Abstract

The conventional auto-focus and zoom image systems were made by a set of motor-moved lenses. Because of mechanical moving parts, it is not easy to miniaturize their sizes. In this paper, we propose a thin autofocus system using a large stroke MEMS (micro-electro-mechanical systems) deformable mirror which has the potential to downscale the size and to minimize chromatic aberration. The large stroke MEMS deformable mirror is made by a polyimide membrane that has a maximum 12 μm displacement over a 3 mm aperture. The module size is 5.4 mm thick in optical design layout and 6.7 mm after packaging. This autofocus system is designed with the f-number = 4.13, on-axis MTF = 0.28 at full frequency of 230 cycles/mm, and incident light within ± 26 degree. The position of clear image can vary from 4 cm to 50 cm achieved by controlling the surface curvature of the MEMS deformable mirror.

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References

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  1. R. C. Gutierrez, T. K. Tang, R. Calvet, and E. R. Fossum, “MEMS digital camera,” Proc. SPIE 6502, 1-8 (2007).
  2. S. Kuiper and B. H. W. Hendriks, “Variable-focus liquid lens for miniature cameras,” Appl. Phys. Lett. 85(7), 1128–1130 (2004).
    [CrossRef]
  3. H. Ren, Y. Fan, S. Gauza, and S. Wu, “Tunable-Focus Cylindrical Liquid Crystal Lens,” Jpn. J. Appl. Phys. 43(2), 652–653 (2004).
    [CrossRef]
  4. J. L. Wang, T. Y. Chen, Y. H. Chien, and G. D. Su, “Miniature optical autofocus camera by micromachined fluoropolymer deformable mirror,” Opt. Express 17(8), 6268–6274 (2009).
    [CrossRef] [PubMed]
  5. D. Wick, “Active Optical Zoom System,” US patent 6,977,777 (2005).
  6. W. Smith, Modern Optical Engineering: the design of optical systems, 2nd, (McGraw-Hill, 1990), pp.436.
  7. E. Hecht, Optics, 4nd (Addison Wesley, 2001).
    [PubMed]
  8. Boston Micromachines Corporation, http://www.bostonmicromachines.com/ .
  9. V. T. Srikar and S. M. Spearing, “Materials selection for microfabricated electrostatic actuators,” Sens. Actuators A Phys. 102(3), 279–285 (2003).
    [CrossRef]
  10. K. Seidl, J. Knobbe, and H. Grüger, “Design of an all-reflective unobscured optical-power zoom objective,” Appl. Opt. 48(21), 4097–4107 (2009).
    [CrossRef] [PubMed]
  11. J. Wang, T. Chen, C. Liu, C. Chiu, and G. Su, “Polymer Deformable Mirror for Optical Auto Focusing,” ETRI Journal 29(6), 817–819 (2007).
    [CrossRef]

2009

2007

J. Wang, T. Chen, C. Liu, C. Chiu, and G. Su, “Polymer Deformable Mirror for Optical Auto Focusing,” ETRI Journal 29(6), 817–819 (2007).
[CrossRef]

2004

S. Kuiper and B. H. W. Hendriks, “Variable-focus liquid lens for miniature cameras,” Appl. Phys. Lett. 85(7), 1128–1130 (2004).
[CrossRef]

H. Ren, Y. Fan, S. Gauza, and S. Wu, “Tunable-Focus Cylindrical Liquid Crystal Lens,” Jpn. J. Appl. Phys. 43(2), 652–653 (2004).
[CrossRef]

2003

V. T. Srikar and S. M. Spearing, “Materials selection for microfabricated electrostatic actuators,” Sens. Actuators A Phys. 102(3), 279–285 (2003).
[CrossRef]

Chen, T.

J. Wang, T. Chen, C. Liu, C. Chiu, and G. Su, “Polymer Deformable Mirror for Optical Auto Focusing,” ETRI Journal 29(6), 817–819 (2007).
[CrossRef]

Chen, T. Y.

Chien, Y. H.

Chiu, C.

J. Wang, T. Chen, C. Liu, C. Chiu, and G. Su, “Polymer Deformable Mirror for Optical Auto Focusing,” ETRI Journal 29(6), 817–819 (2007).
[CrossRef]

Fan, Y.

H. Ren, Y. Fan, S. Gauza, and S. Wu, “Tunable-Focus Cylindrical Liquid Crystal Lens,” Jpn. J. Appl. Phys. 43(2), 652–653 (2004).
[CrossRef]

Gauza, S.

H. Ren, Y. Fan, S. Gauza, and S. Wu, “Tunable-Focus Cylindrical Liquid Crystal Lens,” Jpn. J. Appl. Phys. 43(2), 652–653 (2004).
[CrossRef]

Grüger, H.

Hendriks, B. H. W.

S. Kuiper and B. H. W. Hendriks, “Variable-focus liquid lens for miniature cameras,” Appl. Phys. Lett. 85(7), 1128–1130 (2004).
[CrossRef]

Knobbe, J.

Kuiper, S.

S. Kuiper and B. H. W. Hendriks, “Variable-focus liquid lens for miniature cameras,” Appl. Phys. Lett. 85(7), 1128–1130 (2004).
[CrossRef]

Liu, C.

J. Wang, T. Chen, C. Liu, C. Chiu, and G. Su, “Polymer Deformable Mirror for Optical Auto Focusing,” ETRI Journal 29(6), 817–819 (2007).
[CrossRef]

Ren, H.

H. Ren, Y. Fan, S. Gauza, and S. Wu, “Tunable-Focus Cylindrical Liquid Crystal Lens,” Jpn. J. Appl. Phys. 43(2), 652–653 (2004).
[CrossRef]

Seidl, K.

Spearing, S. M.

V. T. Srikar and S. M. Spearing, “Materials selection for microfabricated electrostatic actuators,” Sens. Actuators A Phys. 102(3), 279–285 (2003).
[CrossRef]

Srikar, V. T.

V. T. Srikar and S. M. Spearing, “Materials selection for microfabricated electrostatic actuators,” Sens. Actuators A Phys. 102(3), 279–285 (2003).
[CrossRef]

Su, G.

J. Wang, T. Chen, C. Liu, C. Chiu, and G. Su, “Polymer Deformable Mirror for Optical Auto Focusing,” ETRI Journal 29(6), 817–819 (2007).
[CrossRef]

Su, G. D.

Wang, J.

J. Wang, T. Chen, C. Liu, C. Chiu, and G. Su, “Polymer Deformable Mirror for Optical Auto Focusing,” ETRI Journal 29(6), 817–819 (2007).
[CrossRef]

Wang, J. L.

Wu, S.

H. Ren, Y. Fan, S. Gauza, and S. Wu, “Tunable-Focus Cylindrical Liquid Crystal Lens,” Jpn. J. Appl. Phys. 43(2), 652–653 (2004).
[CrossRef]

Appl. Opt.

Appl. Phys. Lett.

S. Kuiper and B. H. W. Hendriks, “Variable-focus liquid lens for miniature cameras,” Appl. Phys. Lett. 85(7), 1128–1130 (2004).
[CrossRef]

ETRI Journal

J. Wang, T. Chen, C. Liu, C. Chiu, and G. Su, “Polymer Deformable Mirror for Optical Auto Focusing,” ETRI Journal 29(6), 817–819 (2007).
[CrossRef]

Jpn. J. Appl. Phys.

H. Ren, Y. Fan, S. Gauza, and S. Wu, “Tunable-Focus Cylindrical Liquid Crystal Lens,” Jpn. J. Appl. Phys. 43(2), 652–653 (2004).
[CrossRef]

Opt. Express

Sens. Actuators A Phys.

V. T. Srikar and S. M. Spearing, “Materials selection for microfabricated electrostatic actuators,” Sens. Actuators A Phys. 102(3), 279–285 (2003).
[CrossRef]

Other

R. C. Gutierrez, T. K. Tang, R. Calvet, and E. R. Fossum, “MEMS digital camera,” Proc. SPIE 6502, 1-8 (2007).

D. Wick, “Active Optical Zoom System,” US patent 6,977,777 (2005).

W. Smith, Modern Optical Engineering: the design of optical systems, 2nd, (McGraw-Hill, 1990), pp.436.

E. Hecht, Optics, 4nd (Addison Wesley, 2001).
[PubMed]

Boston Micromachines Corporation, http://www.bostonmicromachines.com/ .

Supplementary Material (1)

» Media 1: MOV (1082 KB)     

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Figures (8)

Fig. 1
Fig. 1

(a) Optical system design in reflective form, and (b) its modulation transfer function (MTF) when a MEMS deformable mirror is flat for far objects

Fig. 2
Fig. 2

(a) Image simulation results of Lady Lenna, and (b) its modulation transfer function (MTF) when a MEMS deformable mirror is actuated for near objects.

Fig. 3
Fig. 3

Device fabrication processes for a top polymer membrane and a bottom electrode.

Fig. 4
Fig. 4

Schematic drawings and photos of a fabricated MEMS deformable mirror device

Fig. 5
Fig. 5

Diopter changes versus applied voltage of the polymer MEMS DM.

Fig. 6
Fig. 6

Assembly 3D drawings of an autofocus module

Fig. 7
Fig. 7

(a) Cover with a freeform mirror, (b) base with polymer MEMS DM and (c)final Assembly module

Fig. 8
Fig. 8

Pictures of near and far objects (Media 1).

Equations (1)

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P = 16 x D 2 ,

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