Patent ID: 8770749

Claim:
A lens comprising: a lens body; and an optical filter configured to attenuate visible light in a plurality of spectral bands, each of the plurality of spectral bands comprising an absorptance peak with a spectral bandwidth, a maximum absorptance, a center wavelength located at a midpoint of the spectral bandwidth, and an integrated absorptance peak area within the spectral bandwidth, the spectral bandwidth being equal to the full width of the absorptance peak at 80% of the maximum absorptance of the absorptance peak; wherein the optical filter comprises a blue light absorptance peak; wherein the center wavelength of the blue light absorptance peak is between about 445 nm and about 480 nm; wherein an attenuation factor of the blue light absorptance peak is greater than or equal to about 0.8 and less than 1; and wherein the attenuation factor of an absorptance peak is obtained by dividing the integrated absorptance peak area within the spectral bandwidth by the spectral bandwidth of the absorptance peak.