290 results about "Dichroic prism" patented technology

A red light source comprising an array of LEDs 102R that emit light of a red color, a green light source comprising an array of LEDs 102G that emit light of a green color, and a blue light source comprising an array of LEDs 102B that emit light of a blue color are deployed about the periphery of a dichroic prism 101. A liquid crystal display element is illuminated by a light source device configured such that the light from the respective light sources is synthesized into white light by the dichroic prism, and projection type liquid crystal display devices and the like are configured.

The present invention provides a visible and infrared light photographing lens system. A color separating prism or the like divides an object light entering a photographing lens and then passing through a focus lens, into an object light in a visible light region and an object light in an infrared light region. A visible light image pickup element and an infrared light image pickup element are used to pick up images of the respective object lights. Further, a compensation lens can be used to adjust a position where an image of the object light in the infrared light region is formed. Consequently, visible light photographing and infrared light photographing can be simultaneously carried out by focusing on an object at the same distance.

An optical device has: a metal cooling device (500) disposed between a liquid crystal panel (441) and a light-incident side of a cross dichroic prism (443) and having a holding surface for holding polarization plates (521, 522) attached with a polarization films (521A and 522A) in a mutually spaced manner, the cooling device cooling the polarization films; a base (445) provided on the upper and lower sides of the cross dichroic prism (443) and having a cooling device attachment surface (449A) for the cooling device (500) to be attached; and a fixing member (600) provided on a light-incident side of the cross dichroic prism for locating and fixing the liquid crystal panel (441) on the light-incident side, the fixing member (600) being formed with a attachment surface (631) on which a pin (730) for mounting the liquid crystal panel (441) is formed.

A projection-type display apparatus includes a light source, a uniform illumination optical system, a color separating system for separating a white light beam emitted from the uniform illumination optical system into three color beams, three liquid crystal panels for respectively modulating each of the separated color beams, a light guide system located on an optical path of the color beam having the longest optical path among the separated color beams, a dichroic prism for synthesizing the beams modulated through the liquid crystal panels, and a projection lens for projecting the synthesized and modulated beam onto a screen. The uniform illumination optical system is provided with a uniform illumination optical device for converting the white light beam emitted from the light source into a uniform beam. Since the dichroic prism, which is an optical element that is rotationally symmetrical about the chief axis of a projection optical system, is employed as a color synthesizing system, and the uniform illumination optical device for restricting unevenness in color and luminous intensity is incorporated in the system, it is possible to realize a display apparatus which causes little unevenness in color and luminous intensity and which has a high illumination efficiency.

Disclosed is an illuminating device which, as a light source for a backlight device, mixes the colors of light rays of three prime colors radiated by light emitting diodes to emit white light. The illuminating device includes a first light source (22R) radiating light rays of the first prime color, a second light source (22G) radiating light rays of the second prime color, a third light source (22B) radiating light rays of the third prime color, optical units (23R), (23G) and (23B) which refract divergent light rays contained in the light rays of the first prime color, emitted by the first light source (22R), the light rays of the second prime color, emitted by the second light source (22G) and in the light rays of the third prime color, emitted by the third light source (22B), to form collimated light rays, and triangular prisms (24) and (25) or a dichroic prism (26) mixing the light rays of the first, second and third prime colors, emitted by these optical units, by selective transmission and reflection, based on optical properties of the light rays of the respective prime colors.

A support member (311) for supporting liquid crystal panels (441R, 441G, 441B) is disposed parallel to a cooling air flow channel formed between a light-incident end of a cross dichroic prism (45) and the respective liquid crystal panels and is constructed by a pair of components for supporting a neighborhood of the ends of the respective liquid crystal panels, so that the gap between the light-incident end of the cross dichroic prism and the respective liquid crystal panels facing the cooling air flow channel can be enlarged, thereby flowing cooling air sufficient for cooling a polarizer (446) and the respective liquid crystal panels in a direction of the cooling air flow channel for efficiently cooling them.

An aspect of the invention provides a duct capable of cooling optical modulation systems with high efficiency while realizing miniaturization and reduction of the mounted number of cooling fans. The duct can be used for a projector including plural optical modulation systems, a dichroic prism, and a projection lens, and the respective optical modulation systems include liquid crystal panels, entrance side polarization plates, viewing angle correction plates, and exit side polarization plates. The duct can have plural air guide paths through which cooling air passes, a discharge opening, entrance side discharge openings, and exit side discharge openings formed in these air guide paths. With the optical modulation systems as targets of independent cooling, the entrance side discharge openings and the exit side discharge openings with respect to the targets of independent cooling are formed in different air guide paths.

A 2-dimensional beam scan unit reflects emission beams from a red laser light source, a green laser light source and a blue laser light source and scans in a 2-dimensional direction. Diffusion plates diffuse the respective light beams scanned in the 2-dimensional direction to introduce them to corresponding spatial light modulation elements. The respective spatial light modulation elements modulate the respective lights in accordance with video signals of the respective colors. A dichroic prism multiplexes the lights of the three colors after the modulation and introduces the multiplexed lights to a projection lens so that a color image is displayed on a screen. Since the 2-dimensional light emitted from the beam scan unit is diffused to illuminate the spatial light modulation element, it is possible to change the optical axis of the beam emerging from the light diffusion member for irradiating the spatial light modulation element moment by moment, thereby effectively suppressing speckle noise.