Midwest Optical Systems BN450-22.5 Narrow Indigo Bandpass M22.5 Narrow Bandpass Filters BN Series Narrow Bandwidth 45-55nm FWHM* Guaranteed peak transmission ?85% Superior out-of-band blocking Designed for use with laser diodes and LEDs in applications with overwhelming ambient light StablEDGE® design reduces angular dependency and minimizes short-shifting effects Double-side polished glass for exceptional parallelism and transmitted optical wavefront Available in sizes up to 165mm sq. APPLICATIONS: BN Series are popular in factory automation applications where overwhelming ambient light (sunlight) may be present and in fluorescence applications to prevent cross-talk, while blocking excitation illumination and ambient light. NIR BN filters are commonly used in outdoor applications such as security surveillance and license plate recognition.