Abstract

Electrical address circuits developed for driving fast-switching ferroelectric liquid-crystal spatial light modulators (SLM) can be programmed to increase the speed of much slower responding nematic liquid-crystal SLMs. Using an addressing circuit that can switch as fast as 0.164  ms, voltages are programmed for values of phase that exceed the desired phase, and when the phase reaches the desired value, the voltage is switched to the required steady-state voltage. For a SLM that has a phase range of 3.5π and that is programmed over a 2π range, switching speed is reduced from 400  ms to between 71 and 77  ms. The speedup algorithm is applied to each pixel of the SLM together with a digital correction for a spatially nonuniform phase.

© 2006 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. Boulder Nonlinear Systems, Inc.; http://www.bnonlinear.com/products/XYphase/data/XYPhase.pdf
  2. P. J. Bos and K. R. Beran, "The pi-cell, a fast liquid-crystal optical switching device," Mol. Cryst. Liq. Cryst. 113, 329-339 (1984).
    [CrossRef]
  3. A. K. Kirby and G. D. Love, "Fast, large and controllable phase modulation using dual frequency liquid crystals," Opt. Express 12, 1470-1475 (2004).
    [CrossRef] [PubMed]
  4. S. T. Wu and C. S. Wu, "High-speed liquid-crystal modulators using transient nematic effect," J. Appl. Phys. 65, 527-532 (1989).
    [CrossRef]
  5. J. E. Stockley, Boulder Nonlinear Systems, 450 Courtney Way, No. 107, Lafayette, Colo. 80026 (personal communication, 2005).
  6. H. Melville, G. F. Milne, G. C. Spalding, W. Sibbett, K. Dholakia, and D. McGloin, "Optical trapping of three-dimensional structures using dynamic holograms," Opt. Express 11, 3562-3567 (2003).
    [CrossRef] [PubMed]
  7. D. J. Cho, S. T. Thurman, J. T. Donner, and G. M. Morris, "Characteristics of a 128 × 128 liquid-crystal spatial light modulator for wave-front generation," Opt. Lett. 23, 969-971 (1998).
    [CrossRef]
  8. X. Xun and R. W. Cohn, "Phase calibration of spatially nonuniform spatial light modulators," Appl. Opt. 43, 6400-6406 (2004).
    [CrossRef] [PubMed]
  9. S. T. Wu, "Liquid Crystals" in Handbook of Optics Vol. 2, M.Bass, E.W.Van Stryland, D.R.Williams, and W.L.Wolfe, eds. (McGraw-Hill, 1995), Chap. 14, pp. 14.12-14.17.
  10. R. W. Cohn, "Fundamental properties of spatial light modulators for the approximate optical computation of Fourier transformations: a review," Opt. Eng. 40, 2452-2463 (2001).
    [CrossRef]
  11. A video (avi format) at http://pyramid.spd.louisville.edu/∼eri/paperslowbarpres/speedup.avi shows the transient diffraction patterns with a 70 ms spiking frame without spiking (movie on left) and with spiking (movie on right). Figures 7(a) and 7(b) shows steady state images with the same field of view as the two movies in the avi file.
  12. X. Xun, X. Chang, and R. W. Cohn, "System for demonstrating arbitrary multi-spot beam steering from spatial light modulators," Opt. Express 12, 260-268 (2004).
    [CrossRef] [PubMed]

2004 (3)

2003 (1)

2001 (1)

R. W. Cohn, "Fundamental properties of spatial light modulators for the approximate optical computation of Fourier transformations: a review," Opt. Eng. 40, 2452-2463 (2001).
[CrossRef]

1998 (1)

1989 (1)

S. T. Wu and C. S. Wu, "High-speed liquid-crystal modulators using transient nematic effect," J. Appl. Phys. 65, 527-532 (1989).
[CrossRef]

1984 (1)

P. J. Bos and K. R. Beran, "The pi-cell, a fast liquid-crystal optical switching device," Mol. Cryst. Liq. Cryst. 113, 329-339 (1984).
[CrossRef]

Beran, K. R.

P. J. Bos and K. R. Beran, "The pi-cell, a fast liquid-crystal optical switching device," Mol. Cryst. Liq. Cryst. 113, 329-339 (1984).
[CrossRef]

Bos, P. J.

P. J. Bos and K. R. Beran, "The pi-cell, a fast liquid-crystal optical switching device," Mol. Cryst. Liq. Cryst. 113, 329-339 (1984).
[CrossRef]

Chang, X.

Cho, D. J.

Cohn, R. W.

Dholakia, K.

Donner, J. T.

Kirby, A. K.

Love, G. D.

McGloin, D.

Melville, H.

Milne, G. F.

Morris, G. M.

Sibbett, W.

Spalding, G. C.

Stockley, J. E.

J. E. Stockley, Boulder Nonlinear Systems, 450 Courtney Way, No. 107, Lafayette, Colo. 80026 (personal communication, 2005).

Thurman, S. T.

Wu, C. S.

S. T. Wu and C. S. Wu, "High-speed liquid-crystal modulators using transient nematic effect," J. Appl. Phys. 65, 527-532 (1989).
[CrossRef]

Wu, S. T.

S. T. Wu and C. S. Wu, "High-speed liquid-crystal modulators using transient nematic effect," J. Appl. Phys. 65, 527-532 (1989).
[CrossRef]

S. T. Wu, "Liquid Crystals" in Handbook of Optics Vol. 2, M.Bass, E.W.Van Stryland, D.R.Williams, and W.L.Wolfe, eds. (McGraw-Hill, 1995), Chap. 14, pp. 14.12-14.17.

Xun, X.

Appl. Opt. (1)

J. Appl. Phys. (1)

S. T. Wu and C. S. Wu, "High-speed liquid-crystal modulators using transient nematic effect," J. Appl. Phys. 65, 527-532 (1989).
[CrossRef]

Mol. Cryst. Liq. Cryst. (1)

P. J. Bos and K. R. Beran, "The pi-cell, a fast liquid-crystal optical switching device," Mol. Cryst. Liq. Cryst. 113, 329-339 (1984).
[CrossRef]

Opt. Eng. (1)

R. W. Cohn, "Fundamental properties of spatial light modulators for the approximate optical computation of Fourier transformations: a review," Opt. Eng. 40, 2452-2463 (2001).
[CrossRef]

Opt. Express (3)

Opt. Lett. (1)

Other (4)

A video (avi format) at http://pyramid.spd.louisville.edu/∼eri/paperslowbarpres/speedup.avi shows the transient diffraction patterns with a 70 ms spiking frame without spiking (movie on left) and with spiking (movie on right). Figures 7(a) and 7(b) shows steady state images with the same field of view as the two movies in the avi file.

Boulder Nonlinear Systems, Inc.; http://www.bnonlinear.com/products/XYphase/data/XYPhase.pdf

J. E. Stockley, Boulder Nonlinear Systems, 450 Courtney Way, No. 107, Lafayette, Colo. 80026 (personal communication, 2005).

S. T. Wu, "Liquid Crystals" in Handbook of Optics Vol. 2, M.Bass, E.W.Van Stryland, D.R.Williams, and W.L.Wolfe, eds. (McGraw-Hill, 1995), Chap. 14, pp. 14.12-14.17.

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 (10)

Fig. 1
Fig. 1

Schematic for explaining the choice of spiking voltage versus switching time ts.

Fig. 2
Fig. 2

Phase retardation of the SLM in steady state. The SLM is programmed to produce the values from the 2π operating range (thick curve) in steady state while the spiking voltage can be selected from the entire range (thick and thin curves) in order to speed up the switching of the SLM.

Fig. 3
Fig. 3

Transient responses of the SLM between pairs of grayscale levels. (a) The measured intensity transients and (b) the transient phase modulation calculated from (a) using Eq. (1). Curves on the left represent the “rising case” and curves on the right represent the “falling case.” Color is used in the online version of the paper to aid in separating the curves.

Fig. 4
Fig. 4

Measured time constants for the rising case.

Fig. 5
Fig. 5

Transient intensity of the SLM for switching between grayscale levels of (a) 20 and 56 for a 2π transition and (b) 20 and 39 for a π transition. In both (a) and (b) the solid curves show the transient intensity with the spiking frame and the dashed curves show the corresponding curves without spiking.

Fig. 6
Fig. 6

Minimum switching time to achieve a given phase shift. The rising phase starts from grayscale 20, and the spiking grayscale used is 127. The falling phase starts from grayscale 56, and the spiking grayscale used is 0.

Fig. 7
Fig. 7

Diffractive beam switching experiment. (a), (b) Diffraction patterns of spot 1 and spot 2 shown in the steady state following completion of the switching transient (Ref. 11). (c) Transient intensity of diffracted spot 2 for different durations of the intermediate spiking frame. Color is used in the online version of the paper to aid in separating the curves.

Fig. 8
Fig. 8

Comparison of (a) a slow detector and (b) a fast but noisy detector in following the transient intensity of the SLM as it is switched from grayscale level 0 to 127. Both measured responses and the resulting least-squares fit to Eq. (1) are shown.

Fig. 9
Fig. 9

Quality of the least-squares fits. (a) Intensity transients for switching between grayscale 0 and 127 (curve on left) and 127 to 0 (curve on right) together with the least-square fits. (b) The corresponding transient phase from inverting Eq. (1) for both the measurements and the fits in (a).

Fig. 10
Fig. 10

Measured fitting parameters for Eq. (3) that describe the transients for the falling case.

Tables (1)

Tables Icon

Table 1 Measured Switching Times with and without Spiking

Equations (3)

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

I ( t ) = I 0 [ 1 + cos φ ( t ) ] / 2 ,
φ ( t ) = φ 0 + ( φ 1 φ 0 ) [ 1 exp ( t t 0 Δ t ) ] ,
φ ( t ) = { φ 0 + ( φ H φ 0 ) ( t t 0 Δ t 1 ) 2 , t 0 < t t 0 + Δ t 1 , φ H + ( φ M φ H ) ( t t 0 Δ t 1 Δ t 2 ) , t 0 + Δ t 1 < t t 0 + Δ t 1 + Δ t 2 , φ M + ( φ 1 φ M ) [ 1 exp ( t t 0 Δ t 1 Δ t 2 Δ t 3 ) ] ,      t > t 0 + Δ t 1 + Δ t 2 ,

Metrics