Abstract

In this paper, we propose a replication method of thermoplastic polymer spherical lens array using a novel microforged mold. The Si3N4 ceramic balls, with 3.5 mm diameter, 10 nm surface roughness and 84 nm deviation from spherical profile, were utilized as indentor to generate aluminum alloy lens array mold. Upon the optimization of technical parameters, such as heating and de-molding temperature, indentation force and holding time, a high quality spherical lens array mold was obtained. The mold was used to fabricate spherical PMMA lens array by hot embossing, which showed excellent characteristics on dimensional stability, surface features and optical performances. Especially for the requirements of deep sag height and low f/#, the microforging technique reveals superior performance for low cost and high quality manufacture of spherical lenses. Compared to the previous complicated tools which requires precise calibration, the self-alignment mode of the balls and cavities can easily guarantee positioning accuracy. Accordingly, the pre-milled spherical cavity deformed uniformly in the process of microforging due to the symmetrical distribution of contact pressure and reduced the error caused by deformation. We believe the proposed microforging technique is an ideal mass production approach to the fabrication of thermoplastic polymer spherical lens array.

© 2016 Optical Society of America

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References

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  1. M. Sokuler, D. Aronov, G. Rosenman, and L. A. Gheber, “Tailored polymer microlenses on treated glass surfaces,” Appl. Phys. Lett. 90(20), 203106 (2007).
    [Crossref]
  2. L. Li and A. Y. Yi, “Design and fabrication of a freeform microlens array for a compact large-field-of-view compound-eye camera,” Appl. Opt. 51(12), 1843–1852 (2012).
    [Crossref] [PubMed]
  3. D. Xie, H. Zhang, X. Shu, and J. Xiao, “Fabrication of polymer micro-lens array with pneumatically diaphragm-driven drop-on-demand inkjet technology,” Opt. Express 20(14), 15186–15195 (2012).
    [Crossref] [PubMed]
  4. Z. Zang, X. Tang, X. Liu, X. Lei, and W. Chen, “Fabrication of high quality and low cost microlenses on a glass substrate by direct printing technique,” Appl. Opt. 53(33), 7868–7871 (2014).
    [Crossref] [PubMed]
  5. C. Y. Chang, S. Y. Yang, and M. H. Chu, “Rapid fabrication of ultraviolet-cured polymer microlens arrays by soft roller stamping process,” Microelectron. Eng. 84(2), 355–361 (2007).
    [Crossref]
  6. D. Xie, X. Chang, X. Shu, Y. Wang, H. Ding, and Y. Liu, “Rapid fabrication of thermoplastic polymer refractive microlens array using contactless hot embossing technology,” Opt. Express 23(4), 5154–5166 (2015).
    [Crossref] [PubMed]
  7. X. Zhu, L. Zhu, H. Chen, L. Yang, and W. Zhang, “Micro-ball lens structure fabrication based on drop on demand printing the liquid mold,” Appl. Surf. Sci. 361, 80–89 (2016).
    [Crossref]
  8. H. Yang, C. K. Chao, M. K. Wei, and C. P. Lin, “High fill-factor microlens array mold insert fabrication using a thermal reflow process,” J. Micromech. Microeng. 14(8), 1197–1204 (2004).
    [Crossref]
  9. C. Peng, X. G. Liang, Z. L. Fu, and S. Y. Chou, “High fidelity fabrication of microlens arrays by nanoimprint using conformal mold duplication and low-pressure liquid material curing,” J. Vac. Sci. Technol. 25(2), 410–414 (2007).
    [Crossref]
  10. M. Chakrabarti, C. Dam-Hansen, J. Stubager, T. F. Pedersen, and H. C. Pedersen, “Replication of optical microlens array using photoresist coated molds,” Opt. Express 24(9), 9528–9540 (2016).
    [Crossref] [PubMed]
  11. X. Zhu, H. Chen, L. Zhu, H. Wang, and W. Zhang, “Fabrication of curved microlens array using a drop-on-demand droplet generator and polydimethylsiloxane replica mold,” Opt. Eng. 53(11), 117109 (2014).
    [Crossref]
  12. S. Moon, S. Kang, and J. U. Bu, “Fabrication of polymeric microlens of hemispherical shape using micromolding,” Opt. Eng. 41(9), 2267–2270 (2002).
    [Crossref]
  13. L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
    [Crossref]
  14. B. McCall and T. S. Tkaczyk, “Fabrication of plastic microlens array for array microscopy by three-dimensional diamond micromilling,” Opt. Eng. 49(10), 103401 (2010).
    [Crossref] [PubMed]
  15. B. McCall and T. S. Tkaczyk, “Rapid fabrication of miniature lens arrays by four-axis single point diamond machining,” Opt. Express 21(3), 3557–3572 (2013).
    [Crossref] [PubMed]
  16. C. R. Forest, M. A. Saez, and I. W. Hunter, “Microforging technique for rapid, low-cost fabrication of lens array molds,” Appl. Opt. 46(36), 8668–8673 (2007).
    [Crossref] [PubMed]
  17. J. Pribošek and J. Diaci, “Electromagnetic microforging apparatus for low-cost fabrication of molds for microlens arrays,” J. Micromech. Microeng. 25(6), 065018 (2015).
    [Crossref]

2016 (2)

X. Zhu, L. Zhu, H. Chen, L. Yang, and W. Zhang, “Micro-ball lens structure fabrication based on drop on demand printing the liquid mold,” Appl. Surf. Sci. 361, 80–89 (2016).
[Crossref]

M. Chakrabarti, C. Dam-Hansen, J. Stubager, T. F. Pedersen, and H. C. Pedersen, “Replication of optical microlens array using photoresist coated molds,” Opt. Express 24(9), 9528–9540 (2016).
[Crossref] [PubMed]

2015 (2)

J. Pribošek and J. Diaci, “Electromagnetic microforging apparatus for low-cost fabrication of molds for microlens arrays,” J. Micromech. Microeng. 25(6), 065018 (2015).
[Crossref]

D. Xie, X. Chang, X. Shu, Y. Wang, H. Ding, and Y. Liu, “Rapid fabrication of thermoplastic polymer refractive microlens array using contactless hot embossing technology,” Opt. Express 23(4), 5154–5166 (2015).
[Crossref] [PubMed]

2014 (2)

Z. Zang, X. Tang, X. Liu, X. Lei, and W. Chen, “Fabrication of high quality and low cost microlenses on a glass substrate by direct printing technique,” Appl. Opt. 53(33), 7868–7871 (2014).
[Crossref] [PubMed]

X. Zhu, H. Chen, L. Zhu, H. Wang, and W. Zhang, “Fabrication of curved microlens array using a drop-on-demand droplet generator and polydimethylsiloxane replica mold,” Opt. Eng. 53(11), 117109 (2014).
[Crossref]

2013 (1)

2012 (2)

2010 (1)

B. McCall and T. S. Tkaczyk, “Fabrication of plastic microlens array for array microscopy by three-dimensional diamond micromilling,” Opt. Eng. 49(10), 103401 (2010).
[Crossref] [PubMed]

2007 (4)

C. R. Forest, M. A. Saez, and I. W. Hunter, “Microforging technique for rapid, low-cost fabrication of lens array molds,” Appl. Opt. 46(36), 8668–8673 (2007).
[Crossref] [PubMed]

C. Peng, X. G. Liang, Z. L. Fu, and S. Y. Chou, “High fidelity fabrication of microlens arrays by nanoimprint using conformal mold duplication and low-pressure liquid material curing,” J. Vac. Sci. Technol. 25(2), 410–414 (2007).
[Crossref]

C. Y. Chang, S. Y. Yang, and M. H. Chu, “Rapid fabrication of ultraviolet-cured polymer microlens arrays by soft roller stamping process,” Microelectron. Eng. 84(2), 355–361 (2007).
[Crossref]

M. Sokuler, D. Aronov, G. Rosenman, and L. A. Gheber, “Tailored polymer microlenses on treated glass surfaces,” Appl. Phys. Lett. 90(20), 203106 (2007).
[Crossref]

2006 (1)

L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
[Crossref]

2004 (1)

H. Yang, C. K. Chao, M. K. Wei, and C. P. Lin, “High fill-factor microlens array mold insert fabrication using a thermal reflow process,” J. Micromech. Microeng. 14(8), 1197–1204 (2004).
[Crossref]

2002 (1)

S. Moon, S. Kang, and J. U. Bu, “Fabrication of polymeric microlens of hemispherical shape using micromolding,” Opt. Eng. 41(9), 2267–2270 (2002).
[Crossref]

Allen, Y. Y.

L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
[Crossref]

Aronov, D.

M. Sokuler, D. Aronov, G. Rosenman, and L. A. Gheber, “Tailored polymer microlenses on treated glass surfaces,” Appl. Phys. Lett. 90(20), 203106 (2007).
[Crossref]

Benatar, A.

L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
[Crossref]

Bu, J. U.

S. Moon, S. Kang, and J. U. Bu, “Fabrication of polymeric microlens of hemispherical shape using micromolding,” Opt. Eng. 41(9), 2267–2270 (2002).
[Crossref]

Chakrabarti, M.

Chang, C. Y.

C. Y. Chang, S. Y. Yang, and M. H. Chu, “Rapid fabrication of ultraviolet-cured polymer microlens arrays by soft roller stamping process,” Microelectron. Eng. 84(2), 355–361 (2007).
[Crossref]

Chang, X.

Chao, C. K.

H. Yang, C. K. Chao, M. K. Wei, and C. P. Lin, “High fill-factor microlens array mold insert fabrication using a thermal reflow process,” J. Micromech. Microeng. 14(8), 1197–1204 (2004).
[Crossref]

Chen, H.

X. Zhu, L. Zhu, H. Chen, L. Yang, and W. Zhang, “Micro-ball lens structure fabrication based on drop on demand printing the liquid mold,” Appl. Surf. Sci. 361, 80–89 (2016).
[Crossref]

X. Zhu, H. Chen, L. Zhu, H. Wang, and W. Zhang, “Fabrication of curved microlens array using a drop-on-demand droplet generator and polydimethylsiloxane replica mold,” Opt. Eng. 53(11), 117109 (2014).
[Crossref]

Chen, W.

Chen, Y.

L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
[Crossref]

Chou, S. Y.

C. Peng, X. G. Liang, Z. L. Fu, and S. Y. Chou, “High fidelity fabrication of microlens arrays by nanoimprint using conformal mold duplication and low-pressure liquid material curing,” J. Vac. Sci. Technol. 25(2), 410–414 (2007).
[Crossref]

Chu, M. H.

C. Y. Chang, S. Y. Yang, and M. H. Chu, “Rapid fabrication of ultraviolet-cured polymer microlens arrays by soft roller stamping process,” Microelectron. Eng. 84(2), 355–361 (2007).
[Crossref]

Dam-Hansen, C.

Diaci, J.

J. Pribošek and J. Diaci, “Electromagnetic microforging apparatus for low-cost fabrication of molds for microlens arrays,” J. Micromech. Microeng. 25(6), 065018 (2015).
[Crossref]

Ding, H.

Forest, C. R.

Fu, Z. L.

C. Peng, X. G. Liang, Z. L. Fu, and S. Y. Chou, “High fidelity fabrication of microlens arrays by nanoimprint using conformal mold duplication and low-pressure liquid material curing,” J. Vac. Sci. Technol. 25(2), 410–414 (2007).
[Crossref]

Gheber, L. A.

M. Sokuler, D. Aronov, G. Rosenman, and L. A. Gheber, “Tailored polymer microlenses on treated glass surfaces,” Appl. Phys. Lett. 90(20), 203106 (2007).
[Crossref]

Grewell, D. A.

L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
[Crossref]

Huang, C.

L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
[Crossref]

Hunter, I. W.

Kang, S.

S. Moon, S. Kang, and J. U. Bu, “Fabrication of polymeric microlens of hemispherical shape using micromolding,” Opt. Eng. 41(9), 2267–2270 (2002).
[Crossref]

Lei, X.

Li, L.

L. Li and A. Y. Yi, “Design and fabrication of a freeform microlens array for a compact large-field-of-view compound-eye camera,” Appl. Opt. 51(12), 1843–1852 (2012).
[Crossref] [PubMed]

L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
[Crossref]

Liang, X. G.

C. Peng, X. G. Liang, Z. L. Fu, and S. Y. Chou, “High fidelity fabrication of microlens arrays by nanoimprint using conformal mold duplication and low-pressure liquid material curing,” J. Vac. Sci. Technol. 25(2), 410–414 (2007).
[Crossref]

Lin, C. P.

H. Yang, C. K. Chao, M. K. Wei, and C. P. Lin, “High fill-factor microlens array mold insert fabrication using a thermal reflow process,” J. Micromech. Microeng. 14(8), 1197–1204 (2004).
[Crossref]

Liu, X.

Liu, Y.

McCall, B.

B. McCall and T. S. Tkaczyk, “Rapid fabrication of miniature lens arrays by four-axis single point diamond machining,” Opt. Express 21(3), 3557–3572 (2013).
[Crossref] [PubMed]

B. McCall and T. S. Tkaczyk, “Fabrication of plastic microlens array for array microscopy by three-dimensional diamond micromilling,” Opt. Eng. 49(10), 103401 (2010).
[Crossref] [PubMed]

Moon, S.

S. Moon, S. Kang, and J. U. Bu, “Fabrication of polymeric microlens of hemispherical shape using micromolding,” Opt. Eng. 41(9), 2267–2270 (2002).
[Crossref]

Pedersen, H. C.

Pedersen, T. F.

Peng, C.

C. Peng, X. G. Liang, Z. L. Fu, and S. Y. Chou, “High fidelity fabrication of microlens arrays by nanoimprint using conformal mold duplication and low-pressure liquid material curing,” J. Vac. Sci. Technol. 25(2), 410–414 (2007).
[Crossref]

Pribošek, J.

J. Pribošek and J. Diaci, “Electromagnetic microforging apparatus for low-cost fabrication of molds for microlens arrays,” J. Micromech. Microeng. 25(6), 065018 (2015).
[Crossref]

Rosenman, G.

M. Sokuler, D. Aronov, G. Rosenman, and L. A. Gheber, “Tailored polymer microlenses on treated glass surfaces,” Appl. Phys. Lett. 90(20), 203106 (2007).
[Crossref]

Saez, M. A.

Shu, X.

Sokuler, M.

M. Sokuler, D. Aronov, G. Rosenman, and L. A. Gheber, “Tailored polymer microlenses on treated glass surfaces,” Appl. Phys. Lett. 90(20), 203106 (2007).
[Crossref]

Stubager, J.

Tang, X.

Tkaczyk, T. S.

B. McCall and T. S. Tkaczyk, “Rapid fabrication of miniature lens arrays by four-axis single point diamond machining,” Opt. Express 21(3), 3557–3572 (2013).
[Crossref] [PubMed]

B. McCall and T. S. Tkaczyk, “Fabrication of plastic microlens array for array microscopy by three-dimensional diamond micromilling,” Opt. Eng. 49(10), 103401 (2010).
[Crossref] [PubMed]

Wang, H.

X. Zhu, H. Chen, L. Zhu, H. Wang, and W. Zhang, “Fabrication of curved microlens array using a drop-on-demand droplet generator and polydimethylsiloxane replica mold,” Opt. Eng. 53(11), 117109 (2014).
[Crossref]

Wang, Y.

Wei, M. K.

H. Yang, C. K. Chao, M. K. Wei, and C. P. Lin, “High fill-factor microlens array mold insert fabrication using a thermal reflow process,” J. Micromech. Microeng. 14(8), 1197–1204 (2004).
[Crossref]

Xiao, J.

Xie, D.

Yang, H.

H. Yang, C. K. Chao, M. K. Wei, and C. P. Lin, “High fill-factor microlens array mold insert fabrication using a thermal reflow process,” J. Micromech. Microeng. 14(8), 1197–1204 (2004).
[Crossref]

Yang, L.

X. Zhu, L. Zhu, H. Chen, L. Yang, and W. Zhang, “Micro-ball lens structure fabrication based on drop on demand printing the liquid mold,” Appl. Surf. Sci. 361, 80–89 (2016).
[Crossref]

Yang, S. Y.

C. Y. Chang, S. Y. Yang, and M. H. Chu, “Rapid fabrication of ultraviolet-cured polymer microlens arrays by soft roller stamping process,” Microelectron. Eng. 84(2), 355–361 (2007).
[Crossref]

Yi, A. Y.

Zang, Z.

Zhang, H.

Zhang, W.

X. Zhu, L. Zhu, H. Chen, L. Yang, and W. Zhang, “Micro-ball lens structure fabrication based on drop on demand printing the liquid mold,” Appl. Surf. Sci. 361, 80–89 (2016).
[Crossref]

X. Zhu, H. Chen, L. Zhu, H. Wang, and W. Zhang, “Fabrication of curved microlens array using a drop-on-demand droplet generator and polydimethylsiloxane replica mold,” Opt. Eng. 53(11), 117109 (2014).
[Crossref]

Zhu, L.

X. Zhu, L. Zhu, H. Chen, L. Yang, and W. Zhang, “Micro-ball lens structure fabrication based on drop on demand printing the liquid mold,” Appl. Surf. Sci. 361, 80–89 (2016).
[Crossref]

X. Zhu, H. Chen, L. Zhu, H. Wang, and W. Zhang, “Fabrication of curved microlens array using a drop-on-demand droplet generator and polydimethylsiloxane replica mold,” Opt. Eng. 53(11), 117109 (2014).
[Crossref]

Zhu, X.

X. Zhu, L. Zhu, H. Chen, L. Yang, and W. Zhang, “Micro-ball lens structure fabrication based on drop on demand printing the liquid mold,” Appl. Surf. Sci. 361, 80–89 (2016).
[Crossref]

X. Zhu, H. Chen, L. Zhu, H. Wang, and W. Zhang, “Fabrication of curved microlens array using a drop-on-demand droplet generator and polydimethylsiloxane replica mold,” Opt. Eng. 53(11), 117109 (2014).
[Crossref]

Appl. Opt. (3)

Appl. Phys. Lett. (1)

M. Sokuler, D. Aronov, G. Rosenman, and L. A. Gheber, “Tailored polymer microlenses on treated glass surfaces,” Appl. Phys. Lett. 90(20), 203106 (2007).
[Crossref]

Appl. Surf. Sci. (1)

X. Zhu, L. Zhu, H. Chen, L. Yang, and W. Zhang, “Micro-ball lens structure fabrication based on drop on demand printing the liquid mold,” Appl. Surf. Sci. 361, 80–89 (2016).
[Crossref]

J. Micromech. Microeng. (2)

H. Yang, C. K. Chao, M. K. Wei, and C. P. Lin, “High fill-factor microlens array mold insert fabrication using a thermal reflow process,” J. Micromech. Microeng. 14(8), 1197–1204 (2004).
[Crossref]

J. Pribošek and J. Diaci, “Electromagnetic microforging apparatus for low-cost fabrication of molds for microlens arrays,” J. Micromech. Microeng. 25(6), 065018 (2015).
[Crossref]

J. Vac. Sci. Technol. (1)

C. Peng, X. G. Liang, Z. L. Fu, and S. Y. Chou, “High fidelity fabrication of microlens arrays by nanoimprint using conformal mold duplication and low-pressure liquid material curing,” J. Vac. Sci. Technol. 25(2), 410–414 (2007).
[Crossref]

Microelectron. Eng. (1)

C. Y. Chang, S. Y. Yang, and M. H. Chu, “Rapid fabrication of ultraviolet-cured polymer microlens arrays by soft roller stamping process,” Microelectron. Eng. 84(2), 355–361 (2007).
[Crossref]

Opt. Eng. (4)

X. Zhu, H. Chen, L. Zhu, H. Wang, and W. Zhang, “Fabrication of curved microlens array using a drop-on-demand droplet generator and polydimethylsiloxane replica mold,” Opt. Eng. 53(11), 117109 (2014).
[Crossref]

S. Moon, S. Kang, and J. U. Bu, “Fabrication of polymeric microlens of hemispherical shape using micromolding,” Opt. Eng. 41(9), 2267–2270 (2002).
[Crossref]

L. Li, Y. Y. Allen, C. Huang, D. A. Grewell, A. Benatar, and Y. Chen, “Fabrication of diffractive optics by use of slow tool servo diamond turning process,” Opt. Eng. 45(11), 113401 (2006).
[Crossref]

B. McCall and T. S. Tkaczyk, “Fabrication of plastic microlens array for array microscopy by three-dimensional diamond micromilling,” Opt. Eng. 49(10), 103401 (2010).
[Crossref] [PubMed]

Opt. Express (4)

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Figures (11)

Fig. 1
Fig. 1 Schematic of the lens array mold and the thermoplastic polymer spherical lens array fabricating process.
Fig. 2
Fig. 2 Graphic distribution of the displacement of work piece during mircoforging process, (a) pressing travel 0-0.9 mm, (b) pressing travel 0.9-1.1 mm, (c) pressing travel 1.1 mm, (d) pressing travel 1.1-1.5 mm.
Fig. 3
Fig. 3 Flow of microforging procedure.
Fig. 4
Fig. 4 Si3N4 ceramic balls.
Fig. 5
Fig. 5 Photograph of the hot-press microforging apparatus.
Fig. 6
Fig. 6 Hot-press microforging procedure.
Fig. 7
Fig. 7 Photograph of (a) the Aluminum alloy mold for spherical lens array and (b) the PMMA lens array.
Fig. 8
Fig. 8 PMMA lens array with average 3 mm diameter taken from three- dimensional optical microscope, captured from different view angles.
Fig. 9
Fig. 9 The profile of lens array measured using Taylor Hobson Form Talysurf.
Fig. 10
Fig. 10 Surface roughness measured in a 5 × 5 μm area on the fabricated lens.
Fig. 11
Fig. 11 The imaging performance of the lens array. (a) schematic illustration of the testing setup, (b) the imaging of the lens array fabricated from the aluminum alloy lens array template.

Tables (6)

Tables Icon

Table 1 Microforging technique for lens array mold and their features.

Tables Icon

Table 2 Performance of Si3N4 ceramic balls.

Tables Icon

Table 3 Technological parameters of microforging for aluminum alloy lens array mold.

Tables Icon

Table 4 Lens apertures and sag heights of 10 lenses randomly chosen from the lens array.

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Table 5 Calculation of the curvature radius, f, NA and f/# from the detected data in Table 4.

Tables Icon

Table 6 Measured surface roughness data of the fabricated lens.

Equations (4)

Equations on this page are rendered with MathJax. Learn more.

R = D 2 +4 h 2 8 h
f = R n 1
N A = D 2 f
f / # = D f

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