Abstract: A video projector for displaying a picture based on a video signal. The video projector includes a first LCD panel for red light, a second LCD panel for green light, and a third LCD panel for blue light. A light source emits light toward the first to third LCD panels. A modulated light computer determines a correction coefficient for reducing the amount of light emitted from the light source toward the first to third LCD panels when temperature load of at least one of the first to third LCD panels increases. An emitted light amount control unit corrects the video signal with the correction coefficient and controls the amount of light emitted from the light source toward the first to third LCD panels.

Abstract: A gamma correction device for a liquid crystal display device including LCD panels. The gamma correction device includes a storage device for storing gamma correction data corresponding to chiral directions of LCD panels. A chiral direction data acquisition circuit acquires chirality data on the chiral direction of a LCD panel arranged in the liquid crystal display device. A control circuit sets a gamma correction datum adapted to the chiral directions of the LCD panel arranged in the liquid crystal display device selectively from the stored gamma correction data based on the acquired chirality data. A gamma correction circuit performs a gamma correction process on image signals provided to the LCD panel using the set gamma correction datum.

Abstract: A video projector for displaying a picture based on a video signal. The video projector includes a first LCD panel for red light, a second LCD panel for green light, and a third LCD panel for blue light. A light source emits light toward the first to third LCD panels. A modulated light computer determines a correction coefficient for reducing the amount of light emitted from the light source toward the first to third LCD panels when temperature load of at least one of the first to third LCD panels increases. An emitted light amount control unit corrects the video signal with the correction coefficient and controls the amount of light emitted from the light source toward the first to third LCD panels.

Abstract: A gamma correction device for a liquid crystal display device including LCD panels. The gamma correction device includes a storage device for storing gamma correction data corresponding to chiral directions of LCD panels. A chiral direction data acquisition circuit acquires chirality data on the chiral direction of a LCD panel arranged in the liquid crystal display device. A control circuit sets a gamma correction datum adapted to the chiral directions of the LCD panel arranged in the liquid crystal display device selectively from the stored gamma correction data based on the acquired chirality data. A gamma correction circuit performs a gamma correction process on image signals provided to the LCD panel using the set gamma correction datum.

Abstract: A video signal processing circuit inputs a video signal to perform processing such as frequency conversion as well as processing for generating data representing the APL (Average Picture Level) of a frame video for each frame period. A microcomputer functions as a dimmer arithmetic block to perform processing for generating dimmer data upon receipt of APL data, and functions as a lamp driver control block to perform processing for sending out a dimmer command to a lamp driver. The lamp driver receives the dimmer command, to control an amount of light emitted from a light source (a lamp).

Abstract: In a projection type video display apparatus comprising a light source lamp and a light valve for controlling the intensity of output light of the light source lamp, a projection type video display apparatus comprises a light source lamp cooling fan for cooling the light source lamp; judgment means for judging the brightness of an image on the basis of an image signal; first control means for controlling the luminescent intensity of the light source lamp on the basis of the results of the judgment by the judgment means; and second control means for controlling the rotational speed of the light source lamp cooling fan on the basis of the results of the judgment by the judgment means, the first control means controlling the luminescent intensity of the light source lamp such that the brighter the image is, the higher the luminescent intensity of the light source lamp becomes, and the second control means controlling the rotational speed of the light source lamp cooling fan such that the brighter the image is, t

Abstract: In a projection type video display apparatus comprising a light source lamp and a light valve for controlling the intensity of output light of the light source lamp, a projection type video display apparatus comprises a light source lamp cooling fan for cooling the light source lamp; judgment means for judging the brightness of an image on the basis of an image signal; first control means for controlling the luminescent intensity of the light source lamp on the basis of the results of the judgment by the judgment means; and second control means for controlling the rotational speed of the light source lamp cooling fan on the basis of the results of the judgment by the judgment means, the first control means controlling the luminescent intensity of the light source lamp such that the brighter the image is, the higher the luminescent intensity of the light source lamp becomes, and the second control means controlling the rotational speed of the light source lamp cooling fan such that the brighter the image is, t

Abstract: A video signal processing circuit inputs a video signal to perform processing such as frequency conversion as well as processing for generating data representing the APL (Average Picture Level) of a frame video for each frame period. A microcomputer functions as a dimmer arithmetic block to perform processing for generating dimmer data upon receipt of APL data, and functions as a lamp driver control block to perform processing for sending out a dimmer command to a lamp driver. The lamp driver receives the dimmer command, to control an amount of light emitted from a light source (a lamp).