Microchip Nd:YAG dual-frequency laser interferometer for displacement measurement.

Area of Science:

• Optics and Photonics
• Metrology
• Advanced Manufacturing

Background:

• Dual-frequency laser interferometers are crucial for high-precision measurements in manufacturing and research.
• Traditional systems often use He-Ne lasers, which have drawbacks like large size, heat radiation, and limited lifespan.
• These limitations restrict the application scope of existing interferometers.

Purpose of the Study:

• To develop and investigate a novel microchip Nd:YAG dual-frequency laser interferometer.
• To address the limitations of conventional He-Ne laser sources in interferometry.
• To demonstrate the feasibility of a compact, portable, and long-lasting laser interferometer system.

Main Methods:

• A microchip Nd:YAG laser was employed to generate a dual-frequency output with a 17.4 MHz difference via stress-induced birefringence.
• A down-conversion mixer was utilized to reduce the beat frequency to approximately 5 MHz for compatibility with phase meters.
• Experimental validation was conducted to assess the performance of the developed interferometer.

Main Results:

• The microchip Nd:YAG dual-frequency laser interferometer achieved a displacement resolution of 10 nm.
• The system demonstrated a measuring range of 500 mm.
• The microchip laser's compact size (40×40×35 mm), low power consumption, and extended lifespan were confirmed.

Conclusions:

• The microchip Nd:YAG dual-frequency laser interferometer presents a viable alternative to traditional systems.
• Its compact size, portability, and longevity offer significant advantages for various applications.
• This technology holds broad application prospects in advanced manufacturing and scientific research.