High-precision tracking and dispersion compensation technology based on dual-liquid-crystal-polarization-grating

Area of Science:

• Optoelectronics
• Optical Engineering
• Servo Systems

Background:

• Traditional tracking systems are bulky and heavy.
• Simultaneous transmit and receive systems use different wavelengths, causing beam deviation due to grating dispersion.
• This non-coaxial issue hinders miniaturization efforts.

Purpose of the Study:

• To investigate high-precision beam tracking technology for miniaturized dual-liquid-crystal-polarizing-grating systems.
• To address beam deviation caused by grating dispersion in dual-grating systems.
• To enable coaxial beam transmission and reception for miniaturized tracking applications.

Main Methods:

• Analysis of the beam deflection control mechanism in dual-grating systems.
• Development of a comprehensive dual-grating tracking control model.
• Implementation of a dispersion angle compensation method using a fast steering mirror.

Main Results:

• Effective compensation for dispersion angles across different wavelengths.
• Successful dynamic tracking and pointing with consistent beam deflection.
• Achieved dynamic tracking accuracy of 14.33μrad, dynamic pointing accuracy of 16.27μrad, and static pointing accuracy of 4.12μrad.

Conclusions:

• The proposed method validates the feasibility of dynamic tracking and pointing for dual-grating systems.
• The technology lays the foundation for miniaturizing optoelectronic servo systems.
• High-precision beam tracking is achievable despite grating dispersion effects.