• Material: Vacuum Grade CaF₂
• Wavelength Range: 170 nm - 8.0 μm

Thorlabs CaF₂ Plano-Concave lenses are popular for many applications. For example, Plano-Concave lenses are used in a Galilean type beam expander (see Drawing tab for reference) to diverge a collimated beam to a virtual focus. Plano-Concave lenses have a negative focal length and negative spherical aberration. Negative spherical aberration can be used to balance out aberrations of other lenses in the system.

Bi-Concave Lenses are also available. Please click here for information.