click me!

Group Velocity Delay Compensator Calcite 800/400nm, Apeture 12mm, 80-270fs

Code: 2116-002



Materials Calcite Aperture Diameter 12mm
Wavelength 800/400nm Delay Range 80-270fs between 800nm (o-ray) and 400nm (e-ray)
Coating AR@800nm+400nm Orientation Tolerance +/-0.5°
Flatness λ/4@633nm Transmission Wavefront Distortion λ/4@633nm
Surface Quality 20/10 S/D Parallelism <30 arc sec

The group velocity is different for different wavelength, it is called group velocity mismatch (GVM), and then a time delay is introduced between fundamental and second harmonic generated (SHG) wavelength, in order to compensate this time delay, an time delay compensator with orthogonal polarizations are often used. Calcite crystals and alpha-BBO crystals are most popular materials to make the time delay compensators. By rotation of compensators, the time delay could be adjusted, the listed delay range are based on a rotation range of +/-12°.   

4 weeks