Concave spherical lenses are used for light projection and beam expansion. Plano-concave (PCV) lenses have one surface with a concave radius of curvature, while the other surface is plano. This is the most common type of concave spherical lenses. With double-concave (DCV) lenses, both surfaces have a concave radius, giving them a shorter focal length than PCV lenses of equal radius of curvature.
The most common materials used for concave spherical lenses are BK7 and UVFS. However, UVFS has various grades and a specific grade of glass should be chosen for specific applications. If you have doubts about which type of glass is best for your application, contact us for advice.
Concave spherical lenses are typically coated with e-beam technology so they can reach a reflectivity of R<0.2% per surface, but for more demanding applications sputtering technology is used to achieve a reflectivity of R<0.1%.
Contact us for help with your challenge. We have a team of experienced coating engineers and metrology capabilities to prototype and transfer your idea into a well-defined production process.