Method of ghost reduction and transmission enhancement for a real image projection system

#1. Field of the Invention

#The invention pertains to the field of real image projection systems. More particularly, the invention pertains to a real image projection system having a tilted curved reflector, eliminating the need for a 50-50 beamsplitter in the system.

#2. Description of Related Art

#FIG. 1 is a side view of a preferred embodiment of the present invention, showing a tilted curved reflector, and a high transmissive beamsplitter with the background image source located overhead.

#FIG. 2 shows an alternate embodiment to that of FIG. 1, showing the tilted curved reflector with a beamsplitter coating. The background image is visible through the curved beamsplitter, thus eliminating the need for an additional tilted flat beamsplitter.

#FIG. 3 is an alternate embodiment to that of FIG. 1, comprising the tilted curved reflector and a fold mirror that diverts the input beampath at a angle near 90 degrees from the imaging axis. The curved reflector may be a beamsplitter coating to allow the use of a secondary background image.

#Definitions

#Reflector—a reflective optic, referring to a substrate having a mirror coating or partially reflective coating, such as a semi-transparent beamsplitter coated optic. This coating may be either a rear or front surface coating, depending on the surface of the substrate that is used to reflect.

#Asphere—a curve of conical baseline, such as spherical, parabolic, hyperbolic, or elliptical, and which includes an aspheric surface of revolution. Aspheric curves provide combinations of higher order terms in the curve formulas to create surfaces of revolution, such that, in combination, would produce imagery with reduced aberrations. Every optical system has inherent errors and aberrations as a function of natural physics, and slight curve deviations possible in an asphere will compensate for these phenomena.