Abstract: A headlight apparatus configured to irradiate illumination light onto a road surface on which a vehicle travels includes a visible radiation lighting unit and a projector lens. The visible radiation lighting unit generates illumination light. The projector lens is provided on an optical axis of the visible radiation lighting unit, and is configured to distribute and project the illumination light irradiated from the visible radiation lighting unit. The visible radiation lighting unit has an LED, a liquid crystal display panel, and a shutter. The LED emits light. The liquid crystal display panel controls light distribution of the illumination light emitted from the LED. The shutter is provided between the liquid crystal display panel and the projector lens, and is configured to shield the liquid crystal display panel from solar light that enters through the projector lens.

Abstract: An information display apparatus and an information display method configured to display video information of a virtual image on a windshield of conveyance is provided. The information display apparatus includes: a display configured to display the video information; and a virtual image optical system configured to display a virtual image at a front of the conveyance by reflecting light emitted from the display by means of the windshield. The virtual image optical system includes a concave mirror and an optical element. A reflective film is formed on a reflecting surface of the concave mirror. A protective film for preventing moisture absorption is formed on a facing surface. By forming end surfaces of the two surfaces as a curved surface or an inclined surface and forming them on the end surfaces to block moisture, moisture absorption of plastic is prevented.

Abstract: An object of the present invention is to provide a compact head-up display device. The head-up display device of the present invention includes an image forming unit that emits image light containing image information, and an eyepiece optical system that displays a virtual image by reflecting the image light, in which the eyepiece optical system includes a concave lens, a free curved surface lens, and a free curved surface concave mirror disposed in order from the image forming unit side along the emission direction of the image light.

Abstract: A vehicular lighting apparatus which is relatively small, low cost, superior in mountability to an automobile, and superior in recognizeability of an object illuminated by a head lamp. The apparatus includes: a composite lens element that is a light guide element constructed by molding a translucent resin substantially into a plate-like shape; a planar light-emitting unit that emits light; an optical system that transforms planar light from the light-emitting unit into linear light and that causes the linear transformed light to be incident on a rear side face of the light guide element; and a diffraction lens formed on the rear side face of the light guide element on which the linear transformed light is incident, and condensing the linear transformed light. The light condensed by the lens means is emitted from a front side face of the light guide element onto a road surface in front of the vehicle.

Abstract: An information display apparatus is provided. The information display apparatus includes: a display configured to display video information of a virtual image; and a virtual image optical system configured to display a virtual image at a front of conveyance by reflecting light emitted from the display. The system includes a concave mirror and an optical element. The optical element is arranged between the display and the concave mirror, and is configured to correct distortion of the virtual image obtained in accordance with a viewpoint position of a driver. The information display apparatus further includes means for forming the virtual image generated by reflecting a video light flux by means of front and back surfaces of the windshield in front of a position of a driver's line of sight in a region where a virtual image distance exceeds a driver's determination limit range or a region around the determination limit range.

Abstract: A small-sized information display apparatus capable of displaying, as virtual images, different pieces of video image information at different positions in a wide area of a windshield. An embodiment has a virtual image optical system in which a flat display forming video image information is arranged, and that includes a projected member for causing virtual images to be displayed at a plurality of positions ahead of a vehicle by reflecting a video image on the flat display, thereby forming the virtual images at the plurality of positions so as to correspond to a viewpoint position of a driver. The virtual image optical system is arranged so that video image light fluxes for establishing the respective virtual images are separated from and independent of one another between the flat display and a concave mirror, and is configured by arranging different optical elements so as to correspond to the respective light fluxes.

Abstract: Provided is a method of producing spherical silver powder, which makes it possible to easily produce spherical silver powder having primary particle diameters with less variation than conventional powder and spherical silver powder obtained by the method. The method of producing spherical silver powder includes a reduction precipitation step of precipitating silver particles by reduction by adding a reductant including hydrazine carbonate to an aqueous reaction system containing silver ions.

Abstract: [Solution] Provided is a water purification agent suitable for use in an automated purification treatment device, when a wastewater purification treatment using a plant-derived water purification agent is performed with the automated purification treatment device. The water purification agent is a granulated product containing a mixture of a plant powder and a polymer coagulant.

Abstract: A headlight apparatus configured to irradiate illumination light onto a road surface on which a vehicle travels includes a visible radiation lighting unit and a projector lens. The visible radiation lighting unit generates illumination light. The projector lens is provided on an optical axis of the visible radiation lighting unit, and is configured to distribute and project the illumination light irradiated from the visible radiation lighting unit. The visible radiation lighting unit has an LED, a liquid crystal display panel, and a shutter. The LED emits light. The liquid crystal display panel controls light distribution of the illumination light emitted from the LED. The shutter is provided between the liquid crystal display panel and the projector lens, and is configured to shield the liquid crystal display panel from solar light that enters through the projector lens.

Abstract: A projection video display apparatus includes: a video projection screen, having a front and a rear surface, arranged in an indoor space. The video projection screen transmits video light from behind the rear surface or in front of the front surface to display video on the front surface. The front surface functions as a video display surface. A video projecting apparatus, arranged in a side of the rear surface or the front surface, enlarges and projects the video light from the rear or front surface. The video projecting apparatus is configured by an optical scanning video projecting apparatus that forms the video by scanning video light composed of coherent light on the video projection screen. The video projection screen guides the video light from the video projecting apparatus toward a direction to the front surface, and causes part of the light in the indoor space to be transmitted therethrough.

Abstract: An object of the invention is to provide an information display device that displays information in a vehicle, can reduce the movement of the viewpoint of a viewer, and can obtain a large amount of image information. In order to achieve the object, there is provided an information display device that displays information in a vehicle and includes a first information display device that displays image information of a virtual image using reflection from a windshield of the vehicle, a second information display device that scans the windshield with laser light using a MEMS element to obtain a real image, and a third information display device using an instrument panel of the vehicle.

Abstract: Provided is a light source apparatus that is small and lightweight, has high light utilization efficiency, and is easily utilizable as a modularized, planar light source. The light source apparatus 10 has a light source unit including a plurality of LED elements 14, a LED collimator 15 including a plurality of collimator elements each arranged on a light-emitting axis of each of the plural LED elements 14, and a light guide 17 disposed on an emission side of the LED collimator 15. The light guide 17 includes an incidence portion 171 having an incidence surface on which light on the light-emitting axis from the LED elements 14 is incident, and an emission portion 173c having an emission surface emitting light, and has a free-form surface shape for realizing predetermined light distribution control on at least one of the incidence surface and the emission surface.

Abstract: A HUD system and light source apparatus can be manufactured with miniaturization at low cost. A head-up display apparatus includes: an image display apparatus generating image light to be projected; an optical system performing predetermined correction to the image light emitted from the image display apparatus; and a concave mirror reflecting the image light corrected by the optical system to project it onto a windshield or combiner. The image display apparatus includes: a solid light source; a collimating optical system converting, into parallel light, the light from the solid light source; a lighting optical system configured by an optical member that polarizes a direction of a light beam generated by the collimating optical system and simultaneously expands a width of the light beam; and a display apparatus, the image display apparatus being configured to be arranged across and opposite the optical system on an optical axis of the concave mirror.

Abstract: Provided is a small-sized information display device displaying video image information as a virtual image by use of an eyepiece optical system including a concave mirror having desired reflection characteristics in a specific polarization direction, where a liquid crystal display panel is used as a video image light source. The information display device has a liquid crystal display panel as a flat display forming video image information disposed therein, and includes a virtual image optical system including a member to be projected for displaying virtual images in front of a vehicle by making a video image displayed on the liquid crystal display panel reflect on the member to be projected. The virtual image optical system includes a concave mirror, and a reflective film of the concave mirror has desired reflection characteristics in a specific polarization direction, so that virtual images having uniform brightness and chromaticity can be obtained.

Abstract: An information display apparatus capable of reducing the viewpoint movement of a driver and achieving safer driving in consideration of the relationship between the traveling speed and the stopping distance of a vehicle is provided. The information display apparatus is configured to display image information in a transportation and comprises a HUD apparatus disposed between a windshield of the transportation and an instrument panel of the transportation. The HUD apparatus detects a viewpoint position of a driver; and displays a virtual image of the image information in front of the transportation by reflecting light emitted from the HUD apparatus to display the image information by the windshield. The HUD apparatus is configured to set a display position of the virtual image in accordance with movement of the viewpoint position of the driver who is driving the transportation.

Abstract: A HUD system and light source apparatus can be manufactured with miniaturization at low cost. A head-up display apparatus includes: an image display apparatus generating image light to be projected; an optical system performing predetermined correction to the image light emitted from the image display apparatus; and a concave mirror reflecting the image light corrected by the optical system to project it onto a windshield or combiner. The image display apparatus includes: a solid light source; a collimating optical system converting, into parallel light, the light from the solid light source; a lighting optical system configured by an optical member that polarizes a direction of a light beam generated by the collimating optical system and simultaneously expands a width of the light beam; and a display apparatus, the image display apparatus being configured to be arranged across and opposite the optical system on an optical axis of the concave mirror.

Abstract: A projection-type image display apparatus has a projection optical system that can sufficiently meet requirements for significant reduction in a throw distance and a large image and that can downsize. A projection image display apparatus of an oblique type comprising, inside a housing: a light source; an image display element configured to modulate an intensity of light from the light source in accordance with an image signal; and a projection lens system including a plurality of lenses configured to project image light onto a projection plane from an oblique direction, the image light being modulated from the image display element. The projection lens system has a lens integrally having an aspherical lens surface and a freeform lens surface, and the lens integrally having the aspherical lens surface and the freeform lens surface is arranged in the projection lens system so that light components of luminous flux are separated.

Abstract: Provided is an information display apparatus that significantly improves light resistance with respect to sunlight. The information display apparatus, which displays video-image information on a projection surface by a virtual image, includes in a housing partly having an opening: a video-image-light generator that generates video-image light for displaying the video-image information; a video-image-light processor that performs a predetermined optical processing to a video image generated by the video-image-light generator; and a projector that projects, onto the projection surface through the opening of the housing, the video-image light optically processed by the video-image-light processor so that a viewer is capable of virtually recognizing the video-image information as a virtual image in front of the projection surface, wherein a light path in the housing is provided with a suppressor selectively suppressing a P-polarizing component of light in a visible light region.

Abstract: A projection video display apparatus and method for solving a problem of deterioration of visibility of video that is projected on a transparent or semi-transparent screen. In a projection video display method for projecting and displaying video light on a rear surface or front surface of a transparent or semi-transparent video projection screen disposed in a space by a projection video display apparatus, video light to be projected and displayed is generated, the generated video light is projected on the rear surface or front surface of the transparent or semi-transparent video projection screen, and at that time, a video display position recognition screen for making an observer of the video recognize a position where the video is projected is projected on the transparent or semi-transparent video projection screen before start of the projection of the video light or simultaneously with the start of the projection of the video light.

Abstract: Provided is a compact light source device that can be manufactured at a low cost and is suitable as an illumination light source for a display device of an electronic device such as an HUD or an ultra-compact projector. This light source device includes a solid-state light source, a collimating optical system that converts light having exited the solid-state light source into a substantially collimated light; and a light guide that allows the light having exited the collimating optical system to enter and allows this light to exit in a direction that differs from a direction of entry. The light source device further includes a polarization converting element that aligns polarization directions of the light exiting the light guide into one direction.