|Code||Optical Density||Size||Center wavelength||Pass Bands||FWHM||Price||Delivery||Add to cart|
|i 246-2506-488||6.0||ø 25.4 x 6 mm||488 nm||400-471 + 504-700 nm||15 nm||495 $||4 - 5 days|
|i 246-2506-514||6.0||ø 25.4 x 6 mm||514 nm||400-496 + 532-700 nm||17 nm||495 $||4 - 5 days|
|i 246-2506-532||6.0||ø 25.4 x 6 mm||532 nm||400-517 + 548-710 nm||17 nm||495 $||4 - 5 days|
|i 246-2506-561||6.0||ø 25.4 x 6 mm||561 nm||425-542 + 580-740 nm||19 nm||495 $||4 - 5 days|
|Clear Aperture||⌀22 mm|
|Surface Quality||40 - 20 scratch & dig (MIL-PRF-13830B)|
|Surface Flatness||better than λ/2 @ 633 nm|
|Coating||S1: hard dielectric filter coating
S2: BBAR coating
|Optical Density||OD>6 at central wavelength ±2 nm|
|Transmission at Passbands||Taverage>90%|
|Laser Damage Threshold||>1 J/cm2 10 ns, 10 Hz at rejected wavelength|
Notch filters, or stop-band filters, are designed to block a specific narrow wavelength range (stop band) and to transmit broad wavelength ranges outside of this band (pass bands). These optical filters feature high optical density (OD), which is a logarithmic measurement of the percent transmission (T%):
OD = log10 1 ⁄ T%. OD is specified for the center wavelength of the stop band.
EKSMA Optics Notch filters feature OD 6.0 (transmission less than 0.0001%) that ensures effective blocking of the designated laser wavelength. The back side of the filter is anti-reflection coated at pass band regions to minimize the reflection.
The spectral characteristics of Notch filters strongly depend on the angle of incidence (AOI). We specify OD for the design wavelength at 0° AOI. As angle of incidence increases, the stop band shifts to shorter wavelengths. We provide transmission curves for different AOI values (0°, 22.5°, 45°) for each of our standard Notch filters.
Thin-film notch filters, or rejection filters, can be used for numerous applications, where some specific laser wavelengths need to be blocked, while others have to be transmitted. They are commonly used in Raman spectroscopy, medical laser systems, laser safety applications and laser-based fluorescence instruments.