Patent ID: 7953135

Claim:
A VCSEL device, comprising: a semiconductor Bragg reflector; a semiconductor active layer formed on said semiconductor Bragg reflector; a junction region provided on said active layer and configured to confine a current injected into said active layer, said junction region including a pn junction; a semiconductor layer provided on said junction region; and a dielectric Bragg reflector provided on said semiconductor layer, said dielectric Bragg reflector including a first layer directly coming in contact with said semiconductor layer and a second layer provided on said first film, wherein said first layer has a refractive index greater than a refractive index of said second layer, wherein said first layer of said dielectric Bragg reflector includes a first dielectric film and a second dielectric film, said first dielectric film directly coming in contact with said semiconductor layer, wherein said second dielectric film has a refractive index smaller than a refractive index of said first dielectric film and greater than said refractive index of said second layer, and wherein said first layer has a thickness of λ/4/n Av1 , where λ is an emission wavelength of said VCSEL device and n AV1 is an average refractive index of said first layer calculated by an equation of, n AV1 =( d 1 ×n 1 +d 2 >n 2 )/( d 1 +d 2 ), where d 1 and d 2 are thicknesses of said first and second films, respectively, and n 1 and n 2 are refractive indices of said first and second films, respectively.