Abstract: A prism unit includes a prism having at least one optical surface in its inside, and a prism base disposing the prism, the prism base including at least three seating surfaces that are attached to a surface orthogonal to the optical surface of the prism, a seating surface bonded part that is bonded to the prism by an adhesive. At least the three seating surfaces and the seating surface bonded part are symmetrically arranged on the optical surface of the prism.

Abstract: An LED display apparatus 1 in which at least multiple LEDs are serially-connected to a power circuit part having a constant current power source, each one of the LEDs has a switching element parallel-connected thereto, and a control circuit part is used to selectively turn on/off the switching elements to control the LEDs for a specific display, characterized by the fact that the apparatus comprises a display matrix circuit part 9 constituted by parallel-connecting to the power circuit part 8 multiple LED circuits 7a, 7b, 7c . . . consisting of multiple LEDs 2 . . . and a single first switching element 3a, 3b, 3c . . . serially-connected and second switching element 4 . . . each parallel-connected to one of the LEDs 2 . . . , and a control circuit part 10 turning on the first switching elements 3a . . . for a given time period (Ts) in sequence and turning on/off a row La, Lb, Lc . . . of multiple second switching elements 4 . . . extending across the LED circuits 7a . . .

Abstract: The present invention relates to a color separating-combining optical system of a configuration having a separating optical system which separates light from a light source into a plurality of color spectrums; a combining optical system which combines light spectrums from a plurality of image display elements illuminated by the respective color spectrums; a filter which transmits a color spectrum of a specific wavelength band out of the plurality of color spectrums separated by the separating optical system; and a plurality of polarizing elements each disposed on the light entrance side of the plurality of image display elements, the polarizing elements being adapted to analyze the corresponding color spectrums incident to the respective image display elements. The color separating-combining optical system is further characterized in that the filter is placed apart from the polarizing element corresponding to the color spectrum transmitted by the filter.

Abstract: An optical modulation element unit is disclosed which employs a film-type optical function member and a reflective optical modulation element and allows dust prevention for the reflective optical modulation element while preventing an increased number of parts other than optically required parts. The optical modulation element unit includes a light-transmissive substrate, a film-type optical function member attached to the light-transmissive substrate, a reflective optical modulation element separately placed from the light-transmissive substrate, a cover member which surrounds a space between the light-transmissive substrate and the reflective optical modulation element, and a holding member which holds the light-transmissive substrate. The holding member has a guide portion which guides an air flow to a space along a surface of the light-transmissive substrate, the surface being a surface on the side opposite to the reflective optical modulation element.

Abstract: The present invention relates to a color separating-combining optical system of a configuration having a separating optical system which separates light from a light source into a plurality of color spectrums; a combining optical system which combines light spectrums from a plurality of image display elements illuminated by the respective color spectrums; a filter which transmits a color spectrum of a specific wavelength band out of the plurality of color spectrums separated by the separating optical system; and a plurality of polarizing elements each disposed on the light entrance side of the plurality of image display elements, the polarizing elements being adapted to analyze the corresponding color spectrums incident to the respective image display elements. The color separating-combining optical system is further characterized in that the filter is placed apart from the polarizing element corresponding to the color spectrum transmitted by the filter.

Abstract: The present invention relates to a color separating-combining optical system of a configuration having a separating optical system which separates light from a light source into a plurality of color spectrums; a combining optical system which combines light spectrums from a plurality of image display elements illuminated by the respective color spectrums; a filter which transmits a color spectrum of a specific wavelength band out of the plurality of color spectrums separated by the separating optical system; and a plurality of polarizing elements each disposed on the light entrance side of the plurality of image display elements, the polarizing elements being adapted to analyze the corresponding color spectrums incident to the respective image display elements. The color separating-combining optical system is further characterized in that the filter is placed apart from the polarizing element corresponding to the color spectrum transmitted by the filter.

Abstract: This invention discloses a projection type image display apparatus that includes a color separation optical system which separates illumination light into a plurality of chromatic rays of light, a plurality of image forming panels illuminated with the plurality of chromatic rays of light, respectively, a color synthesizing optical system which synthesizes rays of light emitted from the plurality of image forming panels illuminated therewith, and a plurality of cooling units which cool areas around the plurality of image forming panels, respectively, in which a cooling capacity (for example, specifications of a cooling unit or type of air-blowing fan) of at least one of the plurality of cooling units is different from those of the other cooling units. Thereby, cooling can be carried out most suitably for each color optical path, and cooling that is superior in efficiency and in balance can be carried out.

Abstract: The present invention relates to a color separating-combining optical system of a configuration having a separating optical system which separates light from a light source into a plurality of color spectrums; a combining optical system which combines light spectrums from a plurality of image display elements illuminated by the respective color spectrums; a filter which transmits a color spectrum of a specific wavelength band out of the plurality of color spectrums separated by the separating optical system; and a plurality of polarizing elements each disposed on the light entrance side of the plurality of image display elements, the polarizing elements being adapted to analyze the corresponding color spectrums incident to the respective image display elements. The color separating-combining optical system is further characterized in that the filter is placed apart from the polarizing element corresponding to the color spectrum transmitted by the filter.

Abstract: This invention discloses a projection type image display apparatus that includes a color separation optical system which separates illumination light into a plurality of chromatic rays of light, a plurality of image forming panels illuminated with the plurality of chromatic rays of light, respectively, a color synthesizing optical system which synthesizes rays of light emitted from the plurality of image forming panels illuminated therewith, and a plurality of cooling units which cool areas around the plurality of image forming panels, respectively, in which a cooling capacity (for example, specifications of a cooling unit or type of air-blowing fan) of at least one of the plurality of cooling units is different from those of the other cooling units. Thereby, cooling can be carried out most suitably for each color optical path, and cooling that is superior in efficiency and in balance can be carried out.