Laser windows are precision plano parallel polished surfaces. Polishing the surfaces to high precision finish with very find abrasives to minimise any surface microfracture. Polishing the surfaces very slowly for greater periods of time than standard optical polishing. This is essential for laser substrates fabrication to achieve high flatness, parallelism and surface finish. The process is as detailed in custom processing page.
Mirror Substrates
Plano parallel polished laser windows uncoated with one side polished are used as mirror substrates and optical flats, coating with aluminum and gold. One surface is fine ground and the other polished from lambda 1 to lambda 10 depending on the size, application and parallism specification.
Laser Window Materials
Materials for laser windows generally include Fused Silica, borosilicate and BK7 optical glass. A Fused Silica grade for higher specification for excimer lasers developed for maximum transmission and prolonged life. For deep UV using Krf (248nm) and Arf (193nm) excimer lasers are now widely used.