

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

3D Print. Addit. Manuf. (1)

J. Klein, M. Stern, G. Franchin, M. Kayser, C. Inamura, S. Dave, J. C. Weaver, P. Houk, P. Colombo, M. Yang, and N. Oxman, “Additive manufacturing of optically transparent glass,” 3D Print. Addit. Manuf. 2, 93–105 (2015).
[Crossref]

Adv. Mater. (3)

D. T. Nguyen, C. Meyers, T. D. Yee, N. A. Dudukovic, J. F. Destino, C. Zhu, E. B. Duoss, T. F. Baumann, T. Suratwala, J. E. Smay, and R. Dylla-Spears, “3D-printed transparent glass,” Adv. Mater. 29, 1701181 (2017).
[Crossref]

F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, and B. E. Rapp, “Two-photon polymerization of nanocomposites for the fabrication of transparent fused silica glass microstructures,” Adv. Mater. 33, 2006341 (2021).
[Crossref]

X. Chen, W. Liu, B. Dong, J. Lee, H. O. T. Ware, H. F. Zhang, and C. Sun, “High-speed 3D printing of millimeter-size customized aspheric imaging lenses with sub 7 nm surface roughness,” Adv. Mater. 30, 1705683 (2018).
[Crossref]

Adv. Mater. Technol. (1)

J. F. Destino, N. A. Dudukovic, M. A. Johnson, D. T. Nguyen, T. D. Yee, G. C. Egan, A. M. Sawvel, W. A. Steele, T. F. Baumann, E. B. Duoss, T. Suratwala, and R. Dylla-Spears, “3D printed optical quality silica and silica–titania glasses from sol–gel feedstocks,” Adv. Mater. Technol. 3, 1700323 (2018).
[Crossref]

Adv. Opt. Mater. (1)

G. Shao, R. Hai, and C. Sun, “3D printing customized optical lens in minutes,” Adv. Opt. Mater. 8, 1901646 (2020).
[Crossref]

Appl. Phys. Lett. (1)

K. Takada, H. B. Sun, and S. Kawata, “Improved spatial resolution and surface roughness in photopolymerization-based laser nanowriting,” Appl. Phys. Lett. 86, 071122 (2005).
[Crossref]

Chem. Rev. (1)

R. H. Baney, M. Itoh, A. Sakakibara, and T. Suzuki, “Silsesquioxanes,” Chem. Rev. 95, 1409–1430 (1995).
[Crossref]

J. Appl. Phys. (2)

K. Lu and M. K. Mahapatra, “Network structure and thermal stability study of high temperature seal glass,” J. Appl. Phys. 104, 074910 (2008).
[Crossref]

A. J. Ikushima, T. Fujiwara, and K. Saito, “Silica glass: a material for photonics,” J. Appl. Phys. 88, 1201–1213 (2000).
[Crossref]

J. Lightwave Technol. (1)

J. Manuf. Sci. Eng. Trans. ASME (1)

J. Luo, L. J. Gilbert, C. Qu, R. G. Landers, D. A. Bristow, and E. C. Kinzel, “Additive manufacturing of transparent soda-lime glass using a filament-fed process,” J. Manuf. Sci. Eng. Trans. ASME 139, 061006 (2017).
[Crossref]

J. Non-Cryst. Solids (1)

T. M. Tillotson and L. W. Hrubesh, “Transparent ultralow-density silica aerogels prepared by a two-step sol-gel process,” J. Non-Cryst. Solids 145, 44–50 (1992).
[Crossref]

Microsystems Nanoeng. (1)

N. Vaidya and O. Solgaard, “3D printed optics with nanometer scale surface roughness,” Microsystems Nanoeng. 4, 18 (2018).
[Crossref]

MRS Proc. (1)

T. M. Tillotson, L. W. Hrubesh, and I. M. Thomas, “Partially hydrolyzed alkoxysilanes as precursors for silica aerogels,” MRS Proc. 121, 685–689 (1988).
[Crossref]

Nat. Mater. (1)

D. G. Moore, L. Barbera, K. Masania, and A. R. Studart, “Three-dimensional printing of multicomponent glasses using phase-separating resins,” Nat. Mater. 19, 212–217 (2020).
[Crossref]

Nat. Photonics (2)

T. Gissibl, S. Thiele, A. Herkommer, and H. Giessen, “Two-photon direct laser writing of ultracompact multi-lens objectives,” Nat. Photonics 10, 554–560 (2016).
[Crossref]

P. I. Dietrich, M. Blaicher, I. Reuter, M. Billah, T. Hoose, A. Hofmann, C. Caer, R. Dangel, B. Offrein, U. Troppenz, M. Moehrle, W. Freude, and C. Koos, “In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration,” Nat. Photonics 12, 241–247 (2018).
[Crossref]

Nature (1)

F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, and B. E. Rapp, “Three-dimensional printing of transparent fused silica glass,” Nature 544, 337–339 (2017).
[Crossref]

Opt. Express (1)

Sci. Adv. (2)

R. Dylla-Spears, T. D. Yee, K. Sasan, D. T. Nguyen, N. A. Dudukovic, J. M. Ortega, M. A. Johnson, O. D. Herrera, F. J. Ryerson, and L. L. Wong, “3D printed gradient index glass optics,” Sci. Adv. 6, eabc7429 (2020).
[Crossref]

S. Thiele, K. Arzenbacher, T. Gissibl, H. Giessen, and A. M. Herkommer, “3D-printed eagle eye: compound microlens system for foveated imaging,” Sci. Adv. 3, e1602655 (2017).
[Crossref]

Science (1)

Z. C. Eckel, C. Zhou, J. H. Martin, A. J. Jacobsen, W. B. Carter, and T. A. Schaedler, “Additive manufacturing of polymer-derived ceramics,” Science 351, 58–62 (2016).
[Crossref]

Data availability

Data underlying the results presented in this paper are not publicly available at this time but may be obtained from the authors upon reasonable request.

Cited By

OSA participates in Crossref's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (6)

Fig. 1.
Fig. 1. Printing system and printing process. (a) Schematic diagram of the 3D printing system. M1 and M2 are the folding mirrors; ${{\rm L}_1}$ and ${{\rm L}_2}$ are the lenses for the beam expander; ${{\rm Obj}_1}$ and ${{\rm Obj}_2}$ are the microscope objectives for curing the material and monitoring the printing process, respectively; and BS is the beam splitter; (b) synthesis of LSR; (c) fabrication process of the glass micro-optics; (d) 3D printed glass micro-lens on supporting structure.
Fig. 2.
Fig. 2. Characterization of the LSR used for TPP. (a) Viscosity of the precursor prepared with 6.5 mol% of MMTS. The viscosity increased gradually as the shear rate increased from ${40^{- 1}}$ to ${120^{- 1}}$, indicating the precursor has a shear-thickening property; (b) Fourier transform infrared - attenuated total reflectance (FTIR-ATR) spectra of the printed sample before and after thermal treatment; (c) $^{1}{\rm H}$ NMR spectrum of LSR prepared with 1.45 eq of water and 6.5 mol% of MMTS. The integrals of peak a (1.96 ppm) and peak b (3.62 ppm) indicate that after the precondensation, there were around 5.3 methyl methacrylate groups per 100 methoxy groups; (d) TGA result of the cured sample prepared with 6.5 mol% of MMTS. The first mass drop, which started around 130°C, indicates the starting of condensation of the -OMe group; (e) process of heating treatment. The heating ramp before 200°C was controlled as 1°C/min, and the ramp after 200°C was controlled as 0.5°C/min. The holdings at 160°C and 200°C were aimed to finish the condensation of the -OMe group.
Fig. 3.
Fig. 3. Shrinkage after thermal treatment. The sample was printed with LSR prepared with 6.5 mol% MMTS. (a)–(c) are the SEM images of the ring as-printed, after 600°C and 1000 C treatment; (d) shrinkage rate after heat treatment from 200°C to 1000°C.
Fig. 4.
Fig. 4. Evaluation of the printing performance of the material prepared with 6.5 mol% of MMTS. All the samples were measured before thermal treatment. (a) SEM image of 3D printed squares (scale bar = 25 µm); (b) surface profile of the array of squares printed with different laser pulse energies and exposure times; (c) distribution of the heights of printed squares; (d) SEM image of the smallest cured dots (560 nm diameter) for evaluating the printing resolution.
Fig. 5.
Fig. 5. Evaluation of material shrinkage with different geometric shapes. (a) Microscopic image of the printed grating array after sintering at 1000°C and (b) the grating profiles and SEM images of the four gratings in (a).
Fig. 6.
Fig. 6. Performance of printed microlens and grating. (a) Microlens printed on supporting pillars (treated at 600°C); (b) and (c) surface profile of the printed lens and the deviation from the design; (d) diagram of experimental setup for evaluating the imaging performance; (e) image of the first element in Group 7 in 1951 USAF resolution target for the printed lens after thermal treatment at 600 C; (f) image of the first element in Group 7 in 1951 USAF resolution target for the printed lens after thermal treatment at 1000°C; (g) SEM images of a printed grating after thermal treatment at 600°C and (h) diffraction pattern for a 632.8 nm laser beam.

Metrics