Narrowband Filter

The Narrowband filter is subdivided from the band-pass filter, and its definition is the same as that of the band-pass filter, that is, this kind of filter allows optical signals to pass through in a specific wavelength band, but deviates from those outside this wavelength band. The optical signals on both sides are blocked, and the passband of the narrowband filter is relatively narrow, generally less than 5% of the central wavelength value.