Wavefront control of laser beam using optically addressed liquid crystal modulator

Abstract

An optically addressed liquid crystal modulator for wavefront control of 1053 nm laser beam is reported in this paper. Its working principle, control method and spatial phase modulation capability are mainly introduced. A new method of measuring the relationship between gray level and phase retardation is proposed. The rationality of the curve is further confirmed by designing special experiments. According to the curve, several spatial phase distributions have been realized by this home-made device. The results show that, not only the maximum phase retardation is larger than $2\unicode[STIX]{x03C0}$ for 1053 nm wavelength, but also the control accuracy is high. Compared with the liquid crystal on silicon type spatial light modulator, this kind of modulator has the advantages of generating smooth phase distribution and avoiding the black-matrix effect.

Compensation method for performance degradation of optically addressed spatial light modulator induced by CW laser

“…It is reported that some liquid crystal devices have been used for more than 15 years, but the performance is still not significantly degraded. And LCSLM has been used in American NIF [7] and China's "Shenguang" [8][9][10] for beam shaping and shielding damage points. However, when the laser power reaches a high intensity, the performance of the device will degrade.…”

Investigation of the optical properties of the liquid crystal-based devices via Mueller matrix formalism

“…Liquid crystal displays (LCD) are amplitude modulators mostly used as displays in laptops, TVs, cellphones, and tablets for years [4][5][6][7]. The other kind of modulators, phase modulators, have applications such as electrically controlled lenses [8][9][10], optical tweezers [11,12], laser beam shaping [13,14], 3D holographic displays [15], and laser wavelength control [16,17].…”

Phase-Only Optically Addressable Spatial-Light Modulator and On-Line Phase-Modulation Detection System

“…An OASLM with parallel-aligned liquid-crystal light valves (LCLVs) works in phase-only mode and the influence of driving conditions on the phase-modulation capability of the OASLM is decisive for its performance. Traditional measurement of the phase retardation of a laser is performed using a Mach-Zehnder interferometer [10], Twyman-Green interferometer [11], and wave-front sensor (WFS) [12]. The first two devices are very sensitive to mechanical vibration and air turbulence, and the WFS is limited by its inherently restrictive measurement accuracy range.…”