Patent ID: 8277049

Claim:
A projector, comprising: a red substrate, having a plurality of red light-emitting diodes (LEDs) arranged in an array and emitting red light into specific directions; a green substrate, having a plurality of green LEDs arranged in an array and emitting green light into specific directions; a blue substrate, having a plurality of blue LEDs arranged in an array and emitting blue light into specific directions; an X-cube, having a first surface, a second surface, a third surface, and a light emitting surface, wherein the red substrate, the green substrate, and the blue substrate respectively illuminate the first surface, the second surface, and the third surface, and the light from the red substrate, the green substrate, and the blue substrate is mixed in the X-cube and then exit from the light emitting surface; an electronic control element, electrically connected to the red substrate, the green substrate, and the blue substrate for controlling the same; a light guide element, for reflecting the light from the light emitting surface of the X-cube; an integrator rod, disposed between the X-cube and the light guide element, and used for uniformizing the light from the light emitting surface of the X-cube; four first prism sets, surrounding a light-incident port of the integrator rod, wherein each first prism set includes a first glass prism, a second glass prism and a cemented surface, the materials and refractive indexes of the first glass prism and the second glass prism are different, the first glass prism and the second glass prism are combined so as to form the cemented surface therebetween, the cemented surface has a special coating thereon, and the thickness of the special coating varies gradually; four second prism sets, surrounding a light-emitting port of the integrator rod, wherein each second prism set includes a third glass prism, a fourth glass prism and a cemented surface, the materials and refractive indexes of the third glass prism and the fourth glass prism are different, the third glass prism and the fourth glass prism are combined so as to form the cemented surface therebetween, the cemented surface has a special coating, and the thickness of the special coating varies gradually; a light valve element, for reflecting the light from the light guide element back to the light guide element and passing through the light guide element; and a projection lens, for projecting the light passing through the light guide element onto a projection plane area.