CPC G02B 5/288 (2013.01) [G01J 3/28 (2013.01); G02B 5/201 (2013.01); G02B 5/28 (2013.01)] | 36 Claims |
1. An optical filter comprising:
at least one first filter element having a first center wavelength within a first wavelength band; and
at least one second filter element arranged on a same plane as the at least one first filter element, the at least one second filter element having a second center wavelength within a second wavelength band,
wherein each of the at least one first filter element comprises:
a first bandpass filter including a plurality of first Bragg reflective layers and at least one first cavity provided between the plurality of first Bragg reflective layers; and
a first multi-layer provided on the first bandpass filter, the first multi-layer having a different center wavelength than the first center wavelength of the plurality of first Bragg reflective layers to block light of other wavelength bands than the first wavelength band,
wherein the first multi-layer comprises a plurality of material layers provided above an upper most Bragg reflective layer among the plurality of first Bragg reflective layers.
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