Research On High-resolution Phase-only Liquid Spatial Light Modulator

As the basic blocks and the active components in real-time optical information processing, optical computing and optical neural network system, liquid crystal spatial light modulator has wide application in the optical correlation, optical interconnection, digital image encryption, digital holography, laser wave-front shaping. As holographic optical information technology continues to evolve, in order to improve the system's information processing ability, phase-only liquid crystal spatial light modulator resolution put forward a higher demand. The main points of this thesis are as follows:A brief introduction of the liquid crystal spatial light modulator development is given. Based on the Jones matrix theory, liquid crystal electro-optical properties and thin-film field effect transistor liquid crystal display, amplitude and phase modulation of liquid crystal spatial light modulator are analyzed.According to the drive structure and electro-optical modulation characteristics of the high-resolution LCD screen, based on the original SVGA liquid crystal spatial light modulator designed by our laboratory, retaining the SCM control module and video signal processing module, re-designing the circuit of video signal and clock signal, adjusting the register parameter settings to suit the driving conditions for high-resolution LCD screen.Phase modulation and amplitude modulation characteristics measurements are completed by the Mach-Zehnder interferometer. First, introducing the optical path and measurement method, and then by adjusting the polarizer orientation, to find the largest state of phase modulation, in this state, intensity modulation is tested to see if it met the requirements of phase-only modulation. Processing data measured, drawing out the phase and intensity modulation curves of phase-only liquid crystal spatial light modulator.Spatial light modulator is used in the digital holographic experiment as phase-shift device, then the high-resolution hologram picture recorded is reconstructed by computer and a clear picture of the object is gained. The result suggests that the high-resolution phase-only liquid spatial light modulator has wide value in optical information processing system.