Patent ID: 7912364

Claim:
An optical observation apparatus comprising: penta-dach prism which reflects a first wavelength region light which has passed through a focusing screen from an object to introduce the light to an eyepiece part; and a light source which is disposed at a position optically equivalent to the focusing screen and emits a second wavelength region light that is light in a wavelength region different from that of the first wavelength region light, wherein a wavelength-selective optical film which transmits the first wavelength region light and reflects the second wavelength region light is disposed inside the penta-dach prism, and wherein the optical observation apparatus superimposes an image formed by the second wavelength region light reflected by the wavelength-selective optical film on an object image formed by the first wavelength region light transmitted through the wavelength-selective optical film to cause an observer to observe the object image with the superimposed image through the eyepiece part.