- Material: Vacuum Grade CaF2
- Wavelength Range: 180nm - 8.0μm
Thorlabs CaF2 Bi-Concave lenses are popular for many applications. Bi-Concave lenses have a negative focal length and are best used to diverge a converging beam. Similar to a Plano-Concave lens, a Bi-Concave lens can diverge a collimated beam to a virtual focus as used in a Galilean type beam expander (see Drawing tab for reference).
Lens kits are available. Please click here for information.