An infrared narrowband filter is a filter that transmits radiation at wavelengths within a certain range while blocking the rest of the radiation outside this narrow passband. An infrared narrowband filter is defined as one that restricts the transmission of light in a narrow range of wavelengths (a passband) in the infrared while minimizing their transmission outside the passband.
It works on the principle of light wavelength, which means it only allows required infrared wavelengths to pass through while blocking the rest. This is done by coating specific optical thin films (interference films or absorption films type) on the filter substrate. These films exploit the help of properties such as reflection, light interference and absorption to choose the suitable rays of light.
Application: Gas detection（CO₂, CO, HC, NO₂, SO₂, O₃, CH₄）/Instruents and Apparatuses/Biochemical analysis/Optical instrument/Spectral measurement
Parameters and characteristics
Center wavelength(CWL): refers to the wavelength at the center of the passband of the filter, which is also the operating wavelength of the instrument or equipment.
Half Bandwidth(HPB): refers to the wavelength range width corresponding to half of the maximum transmittance in the transmission spectrum of a filter. Specifically, when a filter has the highest transmittance for a certain wavelength of light, the difference between the two wavelengths corresponding to a decrease in transmittance to half of the maximum transmittance is the half bandwidth of the filter.
Peak transmittance(Tp): The value of the highest transmittance of a bandpass filter in the passband.
Peak transmittance: The value of the highest transmittance of a bandpass filter in the passband.
The blocking range refers to the wavelength range that is required to be blocked or cut off by the filter, in addition to the passband of the filter design. Including pre deadline and long deadline. Pre blocking refers to a range where the cutoff wavelength is less than the center wavelength, while long blocking refers to a range where the cutoff wavelength is higher than the center wavelength.
The blocking depth refers to the maximum transmittance of light allowed to pass through the blocking band. It reflects the blocking effect of the filter on out of band light. To quantify this parameter, OD value (optical density) is usually used to represent it.
Substrate: SI CWL: 7720±100nm HPB: 480+80nm Tp: 85% Blocking: 200-17000nm，T<1%
| Products | INBP 7720 |
| Substrate | SI |
| CWL | 7720±100nm |
| HPB | 480+80nm |
| Tp | ≥85% |
| Blocking | 200-17000nm，T<1% |
Beijing Bodian Optical Tech. Co., Ltd.
Call us now:+86-10-67816587-8026
Email:Angelzhang@bd-optic.cn
Beijing Bodian Optical Technology Co., Ltd. 2025 All rights reserved
