A design approach is described to achieve spectral blocking filters of any spectral width and optical density for narrow blocking bands. We give new criterions to find the necessary number of layers from the desired bandwidth and optical density, and give new estimate equations which describe the number of layers required for designing a blocking filter of given bandwidth, high index, and optical density. This approach can be useful for laser line blocking, night vision filters, and many other general applications.
© 2009 Chinese Optics Letters
(120.2440) Instrumentation, measurement, and metrology : Filters
(230.4170) Optical devices : Multilayers
(350.2460) Other areas of optics : Filters, interference
(310.4165) Thin films : Multilayer design
Hayder A. Ahmed, "Improved narrow wavelength band blocking filters," Chin. Opt. Lett. 7, 352-354 (2009)