Design and Optimization of Compact He-Ne Laser Interferometers for Industrial Applications

Abstract

This study presents the design and optimization aspects of a miniaturized, industrial-grade helium-neon (He-Ne) laser interferometer. Although conventional interferometers are capable of very high precision, their need for large physical size and sensitivity to environmental factors make them rarely used in the modern industrial world, where measurement devices have to be easy to transport and robust. The design was taking advantage of optical modeling by Gaussian beam theory, selective miniaturization of elements, and isolation from thermal or vibration interferences in real industrial environments. Relative to the optimum technique, the proposed arrangement optimizes cavity length, mirror reflectivity, and diverging beam dimensions to improve operating visibility. Key system parameters include the following: The prototype occupies small optical mounts, piezoelectric actuators for phase shift control, and photodetector arrays together with an on-chip real-time signal measurement algorithm. The Allen deviation and Fourier transform applied to signal analysis are powerful tools for determining how well the instrument performs. The results indicate that the improved interferometer offers sub-micron resolution, with a 45 nm offset sensitivity, a 12 nm average squared noise level under unchanging conditions, and calibration errors of ±15 nm within ±5 μm. Long-term deviation remains below 100 nm per hour. The system was tested under artificial disturbances, temperature variations from 22°C to 30°C, mechanical vibrations in the 20–100 Hz range, and changes in mounting orientation. It can be seen that the optimized compact interferometer has good accuracy of submicrons and high stability and also works out effectively in narrow spaces. The study will promote the application of such systems in advanced industrial metrology, robot calibration, and also quality control. It is the next generation of accurate manufacturing that could be a promising advancement in industrial metrology.