Patent ID: 8976447
Filing Date: 2015-03-10
Classification: G02B,H01S

Abstract:
1. A substantially dispersion-free optical filter cavity, comprising: a first multilayer mirror including layers of a less-refractive material and layers of a more-refractive material, the more-refractive material having a higher index of refraction than the less-refractive material, and the layers being successively arranged from an inner layer to an outer layer; a second multilayer mirror including layers of the less-refractive material and layers of the more-refractive material, and the layers being successively arranged from an inner layer to an outer layer to correspond with the arrangement of layers in the first multilayer mirror; and spacing between the first and second multilayer mirrors, wherein the first and second multilayer mirrors are configured to define an optical path for light to pass through the spacing when reflected between the mirrors, wherein the thickness of a plurality of the layers in the second multilayer mirror differ from corresponding layers in the first multilayer mirror to provide the cavity with complementary group-delay across the cavity with a phase difference within ±0.015 rad across a range of wavelengths spanning at least 50 nm, and wherein the spacing comprises a gas atmosphere at a pressure of at least about 1 kPa, and wherein the group-delay dispersion provided by the first and second multilayer mirrors balance the group-delay dispersion provided by the gas to maintain the complementary group-delay dispersion across the cavity.