Abstract: A compact head-up display device is provided. For that purpose, the head-up display device includes a projection optical system which includes an image forming unit to display image information and an ocular optical system to reflect light emitted from the image forming unit to display a virtual image. In the ocular optical system, a free-form surface lens and a free-form surface concave mirror are arranged in order from the image forming unit. The shape of the free-form surface concave mirror is such that curvature radius RY1 in projection on a vertical cross section of the coordinate system of an eye-box is smaller than curvature radius RX1 in projection on a horizontal cross section.

Abstract: A head-up display device that displays information including a video in a part of a field of view of an operator (407) includes a video display device (420) that is arranged at a position deviated from the field of view of the operator and generates and projects video light for projecting the information and a transparent screen (410) that is arranged in a part of the field of view of the operator, and transmit light from the field of view and reflects projection light from the video display device in a direction of the operator. A solid-state light source device (421) that reflects and mixes light emitted from a plurality of light-emitting cells (40) and emits the light obtained by the mixing in a predetermined direction is used as a light source constituting the video display device.

Abstract: A vehicular lighting apparatus is relatively small, low cost, superior in mountability, and offers a superior design. The vehicular lighting apparatus attachable to a front end of a vehicle 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 illumination 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: A small information display apparatus capable of displaying video information on a windshield as a virtual image is provided. An information display apparatus configured to display video information of a virtual image on a windshield of a conveyance includes: a liquid crystal panel arranged as a video display apparatus configured to form the video information; and a virtual image optical system provided with a windshield for displaying the virtual image at a front of the conveyance by reflecting video of the liquid crystal panel by means of the windshield. The virtual image optical system is configured by arranging a concave mirror and an optical element between the concave mirror and the video display apparatus.

Abstract: A free-form surface lens is made of a transparent resin forming an oblique projection optical system including a free-form surface mirror in a projection type video display apparatus, this lens includes a lens effective region having a surface on which a predetermined free-form surface is formed, and an edge surface formed to surround the lens effective region, the lens effective region and the edge surface in a part of a circumference surrounding the lens effective region where the edge surface is not formed are joined to each other by at least either one of a curved surface and a flat surface set so as not to change a direction of a tilt of the lens effective region in vicinity of the lens effective region, and an end surface including at least either one of the curved surface and the flat surface is set as a tapered surface.

Abstract: Methods for manufacturing a rotational non-axisymmetric lens which is manufactured by grinding using a machining tool, manufacturing a molding die for the lens, manufacturing a rotational non-axisymmetric mirror, and manufacturing a molding die for the mirror are provided. The provided methods are methods for manufacturing a rotational non-axisymmetric lens partially including a non-axisymmetric surface, manufacturing a molding die for the lens, manufacturing a rotational non-axisymmetric mirror partially including a non-axisymmetric surface, and manufacturing a molding die for the mirror. When a rotational non-axisymmetric surface is formed while scanning a surface of a workpiece by grinding or cutting means, the rotational non-axisymmetric surface is ground or cut by the grinding or cutting means while scanning the surface with movement in a direction along a meridional surface of the rotational non-axisymmetric surface.

Abstract: A headlight device (1) having a projection function includes a light source device (2), a lighting optical system (3), an image display element (4), an image signal controller (6), and a projection optical system (5). The projection optical system (5) includes a coaxial lens system (11) having a refractive action, a free-form surface lens (12), and a free-form surface mirror (13) from the image display element (4) side. In this way, an image that can be readily visually recognized by a driver or a pedestrian may be projected onto a road.

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: A free-form surface lens is made of a transparent resin forming an oblique projection optical system including a free-form surface mirror in a projection type video display apparatus, this lens includes a lens effective region having a surface on which a predetermined free-form surface is formed, and an edge surface formed to surround the lens effective region, the lens effective region and the edge surface in a part of a circumference surrounding the lens effective region where the edge surface is not formed are joined to each other by at least either one of a curved surface and a flat surface set so as not to change a direction of a tilt of the lens effective region in vicinity of the lens effective region, and an end surface including at least either one of the curved surface and the flat surface is set as a tapered surface.

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: 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: A vehicular lighting apparatus is relatively small, low cost, superior in mountability, and offers a superior design. The vehicular lighting apparatus attachable to a front end of a vehicle 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 illumination 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: A head-up display device includes: an image formation unit which emits light including image information; and a projection optical system including an ocular optical system which displays a virtual image by reflecting the light emitted from the image formation unit. The ocular optical system includes spherical lenses, a free-form curved surface lens, a reflection mirror, and a free-form curved surface mirror, and is configured by arranging, in a space on the side of the ocular optical system of a plane conjugate with the virtual image plane with respect to the ocular optical system, a first small lens system which achieves first focus position movement and on which separated light from the image formation unit is made to be incident, and a second small lens system which achieves second focus position movement and on which separated light from the image formation unit is made to be incident.

Abstract: Provided is a head-up display device which has a virtual image plane shape becoming a part of a concave shape as viewed from the driver side. This head-up display device (30) includes: an image forming unit (10) that displays image information; and a projection optical system including an ocular optical system (5) that displays a virtual image by reflecting light emitted from the image forming unit (10). The ocular optical system (5) includes spherical lenses (51), (52), (53), and a free-form curved surface mirror (56), and is configured by arranging the spherical lenses (51), (52), (53) and the free-form curved surface mirror (56) in this order along the light emission direction.

Abstract: A vehicular lighting apparatus which is relatively small, lower in cost, and superior in recognizeability of an object illuminated by a head lamp 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: A vehicular lighting apparatus that is relatively small, low cost, superior in mountability, and offers a superior design. The vehicular lighting apparatus may include 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 illumination 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: Provided is a projection lens assembly method in an oblique projection optical system, which enables efficient manufacture even if a size of an image display element to be mounted varies, and a projection type image display apparatus using the projection lens. The projection lens assembly method in the oblique projection optical system for an oblique type projection image display apparatus including a block of a spherical lens and a block of an aspherical lens includes: preparing in advance the block of the spherical lens having a size that adapts to image display elements having different sizes and incorporated in the projection image display apparatus, and the block of a common aspherical lens; and assembling the block of the spherical lens selected in accordance with the sizes of the incorporated image display elements and the block of the common aspherical lens to assemble the projection lens.

Abstract: A head-up display apparatus is provided which enables a wide viewing angle in spite of being a type that reflects image light on a windshield. Accordingly, a head-up display apparatus (110) includes an image formation unit (10) that displays image information, and a projection optical system that includes an eyepiece optical system 5 reflecting light emitted from the image formation unit (10) for display of a virtual image. The eyepiece optical system (5) includes a first optical element (51) having a negative refractive power, a second optical element (52) having a positive refractive power, and a concave reflecting mirror (54), and is configured to arrange the first optical element (51), the second optical element (52) and the reflecting mirror (53) in this order from the image formation unit.

Abstract: A projection type image display device includes an oblique projection optical system that magnifies and projects modulated image light, and includes lens elements and a reflection mirror having a convex surface. A center of an outer shape of one or more of the lens elements at a nearest position to the reflection mirror is positioned above an optical axis. The reflection mirror has a reflection surface shape orthogonal to a projection plane inclusive of the optical axis of the reflection mirror. The reflection surface shape and lens element are formed as specified. For example, the reflection surface shape is formed so that an average radius of curvature in an area through which a light flux focused at a center of the projection plane passes is smaller than that of curvature in an area through which a light flux focused at an upper end portion of the projection plane passes.

Abstract: Methods for manufacturing a rotational non-axisymmetric lens which is manufactured by grinding using a machining tool, manufacturing a molding die for the lens, manufacturing a rotational non-axisymmetric mirror, and manufacturing a molding die for the mirror are provided. The provided methods are methods for manufacturing a rotational non-axisymmetric lens partially including a non-axisymmetric surface, manufacturing a molding die for the lens, manufacturing a rotational non-axisymmetric mirror partially including a non-axisymmetric surface, and manufacturing a molding die for the mirror. When a rotational non-axisymmetric surface is formed while scanning a surface of a workpiece by grinding or cutting means, the rotational non-axisymmetric surface is ground or cut by the grinding or cutting means while scanning the surface with movement in a direction along a meridional surface of the rotational non-axisymmetric surface.