Microlenses are polymer or glass lenses used in a wide range of products, including mobile phone cameras, LED systems, and solar cells. These lenses require high image clarity and optical throughput.
Robust microlens quality control includes an assessment of residual stress throughout the lens. Retardation measurements to assess stress in transparent optics is measured as the phase shift between the polarized component of light along the fast axis compared to that along the slow axis. Generally, retardations are larger in areas where there is greater stress on the optic.
The Luceo LSM-9100S automated polariscope, which provides precise retardation measurements, can measure strain and stress in microlenses.