Two-dimension high efficiency beam steering based on liquid crystal polarization gratings

Area of Science:

• Optics and Photonics
• Materials Science

Background:

• Cascaded liquid crystal polarization gratings (LCPGs) are used for 2D optical beam steering.
• Tilted incidence angles reduce steering efficiency due to phase modulation effects in liquid crystal half-wave plates (LC HWPs).

Purpose of the Study:

• To analyze the steering efficiency of cascaded LCPGs under tilt incidence.
• To propose and validate a compensation method to enhance steering efficiency.

Main Methods:

• Developed a simple analysis model to calculate steering efficiency for arbitrary tilt incidence.
• Derived a compensation method and formula for calculating compensation voltage for LC HWPs.
• Performed experimental validation.

Main Results:

• The analysis model accurately predicts steering efficiency under tilt incidence.
• The proposed compensation method effectively mitigates efficiency loss.
• Simulated and experimental results confirm improved steering efficiency for 2D beam scanning.

Conclusions:

• The developed compensation method enhances the steering efficiency of cascaded LCPGs under tilt incidence.
• This work provides a pathway for high-efficiency 2D beam steering using cascaded LCPGs.