Abstract: A projection optical system includes an illumination system, a first adjusting device for adjusting an aperture size of the illumination system, a projection lens, a second adjusting device for adjusting an aperture size of the projection lens, and a controller. According to a look-up table or a predetermined calculation equation, the controller is used for controlling the second adjusting device and the first adjusting device to synchronously adjust the aperture size of the projection lens and the aperture size of the illumination system.

Abstract: A projector having a light-shielding module. The projector comprises a housing, a light engine, and a light-shielding module. The housing has a aperture. The light engine includes a projection lens. The projection lens is disposed in the housing, and relative to the aperture in order to project an image. The light-shielding module has an adjustable light-shielding zone, and is used for selectably shielding the image.

Abstract: Data coherence checking apparatus, a redundant array of independent disks (RAID) controller and a storage system having the checking apparatus and a method therefor are proposed. The present invention employs an XOR operation unit and an OR operation unit to check the coherence of data to be checked. The XOR operation unit is used to perform XOR operation on the data to be checked. After the XOR operation unit finishes performing the XOR operation on the data of a processing set, it outputs an XOR operation result to the OR operation unit to perform OR operation so as to obtain a check result.

Abstract: A light pipe is designed for a projector system. The light pipe gathers the light from a light source and guides the gathered light to an image device in the projector system. The area of the exit pupil of the light pipe is smaller than the area of the entrance pupil, and the shape of the exit pupil is scaled from that of the entrance pupil. This improves the light gathering efficiency of the light pipe.

Abstract: A light pipe is designed for a projector system. The light pipe gathers the light from a light source and guides the gathered light to an image device in the projector system. The area of the exit pupil of the light pipe is smaller than the area of the entrance pupil, and the shape of the exit pupil is scaled from that of the entrance pupil. This improves the light gathering efficiency of the light pipe.