linear gradient filter using continuous coating method, based on multi-layer wedge-shaped film structure to achieve spatial continuous changes in the filter characteristics. The slope of the film can be adjusted according to the dispersion demand to obtain the target linear rate of change. The linear gradient filter has the ability of high integration, and has the irreplaceable advantage in the miniaturization and lightweight design of spectral instrument. Applications: Lightweight Hyper-spectral Imaging Spectrometer, portable spectrometer, medical endoscope. Standard products: Working wavelength(nm) Peak transmittance(%) Out-of-band cut-off Pass-band bandwidth Linear rate of change(nm/mm) Note 400-800nm ≥85 ≥OD3 Long Wave Pa…