ISO 9001 - AS 9100 - ITAR Standard & Custom Optical Filters and Coatings


When using a beamsplitters in an optical system, it is critical that all light incident upon the coating be reflected (R) or transmitted (T) with minimal loss due to absorption. To meet this requirement, Andover's VIS / NIR beamsplitters are constructed of all dielectric materials that keep absorption to just 0.5 - 1.0%, depending on the R/T ratio. To minimize reflections, we add broadband antireflective coatings that meet or exceed the following environmental specifications. These beamsplitters are designed for use at 45° angle of incidence in randomly polarized light.



Substrate Material:                   Schott® BK-7

Thickness:                                3mm 0.5mm

Size Tolerance:                        +0.00/-0.25mm

Coating Quality:                       60/40 per MIL-C-48497 A

Surface Quality:                       80/50 per MIL-C-48497 A

Humidity and Abrasion:           Per MIL-C-48497 A

Max. Operating Temperature:  +100°C

Flatness:                                 4 wave per 25mm or better

Parallelism:                             30 arc seconds or better

Angle of Incidence:                 45° random polarization

Min. Clear Aperature:             85% of outside dimension