A continuously variable beam expander driven by ultrasonic motors.

Area of Science:

• Optics
• Mechanical Engineering
• Materials Science

Background:

• Dynamic beam shaping systems necessitate variable beam expanders.
• Traditional expanders may lack precision or speed for certain applications.

Purpose of the Study:

• To develop and assess a novel variable beam expander for dynamic beam shaping.
• To integrate ultrasonic motors for high-precision lens positioning.

Main Methods:

• Designed a beam expander using three optical lenses.
• Incorporated two hollow ultrasonic motors with polymer-based stators for reduced weight.
• Machined a prototype and evaluated its performance characteristics.

Main Results:

• The beam expander demonstrated rapid start/stop times within 0.05 seconds.
• Achieved a minimum positioning error of 0.03 µm through motor speed adjustment.
• Successfully realized continuous threefold to fivefold laser beam expansion.

Conclusions:

• Ultrasonic motors enable nanoscale positioning for high-precision beam shaping.
• The developed variable beam expander meets the requirements for dynamic optical systems.
• The lightweight design with polymer stators enhances motor performance.