Patent ID: 7317565

Claim:
A projection viewing system, comprising: at least a first display device displaying a first image to be viewed by a first viewer and a second display device displaying a second image to be viewed by a second viewer, at least a first protection optical system and a second protection optical system, a diffusing plate, said diffusing plate comprising a transmission type hologram, and an eyepiece optical system, said eyepiece optical system comprising a concave mirror, wherein: said first projection optical system projects an image appearing on said first display device in a first direction toward said first viewer and said second projection optical system projects an image appearing on said second display device in a direction different from said first direction toward said second viewer, said diffusing plate is located near to images projected through said first and second protection optical systems, said eyepiece optical system projects exit pupils of said first and second projection optical systems onto a viewer side, and zero-order light leaving said diffusing plate is kept from being incident on an exit pupil of said projection viewing system.