40nm bandpass filter applied to the 440nm laser, 440nm blue diode, medical instrumentation, fluorescence microscopy analysis equipment, tunable laser ink recognition Material: optical glass (in line with environmental ROHS) center wavelength of 440nm ± 2nm center wavelength transmittance> 85% peak transmittance> 85% of the half-bandwidth: 40nm ± 2nm cutoff: 200nm ~ 400nm, 500nm ~ 1100nm cutoff rate: T <0.1% Appearance requirements: 60/40