CPC G02B 5/281 (2013.01) [G01N 21/35 (2013.01); G01N 29/42 (2013.01); G02B 1/115 (2013.01); G02B 5/208 (2013.01); G02B 5/288 (2013.01); G02B 13/14 (2013.01)] | 19 Claims |
1. An infrared band pass filter, comprising:
a first multilayer film, wherein the multilayer film comprises:
a plurality of Si:NH layers, wherein a refraction index of each Si:NH layer is larger than 3.5 in a wavelength range between 800 nm and 1100 nm; and
a plurality of first low refraction index layers, stacking with the plurality of Si:NH layers alternatively, wherein a refraction index of each first low refraction index layer is smaller than 3 in the wavelength range between 800 nm and 1100 nm;
a substrate, wherein the substrate is formed on the first multilayer film; and
a second multilayer film, formed on the other surface of the substrate, opposite to the first multilayer film, and wherein the second multilayer film comprises:
a plurality of Si:NH layers, wherein a refraction index of each Si:NH layer is greater than 3.5 in the wavelength range between 800 nm and 1100 nm; and
a plurality of second low refraction index layers, stacking with the plurality of Si:NH layers alternatively, wherein a refraction index of each second low refraction index layer is less than 3 in the wavelength range between 800 nm and 1100 nm;
wherein the substrate directly contacts the Si:NH layer of the first multilayer film and the Si:NH layer of the second multilayer film.
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