Optical Stress Viewer
The SV60 stress viewer is a medium aperture test device for checking stress in visually transparent optical components, especially those made using ZnSe. Stress from physical damage, incorrect mounting and high intensity radiation can cause non-reversible stress in the lens material. Stress shows up as birefringence, which can be seen when the component is viewed between two crossed polarizers and illuminated with visible light. Stress birefringence reduces the performance of an optic.
Lenses that are stressed by the mount may spring back when removed from the mount. In this situation small permanent stress crosses will be visible around the lens edge indicating that the lens was under severe stress when mounted.
The SV60 illuminates the test lens from below and is viewed through a magnifying lens which provides greater details of the stress. An opal screen below the lower polarizer provides uniform lighting. The SV60 is supplied with a 1.5 and a 2.0 lens holder. Mounted lenses can also be viewed.
||245 mm x 100 mm x 120 mm (HxWxD)
||Aluminum alloy, black anodized
||60 mm diameter
||240 V or 110 V, must be specified upon ordering
||Lower is fixed
||Opal screen below lower polarizer