Abstract

This work demonstrates a reflective Fresnel zone plate based on dye-doped cholesteric liquid crystals (DDCLC) using the photo-induced realignment technique. Illumination of a DDCLC film with a laser beam through a Fresnel-zone-plate mask yields a reflective lens with binary-amplitude structures - planar and focal conic textures, which reflect and scatter probed light, respectively. The formed lens persists without any external disturbance, and its focusing efficiency, analyzed using circularly polarized light, is ~ 23.7%, which almost equals the measured diffraction efficiency of the used Fresnel-zone-plate mask (~ 25.6%). The lens is thermally erasable, rewritable and switchable between focusing and defocusing states, upon application of a voltage.

© 2007 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. L. Mingtao, J. Wang, L. Zhuang, and S. Y. Chou, "Fabrication of circular optical structures with a 20 nm minimum feature size using nanoimprint lithography," Appl. Phys. Lett. 76, 673-675 (2000).
    [CrossRef]
  2. J. Canning, K. Sommer, S. Huntington, and A. Carter, "Silica-based fiber Fresnel lens," Opt. Commun. 199, 375-381 (2001).
    [CrossRef]
  3. M. Ye and S. Sato, "Optical properties of liquid crystal lens of any size," Jpn. J. Appl. Phys. 41, L571-L573 (2002).
    [CrossRef]
  4. S. H. Chung, S. W. Choi, Y. J. Kim, H. J. Ahn and H. K. Baik, "Liquid crystal lens for compensation of spherical aberration in multilayer optical data storage," Jpn. J. Appl. Phys. 43, 1152-1157 (2006).
    [CrossRef]
  5. Y. S. Hwang, T. H. Yoon and C. Kim, "Design and fabrication of variable focusing lens array using liquid crystal for integral photography," Jpn. J. Appl. Phys. 42, 6434-6438 (2003).
    [CrossRef]
  6. H. Ren, Y.-H. Fan, and S. T. Wu, "Tunable Fresnel lens using nanoscale polymer-dispersed liquid crystals," Appl. Phys. Lett. 83, 1515-1517 (2003).
    [CrossRef]
  7. Y. H. Fan, H. Ren, and S. T. Wu, "Switchable Fresnel lens using polymer-stabilized liquid crystals," Opt. Express 11, 3080-3086 (2003).
    [CrossRef] [PubMed]
  8. D. W. Kim, C. J. Yu, H. R. Kim, S. J. Kim, and S. D. Lee, "Polarization-insensitive liquid crystal Fresnel lens of dynamic focusing in an orthogonal binary configuration," Appl. Phys. Lett. 88, 203505-203507 (2006).
    [CrossRef]
  9. T. H. Lin, Y. Huang, A. Y.-G. Fuh and S. T. Wu, "Polarization controllable Fresnel lens using dye-doped liquid crystals," Opt. Express 14, 2359-2364 (2006).
    [CrossRef] [PubMed]
  10. L. C. Lin, H. C. Jau, T. H. Lin and A. Y.-G. Fuh, "Highly efficient and polarization-independent Fresnel lens based on dye-doped liquid crystal," Opt. Express 15, 2900-2906 (2007).
    [CrossRef] [PubMed]
  11. C. R. Lee, T. L. Fu, K. T. Cheng, T. S. Mo and A. Y.-G. Fuh, "Surface-assisted photo-alignment in dye-doped liquid crystal films," Phys. Rev. E 69, 031704 (2004).
    [CrossRef]
  12. K. Rastani, A. Marrakchi, S. F. Habiby, W. M. Hubbard, H. Gilchrist and R. E. Nahory, "Binary phase Fresnel lenses for generation of two-dimensional beam arrays," Appl. Opt. 30, 1347-1354 (1991).
    [CrossRef] [PubMed]
  13. P. G. de Gennes and J. Prost, The Physics of Liquid Crystal (Oxford University Press, New York, 1993), Chap. 6.
  14. Q. Hong, T. X. Wu and S. T. Wu, "Optical wave propagation in a cholesteric liquid crystal using the finite element method," Liq. Cryst. 30, 367-375 (2003).
    [CrossRef]
  15. F. Simoni and O. Francescangeli, "Effects of light on molecular orientation of liquid crystals," J. Phys. Condens. Matter 11, R439-R487 (1999).
    [CrossRef]
  16. G. H. Heilmeier and L. A. Zanoni, "Guest-Host interactions in nematic liquid crystals: A new electro-optic effect," Appl. Phys. Lett. 13, 91-92 (1968).
    [CrossRef]
  17. A. Y.-G. Fuh, K. T. Cheng and C. R. Lee, "Biphotonic recording effect of polarization gratings based on dye-doped liquid crystal films," Liq. Cryst. 34, 389-393 (2007).
    [CrossRef]

2007 (2)

A. Y.-G. Fuh, K. T. Cheng and C. R. Lee, "Biphotonic recording effect of polarization gratings based on dye-doped liquid crystal films," Liq. Cryst. 34, 389-393 (2007).
[CrossRef]

L. C. Lin, H. C. Jau, T. H. Lin and A. Y.-G. Fuh, "Highly efficient and polarization-independent Fresnel lens based on dye-doped liquid crystal," Opt. Express 15, 2900-2906 (2007).
[CrossRef] [PubMed]

2006 (3)

T. H. Lin, Y. Huang, A. Y.-G. Fuh and S. T. Wu, "Polarization controllable Fresnel lens using dye-doped liquid crystals," Opt. Express 14, 2359-2364 (2006).
[CrossRef] [PubMed]

S. H. Chung, S. W. Choi, Y. J. Kim, H. J. Ahn and H. K. Baik, "Liquid crystal lens for compensation of spherical aberration in multilayer optical data storage," Jpn. J. Appl. Phys. 43, 1152-1157 (2006).
[CrossRef]

D. W. Kim, C. J. Yu, H. R. Kim, S. J. Kim, and S. D. Lee, "Polarization-insensitive liquid crystal Fresnel lens of dynamic focusing in an orthogonal binary configuration," Appl. Phys. Lett. 88, 203505-203507 (2006).
[CrossRef]

2004 (1)

C. R. Lee, T. L. Fu, K. T. Cheng, T. S. Mo and A. Y.-G. Fuh, "Surface-assisted photo-alignment in dye-doped liquid crystal films," Phys. Rev. E 69, 031704 (2004).
[CrossRef]

2003 (4)

Q. Hong, T. X. Wu and S. T. Wu, "Optical wave propagation in a cholesteric liquid crystal using the finite element method," Liq. Cryst. 30, 367-375 (2003).
[CrossRef]

Y. S. Hwang, T. H. Yoon and C. Kim, "Design and fabrication of variable focusing lens array using liquid crystal for integral photography," Jpn. J. Appl. Phys. 42, 6434-6438 (2003).
[CrossRef]

H. Ren, Y.-H. Fan, and S. T. Wu, "Tunable Fresnel lens using nanoscale polymer-dispersed liquid crystals," Appl. Phys. Lett. 83, 1515-1517 (2003).
[CrossRef]

Y. H. Fan, H. Ren, and S. T. Wu, "Switchable Fresnel lens using polymer-stabilized liquid crystals," Opt. Express 11, 3080-3086 (2003).
[CrossRef] [PubMed]

2002 (1)

M. Ye and S. Sato, "Optical properties of liquid crystal lens of any size," Jpn. J. Appl. Phys. 41, L571-L573 (2002).
[CrossRef]

2001 (1)

J. Canning, K. Sommer, S. Huntington, and A. Carter, "Silica-based fiber Fresnel lens," Opt. Commun. 199, 375-381 (2001).
[CrossRef]

2000 (1)

L. Mingtao, J. Wang, L. Zhuang, and S. Y. Chou, "Fabrication of circular optical structures with a 20 nm minimum feature size using nanoimprint lithography," Appl. Phys. Lett. 76, 673-675 (2000).
[CrossRef]

1999 (1)

F. Simoni and O. Francescangeli, "Effects of light on molecular orientation of liquid crystals," J. Phys. Condens. Matter 11, R439-R487 (1999).
[CrossRef]

1991 (1)

1968 (1)

G. H. Heilmeier and L. A. Zanoni, "Guest-Host interactions in nematic liquid crystals: A new electro-optic effect," Appl. Phys. Lett. 13, 91-92 (1968).
[CrossRef]

Ahn, H. J.

S. H. Chung, S. W. Choi, Y. J. Kim, H. J. Ahn and H. K. Baik, "Liquid crystal lens for compensation of spherical aberration in multilayer optical data storage," Jpn. J. Appl. Phys. 43, 1152-1157 (2006).
[CrossRef]

Baik, H. K.

S. H. Chung, S. W. Choi, Y. J. Kim, H. J. Ahn and H. K. Baik, "Liquid crystal lens for compensation of spherical aberration in multilayer optical data storage," Jpn. J. Appl. Phys. 43, 1152-1157 (2006).
[CrossRef]

Canning, J.

J. Canning, K. Sommer, S. Huntington, and A. Carter, "Silica-based fiber Fresnel lens," Opt. Commun. 199, 375-381 (2001).
[CrossRef]

Carter, A.

J. Canning, K. Sommer, S. Huntington, and A. Carter, "Silica-based fiber Fresnel lens," Opt. Commun. 199, 375-381 (2001).
[CrossRef]

Cheng, K. T.

A. Y.-G. Fuh, K. T. Cheng and C. R. Lee, "Biphotonic recording effect of polarization gratings based on dye-doped liquid crystal films," Liq. Cryst. 34, 389-393 (2007).
[CrossRef]

C. R. Lee, T. L. Fu, K. T. Cheng, T. S. Mo and A. Y.-G. Fuh, "Surface-assisted photo-alignment in dye-doped liquid crystal films," Phys. Rev. E 69, 031704 (2004).
[CrossRef]

Choi, S. W.

S. H. Chung, S. W. Choi, Y. J. Kim, H. J. Ahn and H. K. Baik, "Liquid crystal lens for compensation of spherical aberration in multilayer optical data storage," Jpn. J. Appl. Phys. 43, 1152-1157 (2006).
[CrossRef]

Chou, S. Y.

L. Mingtao, J. Wang, L. Zhuang, and S. Y. Chou, "Fabrication of circular optical structures with a 20 nm minimum feature size using nanoimprint lithography," Appl. Phys. Lett. 76, 673-675 (2000).
[CrossRef]

Chung, S. H.

S. H. Chung, S. W. Choi, Y. J. Kim, H. J. Ahn and H. K. Baik, "Liquid crystal lens for compensation of spherical aberration in multilayer optical data storage," Jpn. J. Appl. Phys. 43, 1152-1157 (2006).
[CrossRef]

Fan, Y. H.

Fan, Y.-H.

H. Ren, Y.-H. Fan, and S. T. Wu, "Tunable Fresnel lens using nanoscale polymer-dispersed liquid crystals," Appl. Phys. Lett. 83, 1515-1517 (2003).
[CrossRef]

Francescangeli, O.

F. Simoni and O. Francescangeli, "Effects of light on molecular orientation of liquid crystals," J. Phys. Condens. Matter 11, R439-R487 (1999).
[CrossRef]

Fu, T. L.

C. R. Lee, T. L. Fu, K. T. Cheng, T. S. Mo and A. Y.-G. Fuh, "Surface-assisted photo-alignment in dye-doped liquid crystal films," Phys. Rev. E 69, 031704 (2004).
[CrossRef]

Fuh, A. Y.-G.

L. C. Lin, H. C. Jau, T. H. Lin and A. Y.-G. Fuh, "Highly efficient and polarization-independent Fresnel lens based on dye-doped liquid crystal," Opt. Express 15, 2900-2906 (2007).
[CrossRef] [PubMed]

A. Y.-G. Fuh, K. T. Cheng and C. R. Lee, "Biphotonic recording effect of polarization gratings based on dye-doped liquid crystal films," Liq. Cryst. 34, 389-393 (2007).
[CrossRef]

T. H. Lin, Y. Huang, A. Y.-G. Fuh and S. T. Wu, "Polarization controllable Fresnel lens using dye-doped liquid crystals," Opt. Express 14, 2359-2364 (2006).
[CrossRef] [PubMed]

C. R. Lee, T. L. Fu, K. T. Cheng, T. S. Mo and A. Y.-G. Fuh, "Surface-assisted photo-alignment in dye-doped liquid crystal films," Phys. Rev. E 69, 031704 (2004).
[CrossRef]

Gilchrist, H.

Habiby, S. F.

Heilmeier, G. H.

G. H. Heilmeier and L. A. Zanoni, "Guest-Host interactions in nematic liquid crystals: A new electro-optic effect," Appl. Phys. Lett. 13, 91-92 (1968).
[CrossRef]

Hong, Q.

Q. Hong, T. X. Wu and S. T. Wu, "Optical wave propagation in a cholesteric liquid crystal using the finite element method," Liq. Cryst. 30, 367-375 (2003).
[CrossRef]

Huang, Y.

Hubbard, W. M.

Huntington, S.

J. Canning, K. Sommer, S. Huntington, and A. Carter, "Silica-based fiber Fresnel lens," Opt. Commun. 199, 375-381 (2001).
[CrossRef]

Hwang, Y. S.

Y. S. Hwang, T. H. Yoon and C. Kim, "Design and fabrication of variable focusing lens array using liquid crystal for integral photography," Jpn. J. Appl. Phys. 42, 6434-6438 (2003).
[CrossRef]

Jau, H. C.

Kim, C.

Y. S. Hwang, T. H. Yoon and C. Kim, "Design and fabrication of variable focusing lens array using liquid crystal for integral photography," Jpn. J. Appl. Phys. 42, 6434-6438 (2003).
[CrossRef]

Kim, D. W.

D. W. Kim, C. J. Yu, H. R. Kim, S. J. Kim, and S. D. Lee, "Polarization-insensitive liquid crystal Fresnel lens of dynamic focusing in an orthogonal binary configuration," Appl. Phys. Lett. 88, 203505-203507 (2006).
[CrossRef]

Kim, H. R.

D. W. Kim, C. J. Yu, H. R. Kim, S. J. Kim, and S. D. Lee, "Polarization-insensitive liquid crystal Fresnel lens of dynamic focusing in an orthogonal binary configuration," Appl. Phys. Lett. 88, 203505-203507 (2006).
[CrossRef]

Kim, S. J.

D. W. Kim, C. J. Yu, H. R. Kim, S. J. Kim, and S. D. Lee, "Polarization-insensitive liquid crystal Fresnel lens of dynamic focusing in an orthogonal binary configuration," Appl. Phys. Lett. 88, 203505-203507 (2006).
[CrossRef]

Kim, Y. J.

S. H. Chung, S. W. Choi, Y. J. Kim, H. J. Ahn and H. K. Baik, "Liquid crystal lens for compensation of spherical aberration in multilayer optical data storage," Jpn. J. Appl. Phys. 43, 1152-1157 (2006).
[CrossRef]

Lee, C. R.

A. Y.-G. Fuh, K. T. Cheng and C. R. Lee, "Biphotonic recording effect of polarization gratings based on dye-doped liquid crystal films," Liq. Cryst. 34, 389-393 (2007).
[CrossRef]

C. R. Lee, T. L. Fu, K. T. Cheng, T. S. Mo and A. Y.-G. Fuh, "Surface-assisted photo-alignment in dye-doped liquid crystal films," Phys. Rev. E 69, 031704 (2004).
[CrossRef]

Lee, S. D.

D. W. Kim, C. J. Yu, H. R. Kim, S. J. Kim, and S. D. Lee, "Polarization-insensitive liquid crystal Fresnel lens of dynamic focusing in an orthogonal binary configuration," Appl. Phys. Lett. 88, 203505-203507 (2006).
[CrossRef]

Lin, L. C.

Lin, T. H.

Marrakchi, A.

Mingtao, L.

L. Mingtao, J. Wang, L. Zhuang, and S. Y. Chou, "Fabrication of circular optical structures with a 20 nm minimum feature size using nanoimprint lithography," Appl. Phys. Lett. 76, 673-675 (2000).
[CrossRef]

Mo, T. S.

C. R. Lee, T. L. Fu, K. T. Cheng, T. S. Mo and A. Y.-G. Fuh, "Surface-assisted photo-alignment in dye-doped liquid crystal films," Phys. Rev. E 69, 031704 (2004).
[CrossRef]

Nahory, R. E.

Rastani, K.

Ren, H.

Y. H. Fan, H. Ren, and S. T. Wu, "Switchable Fresnel lens using polymer-stabilized liquid crystals," Opt. Express 11, 3080-3086 (2003).
[CrossRef] [PubMed]

H. Ren, Y.-H. Fan, and S. T. Wu, "Tunable Fresnel lens using nanoscale polymer-dispersed liquid crystals," Appl. Phys. Lett. 83, 1515-1517 (2003).
[CrossRef]

Sato, S.

M. Ye and S. Sato, "Optical properties of liquid crystal lens of any size," Jpn. J. Appl. Phys. 41, L571-L573 (2002).
[CrossRef]

Simoni, F.

F. Simoni and O. Francescangeli, "Effects of light on molecular orientation of liquid crystals," J. Phys. Condens. Matter 11, R439-R487 (1999).
[CrossRef]

Sommer, K.

J. Canning, K. Sommer, S. Huntington, and A. Carter, "Silica-based fiber Fresnel lens," Opt. Commun. 199, 375-381 (2001).
[CrossRef]

Wang, J.

L. Mingtao, J. Wang, L. Zhuang, and S. Y. Chou, "Fabrication of circular optical structures with a 20 nm minimum feature size using nanoimprint lithography," Appl. Phys. Lett. 76, 673-675 (2000).
[CrossRef]

Wu, S. T.

T. H. Lin, Y. Huang, A. Y.-G. Fuh and S. T. Wu, "Polarization controllable Fresnel lens using dye-doped liquid crystals," Opt. Express 14, 2359-2364 (2006).
[CrossRef] [PubMed]

Y. H. Fan, H. Ren, and S. T. Wu, "Switchable Fresnel lens using polymer-stabilized liquid crystals," Opt. Express 11, 3080-3086 (2003).
[CrossRef] [PubMed]

H. Ren, Y.-H. Fan, and S. T. Wu, "Tunable Fresnel lens using nanoscale polymer-dispersed liquid crystals," Appl. Phys. Lett. 83, 1515-1517 (2003).
[CrossRef]

Q. Hong, T. X. Wu and S. T. Wu, "Optical wave propagation in a cholesteric liquid crystal using the finite element method," Liq. Cryst. 30, 367-375 (2003).
[CrossRef]

Wu, T. X.

Q. Hong, T. X. Wu and S. T. Wu, "Optical wave propagation in a cholesteric liquid crystal using the finite element method," Liq. Cryst. 30, 367-375 (2003).
[CrossRef]

Ye, M.

M. Ye and S. Sato, "Optical properties of liquid crystal lens of any size," Jpn. J. Appl. Phys. 41, L571-L573 (2002).
[CrossRef]

Yoon, T. H.

Y. S. Hwang, T. H. Yoon and C. Kim, "Design and fabrication of variable focusing lens array using liquid crystal for integral photography," Jpn. J. Appl. Phys. 42, 6434-6438 (2003).
[CrossRef]

Yu, C. J.

D. W. Kim, C. J. Yu, H. R. Kim, S. J. Kim, and S. D. Lee, "Polarization-insensitive liquid crystal Fresnel lens of dynamic focusing in an orthogonal binary configuration," Appl. Phys. Lett. 88, 203505-203507 (2006).
[CrossRef]

Zanoni, L. A.

G. H. Heilmeier and L. A. Zanoni, "Guest-Host interactions in nematic liquid crystals: A new electro-optic effect," Appl. Phys. Lett. 13, 91-92 (1968).
[CrossRef]

Zhuang, L.

L. Mingtao, J. Wang, L. Zhuang, and S. Y. Chou, "Fabrication of circular optical structures with a 20 nm minimum feature size using nanoimprint lithography," Appl. Phys. Lett. 76, 673-675 (2000).
[CrossRef]

Appl. Opt. (1)

Appl. Phys. Lett. (4)

G. H. Heilmeier and L. A. Zanoni, "Guest-Host interactions in nematic liquid crystals: A new electro-optic effect," Appl. Phys. Lett. 13, 91-92 (1968).
[CrossRef]

L. Mingtao, J. Wang, L. Zhuang, and S. Y. Chou, "Fabrication of circular optical structures with a 20 nm minimum feature size using nanoimprint lithography," Appl. Phys. Lett. 76, 673-675 (2000).
[CrossRef]

H. Ren, Y.-H. Fan, and S. T. Wu, "Tunable Fresnel lens using nanoscale polymer-dispersed liquid crystals," Appl. Phys. Lett. 83, 1515-1517 (2003).
[CrossRef]

D. W. Kim, C. J. Yu, H. R. Kim, S. J. Kim, and S. D. Lee, "Polarization-insensitive liquid crystal Fresnel lens of dynamic focusing in an orthogonal binary configuration," Appl. Phys. Lett. 88, 203505-203507 (2006).
[CrossRef]

J. Phys. Condens. Matter (1)

F. Simoni and O. Francescangeli, "Effects of light on molecular orientation of liquid crystals," J. Phys. Condens. Matter 11, R439-R487 (1999).
[CrossRef]

Jpn. J. Appl. Phys. (3)

M. Ye and S. Sato, "Optical properties of liquid crystal lens of any size," Jpn. J. Appl. Phys. 41, L571-L573 (2002).
[CrossRef]

S. H. Chung, S. W. Choi, Y. J. Kim, H. J. Ahn and H. K. Baik, "Liquid crystal lens for compensation of spherical aberration in multilayer optical data storage," Jpn. J. Appl. Phys. 43, 1152-1157 (2006).
[CrossRef]

Y. S. Hwang, T. H. Yoon and C. Kim, "Design and fabrication of variable focusing lens array using liquid crystal for integral photography," Jpn. J. Appl. Phys. 42, 6434-6438 (2003).
[CrossRef]

Liq. Cryst. (2)

Q. Hong, T. X. Wu and S. T. Wu, "Optical wave propagation in a cholesteric liquid crystal using the finite element method," Liq. Cryst. 30, 367-375 (2003).
[CrossRef]

A. Y.-G. Fuh, K. T. Cheng and C. R. Lee, "Biphotonic recording effect of polarization gratings based on dye-doped liquid crystal films," Liq. Cryst. 34, 389-393 (2007).
[CrossRef]

Opt. Commun. (1)

J. Canning, K. Sommer, S. Huntington, and A. Carter, "Silica-based fiber Fresnel lens," Opt. Commun. 199, 375-381 (2001).
[CrossRef]

Opt. Express (3)

Phys. Rev. E (1)

C. R. Lee, T. L. Fu, K. T. Cheng, T. S. Mo and A. Y.-G. Fuh, "Surface-assisted photo-alignment in dye-doped liquid crystal films," Phys. Rev. E 69, 031704 (2004).
[CrossRef]

Other (1)

P. G. de Gennes and J. Prost, The Physics of Liquid Crystal (Oxford University Press, New York, 1993), Chap. 6.

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 (7)

Fig. 1.
Fig. 1.

Schematic fabrication of a DDCLC reflective Fresnel zone plate.

Fig. 2.
Fig. 2.

Experimental setup for (a) recording, and (b) analyzing a DDCLC reflective Fresnel zone plate.

Fig. 3.
Fig. 3.

Images of (a) Fresnel-zone-plate mask (b) formed reflective Fresnel zone plate observed under crossed-polarizer optical microscope. AT and AO represent transparent and opaque regions. AP and AF are the planar and focal conic texture regions, respectively. P and A are, respectively, the transmissive axes of the polarizer and the analyzer.

Fig. 4.
Fig. 4.

Focusing patterns of the fabricated reflective Fresnel zone plate using right-hand circularly polarized red light. The distances between lens and screen are (a) 20 cm; (b) 30 cm; (c) 40 cm; (d) 50 cm; (e) 60 cm. The Fresnel-zone-plate mask has a focal length ~ 40 cm at a wavelength of 632.8 nm..

Fig. 5.
Fig. 5.

Measured focusing efficiency of reflective Fresnel zone plate in DDCLC as a function of applied AC (1 kHz) voltage. Inset (a) and (b) present focusing patterns of lens without and with applied voltage (10 V), respectively. Notably, the focusing pattern of the lens returns to (a) after a higher voltage of 50 V is applied and rapidly switched off.

Fig. 6.
Fig. 6.

Images of reflective Fresnel zone plate observed under a crossed-polarizer optical microscope (a) before, and (b) after thermal treatment. (c) Image of rewritten reflective Fresnel zone plate. Additionally, P and A are transmissive axes of polarizer and analyzer, respectively.

Fig. 7.
Fig. 7.

(a). Reflective and (b) transmissive focusing patterns of the fabricated Fresnel zone plate using a linearly polarized red light.

Metrics