Patent ID: 8585210

Claim:
A projection apparatus capable of projecting an image on a screen, the projection apparatus comprising: a light valve, capable of generating an image beam; and a projection lens, disposed in the transmission path of the image beam, and disposed between the light valve and the screen to project the image beam to form the image on the screen, wherein the projection lens has an optical axis, the light valve deviates an offset of X % from the optical axis in a first direction, the image deviates an offset of Y % from the optical axis in a second direction, and the first direction is opposite to the second direction, the projection lens comprising: a lens group, disposed in the transmission path of the image beam; and an asymmetric anamorphic device, disposed in the transmission path of the image beam and disposed between the lens group and the screen to make X %<Y %, wherein the asymmetric anamorphic device comprises an anamorphic transparent plate, the anamorphic transparent plate has a first end, a second end opposite the first end relative to the optical axis, a thickness of the anamorphic transparent plate continuously increases from the first end to the second end, the anamorphic transparent plate has a first light transmission area capable of allowing the image beam to pass through, the first light transmission area has a first end and a second end opposite to the first end, an angle between a first extending direction and the second direction is less than 90 degrees, a thickness of the second end in the first light transmission area is more than a thickness of the first end in the first light transmission area, and the first end of the anamorphic transparent plate is closer to the first end of the first light transmission area than is the second end of the anamorphic transparent plate along a vertical direction.