Arbitrary multiple beam forming by two cascaded liquid crystal optical phased arrays

Area of Science:

• Optics and Photonics
• Non-linear Optics
• Laser Technology

Background:

• Traditional methods for laser beam splitting and steering often involve mechanical components, limiting speed and precision.
• Liquid crystal optical phased arrays (LC-OPAs) offer a promising avenue for dynamic and non-mechanical control of light.

Purpose of the Study:

• To demonstrate a new non-mechanical method for laser beam splitting and steering using cascaded LC-OPAs.
• To achieve controllable modulation of amplitude and phase for generating multiple simultaneous laser beams in arbitrary directions.

Main Methods:

• Utilized two cascaded liquid crystal optical phased arrays (LC-OPAs) with precise 4-f imaging to avoid diffraction.
• Employed the cascaded amplitude and phase (CAP) device method for numerical simulations and experimental validation.
• Investigated amplitude and phase modulation profiles and far-field intensity patterns.

Main Results:

• Successfully demonstrated near-field wavefronts for multiple simultaneous beams with arbitrary directions.
• Achieved fast multi-beam forming with high efficiency (>85% for 4 beams).
• Exhibited high accuracy with deviations less than 90μrad.

Conclusions:

• The cascaded LC-OPA method provides an effective solution for non-mechanical laser beam splitting and steering.
• The technique enables rapid generation of multiple, precisely controlled laser beams.
• This advancement holds potential for applications requiring dynamic and accurate laser beam manipulation.