Patent ID: 9366808
Filing Date: 2016-06-14
CPC Classification: G01D,G01J,G01K,G01L,G02B

Claim Text:
1. An optical device comprising: an optical filter having a power transmission spectrum as a function of wavelength and a group index spectrum as a function of wavelength, the power transmission spectrum comprising a plurality of local transmission maxima and a plurality of local transmission minima, each local transmission maximum at a corresponding wavelength between two local transmission minima at wavelengths above and below the local transmission maximum; and an optical source in optical communication with the optical filter, the optical source configured to generate light having a wavelength at or in the vicinity of a wavelength at which at least one of the following quantities is at a maximum value: (a) the product of the group index spectrum and a square root of the power transmission spectrum, (b) the slope of a product of the group index spectrum and one minus the power transmission spectrum, and (c) the slope of a product of the group index spectrum and the power transmission spectrum.