Stripe Noise Removal in Blazed Grating Generation for Electrically Tunable Beam Deflector

Area of Science:

• Optics and Photonics
• Materials Science
• Electrical Engineering

Background:

• Beam steering is crucial for applications like optical communication and imaging.
• Existing methods for beam steering often suffer from noise and limited efficiency.
• Liquid crystal devices offer tunable optical properties for dynamic beam control.

Purpose of the Study:

• To demonstrate a blazed phase grating for tunable beam steering.
• To propose a novel algorithm for reducing stripe noise in wrapped phase.
• To improve the diffraction efficiency of liquid crystal-based beam deflectors.

Main Methods:

• An electrically tunable transmission-type beam deflector using liquid crystals and patterned indium tin oxide electrodes was developed.
• Two different 2π phase-wrapping methods were applied to achieve tunable diffraction angles.
• A novel algorithm was proposed and implemented to mitigate stripe noise in the wrapped phase.

Main Results:

• The blazed phase grating enabled tunable beam steering by controlling diffraction angles.
• The method of equal interval of phase yielded higher diffraction efficiency compared to the equal interval of diffraction angle method.
• The proposed algorithm successfully eliminated stripe noise across all steering angles, enhancing overall diffraction efficiency.

Conclusions:

• The developed blazed phase grating and liquid crystal deflector provide effective tunable beam steering.
• The novel algorithm significantly reduces stripe noise, leading to improved diffraction efficiency.
• This work advances the performance of liquid crystal-based optical beam steering systems.