Patent ID: 8199397

Claim:
A negative dispersion mirror comprising: a substrate; and a dielectric multilayer coating structure formed on the substrate, the dielectric multilayer coating structure including two mirror-function layer portions, each formed by a plurality of layers deposited one on another, and a cavity layer that is arranged between the two mirror-function layer portions, and which causes light having a predetermined wavelength to resonate between the two mirror-function layer portions, and wherein a dispersion value with respect to the light having the predetermined wavelength is in the range of −600 fs 2 to −3000 fs 2 and a reflectance with respect to the light having the predetermined wavelength is in the range of 97% to 99.5%, wherein each of the mirror-function layer portions is formed by layers having a relatively high refractive index and layers having a relatively low refractive index that are alternately deposited one on another, the total number of the deposited layers in each of the mirror-function layer portions is greater than or equal to eight; and wherein the number of layers of the mirror-function portion arranged in a substrate side is less than that of the mirror-function portion arranged in an incident side.