Patent ID: 8313254

Claim:
An image pickup apparatus comprising: a light-beam splitting mirror configured to transmit and reflect incident light that has entered the light-beam splitting mirror through a photographing optical system; an image sensor that receives light transmitted through the light-beam splitting mirror; an autofocus detecting unit that receives light reflected by the light-beam splitting mirror; a signal processing unit configured to process an image pickup signal of the image sensor; and a display unit configured to display an image being photographed, on the basis of an image signal obtained at the signal processing unit, wherein the light-beam splitting mirror has spectral characteristics including a reflectivity of 25% or more and 35% or less at all wavelengths from 400 to 650 nm and a reflectivity of 60% or more at a wavelength of 700 nm after optimization, and the light-beam splitting mirror includes only an even number of layers of a high refractive index material and the even number of layers of a low refractive index material alternately stacked on a plastic film.