Ultraflat Thin-Film Filters
Alluxa has announced the production of ultraflat dichroic and polychroic filters with high levels of inband transmission.
The filters achieve flatness by eliminating the high stresses of an as-deposited traditional ion-based coating process. Alluxa's technique uses a plasma hard coating process that produces low-loss, fully dense dielectric films with net zero stress on the primary coated side. Because of this process, the films do not require lengthy additional coating time of backside compensation or require the use of thick and expensive substrates.