Research Progress of Stress Measurement Technologies for Optical Elements

Table 1

Comparison between different methods.

Method	Key equipment	Advantage	Disadvantage	Stress precision
DP	Polarization camera, image sensor	Automatic, high resolution	Complexity, Inflexibility	184 kPa (4 nm/cm)
PEM	Photoelastic modulator	High sensitivity, high speed, good stability	Limited measurement range	0.2 kPa (0.008 nm/cm)
LDV	Laser Doppler vibrometer	High sensitivity, good visualization, good stability	Inability to detect the shear wave directly	0.036 Pa
LSI	Laser self-mixing interferometer	Simple, low cost, wide range	Limited measurement accuracy	0.152 nm/cm
LFI	Laser feedback interferometer	Simple, low cost	Limited measurement accuracy	19 nm/cm
CRD	Light source, optical resonator	High sensitivity, wide range	Low engineering applicability	0.03 kPa (12 × 10^−4 nm/cm)