According to the encyclopedia definition, narrowband filters are a subclass of bandpass filters and share the same definition: they allow optical signals to pass within a specific wavelength band, while blocking signals on both sides outside this band. The passband of a narrowband filter is relatively narrow, generally less than 5% of the central wavelength.
The fabrication is usually difficult, and optical thickness control is commonly adopted for process monitoring. Therefore, the preparation method becomes particularly critical when the central wavelength is short.
The 1064 nm narrowband filter produced by our company is a typical representative. 1064 nm is the operating wavelength of the Nd:YAG laser system, which is widely used in optical communications, automotive radar, Doppler wind lidar, underwater imaging, point cloud imaging radar, aerosol lidar, laser remote sensing and other fields.
Typical specifications are as follows:
Substrate: JGS1, Φ25.4 mm × 3 mm
Spectrum: Normal incidence
T > 93% @ 1064 nm
T > 93% @ 1064 ± 1 nm
FWHM: 7 nm
