High-Range and High-Linearity 2D Angle Measurement System for a Fast Steering Mirror

Area of Science:

• Optics and Photonics
• Mechanical Engineering
• Measurement Science

Background:

• Traditional fast steering mirror (FSM) systems face limitations in angular measurement range for practical applications.
• Accurate and wide-range angle measurement is crucial in various fields, including optical systems and robotics.
• Existing FSM angle measurement techniques often struggle to balance range, linearity, and system complexity.

Purpose of the Study:

• To develop a 2D large-angle FSM photoelectric angle measurement system with an improved measurement range.
• To address the nonlinearity issues inherent in traditional angle measurement systems.
• To create a compact and robust system capable of precise angle determination over extended ranges.

Main Methods:

• A mathematical model was developed based on the physical properties of a diffuse reflecting plate, incorporating parameters like rotation angle, center, radius, and reflection coefficient.
• A method for optimizing the degree of nonlinearity was proposed and integrated into the system design.
• The system was designed, fabricated, and experimentally tested to validate its performance characteristics.

Main Results:

• The experimental results demonstrated that adjusting the diffuse reflection surface area effectively improves the nonlinearity of the angle measurement system.
• A specific configuration with a diffuse reflection surface radius of 3.3 mm achieved a measurement range of ±20° with a nonlinearity of 0.74%.
• The system achieved a high resolution of up to 2.3 arcseconds, indicating precise angle measurement capabilities.

Conclusions:

• The proposed 2D large-angle FSM photoelectric angle measurement system effectively overcomes the range limitations of traditional systems.
• Optimizing the diffuse reflection surface area is a viable strategy for enhancing linearity and overall system performance.
• The developed system offers a simple, compact, and high-performance solution for wide-range angle measurement with guaranteed linearity.