Patent ID: 7850315

Claim:
A projection apparatus, comprising: a light source module, for providing an illumination beam; a projection lens; a light valve, for converting the illumination beam into an image beam and making the image beam travel to the projection lens, wherein the illumination beam is obliquely incident upon the light valve; a light integration rod, disposed on a transmission path of the illumination beam, the light integration rod having a light input end and a light output end opposite to each other, wherein the light input end is located between the light source module and the light output end, the light output end is located between the light input end and the light valve, and the light integration rod comprises: a first reflective plate, having a short side located at the light output end and a long side; a second reflective plate, opposite to the first reflective plate and having a short side located at the light output end and a long side; a third reflective plate, connecting the first reflective plate and the second reflective plate and having a short side located at the light output end and a long side; and a fourth reflective plate, connecting the first reflective plate and the second reflective plate, the fourth reflective plate being opposite to the third reflective plate and having a short side located at the light output end and a long side, wherein a length of the long side of the first reflective plate is unequal to a length of the long side of the second reflective plate, the short side of at least one of the first reflective plate and the second reflective plate is separate from the short side of the third reflective plate and the short side of the fourth reflective plate.