INBP8900-Infrared narrow bandpass filter

Parameters and characteristics

Center wavelength(CWL):  the wavelength at the center of the passband of the filter, where the instrument or equipment operates.

Half Bandwidth(HPB): It refers to the width of the range of wavelengths corresponding to half of the maximum transmittance obtained by the transmission spectrum of a filter. That is, when the transmittance of the filter is most at a certain wavelength of light, then the respective values of the two wavelengths to subsequently the peak transmittance drop to half of the peak transmittance sum of 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.

In addition to the passband, the blocking range is the range of the wavelength that needs to be blocked or cut off by the filter, including pre-deadline and long deadlines. Long blocking is a range that has a cutoff wavelength greater than the center wavelength, and pre-blocking is a range that has a cutoff wavelength less than the center wavelength.

Blocking depth indicates the maximum amount of light that is permitted through the blocking band. The out-of-band light is blocked by a fast filtering effect. The parameter used to quantify this is OD value (optical density). This parameter is quantified using an OD value (optical density –>usually).