Characteristics of visible bandpass filters
Passband	Narrowband: passes only a few nanometers to tens of nanometers (e.g., peak 450 ± 10 nm) and is used for precision spectral analysis. Broadband: passes a wide range (e.g. 400-700nm) and is suitable for routine imaging.
Transmittance	High quality filters with peak transmittance up to 90% or more and steep edges (narrow transition bands).
Blocking	Optical densities (OD) up to OD4 (i.e., transmittance < 0.01%) in resistive band regions (e.g., UV or IR).
Substrate material	Commonly used glass BK7 (K9) or fused silica
Coating	Selective transmission is achieved by coating multilayer dielectric coatings.

What are the applications of visible bandpass filters?
Fluorescence microscopy: separation of excitation light (e.g. 488nm laser) from emission light (e.g. 520nm fluorescence), requiring narrow band filters.
Industrial inspection: contrast enhancement under LED light sources, e.g. to detect defects in printed circuit boards.
Astronomical observation: observation of the solar chromosphere using Hα filters (656.3nm).
Medical equipment: isolation of specific wavelengths in blood analyzers to avoid cross-talk.

Yutai Optics' visible bandpass filter inventory list
CWL (+/-2nm)	FWHM(+/-2nm)	T	Blocking
400	8	70-90%	OD≥4@200-1200
410	8	70-90%	OD≥4@200-1200
414	8	70-90%	OD≥4@200-1200
420	8	70-90%	OD≥4@200-1200
436	8	70-90%	OD≥4@200-1200
470	8	70-90%	OD≥4@200-1200
480	8	70-90%	OD≥4@200-1200
490	8	70-90%	OD≥4@200-1200
505	8	70-90%	OD≥4@200-1200
530	8	70-90%	OD≥4@200-1200
535	8	70-90%	OD≥4@200-1200
540	8	70-90%	OD≥4@200-1200
560	8	70-90%	OD≥4@200-1200
570	8	70-90%	OD≥4@200-1200
580	8	70-90%	OD≥4@200-1200
600	8	70-90%	OD≥4@200-1200
610	8	70-90%	OD≥4@200-1200
615	9	70-90%	OD≥4@200-1200
650	8	70-90%	OD≥4@200-1200
655	8	70-90%	OD≥4@200-1200
660	8	70-90%	OD≥4@200-1200
665	7	70-90%	OD≥4@200-1200
690	8	70-90%	OD≥4@200-1200
700	8	70-90%	OD≥4@200-1200