Phase Modulation – Optical Principle of a FLCoS SLM
The birefringence of the liquid crystal material introduces a phase delay, allowing the FLCoS to be employed as a Spatial Light Modulator (SLM), operating as a high speed binary (0 or π ) phase modulator of coherent light from a laser. Using the QXGA-3DM, diffraction into the 1st order can be modulated up to 4.5 kHz by fully reconfigurable high resolution grating patterns.
The diffraction efficiency into the first order at room temperature is
- 10% at 544 nm
- 8% at 455 nm