US Patent 7142242 Prismatic image forming optical device adapted for miniaturization

An image forming optical device to form an image of optical light having prism shaped first and second optical devices. The first optical device has a first interface to pass the optical light into the first optical device, a first reflect interface to reflect the optical light from the first interface and a first output interface to output the optical light from the first reflect interface. The second optical device has a second interface to pass the optical light from the first output interface, a second reflect interface to reflect the optical light from the second interface and a second output interface to output the optical light from the second reflect interface. An optical axis of the optical light passing through the first interface is parallel to an optical axis of the optical light passing though the second output interface.