Realization of integrated narrow bandpass filters in the infrared region

We demonstrated a high-efficiency technique for the integration of narrow bandpass filters (NBPFs). A filter array integrated with 16 filters on a single substrate has been fabricated by twice depositing processes. The bandpass of the filters can be tuned widely and range from 2.295 to 2.967 /spl mu/m in this case. The relative full width at half maximum (FWHM) /spl delta//spl lambda///spl lambda/ of each filter is less than 0.7%. And the intensity of the bandpass is up to 41.3%.