655nm bandpass filter imported processed into ultra-thin optical glass with high transmittance, good finish, thickness tolerances, excellent flatness and other optical properties; coating equipment imported ion sputtering process, with labor solid film high spectral uniformity, stability and strong central performance characteristics of wave bandpass filter bandpass glass is a glass called a relatively narrow bandwidth, short-wave and long-wave significantly cut glass, as shown. Max (TM) by their spectral characteristics and the transmittance wavelength (λM) position, a short cutoff wavelength, cutoff wavelength and the half width of the long-wave represented. Bandpass maximum transmittance of the glass corresponding to half the difference between the wavelength λ1 and λ2 of (λ1-λ1) nm is called a half-width. Short-wave cut-off wavelength is in the short wavelength side of the peak, the transmittance is equal to zero wavelength. Long wave length cutoff glass in the long-wave side of the peak transmission wavelength than or equal to zero, and some species, in the long-wave side of the glass transmittance reach zero, places certain wavelength transmittance representation. Bandpass glass DTB Pinyin first letter to name, the transmittance value of the maximum wavelength position as their number. Optical indicators: center wavelength: 650nm +/- 15nm transmittance: T> 80% half-bandwidth: 50nm through the band: 600nm-620nm cutoff wavelength: 640nm-680nm cutoff rate: T <0.1% Applications: LD red laser pump Pu, red laser measuring instrument container, barcode scanners, desktop barcode scanners, laser measuring instrument, LED lights, red laser diode, IR range finder, a fingerprint identification device.