Long / Short Wave Pass Filters (LWP / SWP)
Sharp cut filters attenuate unwanted spectral regions
- Useful as wavelength separating beamsplitters
These filters have an edge transmission coating on the front surface. A long pass filter coating reflects shorter wavelengths and transmits longer wavelengths. A short pass filter coating reflects longer wavelengths and transmits shorter wavelengths. The rear surface is coated with a broadband anti-reflection coating. The coatings are intended for use at normal incidence but these filters can be produced for use at 45° on special request.
Substrate Material: |
- BK7A
- UV
Grade Fused Silica
|
Surface Flatness: |
<2 λ / inch |
Surface Quality: |
<60 / 40 |
Wedge: |
< 3 arc min |
Cut-on (cut-off) wavelength: |
50% of peak transmittance |
Cut-on (cut-off) Accuracy: |
± 3% of wavelength |
Dimensions: |
- 25.4 mm
dia (± 0.1 mm) x 1.5 mm thick
- 50.8 mm dia
( ± 0.1 mm) x 2.0 mm thic
|
Clear Aperture: |
> 85% of dimensions |
Reflectance: |
R > 99.5% |
Transmission: |
T > 85%, below 400 nm T > 75% |
Coating: |
BBAR on second side |
Long / Short Wave Pass Filters (LWP / SWP)