Abstract: A braking force control apparatus includes: a prediction unit that predicts a time from a present time until a next start of the gear shift operation in the stepped automatic transmission based on a speed of the vehicle; an acquisition unit that acquires a state of a battery charged by a regenerative power generation of the regenerative generator; and a control unit that stops the regenerative power generation by the regenerative generator before the gear shift of the stepped automatic transmission is started, when it is determined, during the regenerative power generation by the regenerative generator, that the regenerative power generation by the regenerative power generator may be stopped due to the state of the battery during the gear shift operation of the stepped automatic transmission, based on a prediction result by the prediction unit and the state of the battery acquired by the acquisition unit.

Abstract: A braking force control apparatus includes: a prediction unit that predicts a time from a present time until a next start of the gear shift operation in the stepped automatic transmission based on a speed of the vehicle; an acquisition unit that acquires a state of a battery charged by a regenerative power generation of the regenerative generator; and a control unit that stops the regenerative power generation by the regenerative generator before the gear shift of the stepped automatic transmission is started, when it is determined, during the regenerative power generation by the regenerative generator, that the regenerative power generation by the regenerative power generator may be stopped due to the state of the battery during the gear shift operation of the stepped automatic transmission, based on a prediction result by the prediction unit and the state of the battery acquired by the acquisition unit.

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 braking force control apparatus includes: a prediction unit that predicts a time from a present time until a next start of the gear shift operation in the stepped automatic transmission based on a speed of the vehicle; an acquisition unit that acquires a state of a battery charged by a regenerative power generation of the regenerative generator; and a control unit that stops the regenerative power generation by the regenerative generator before the gear shift of the stepped automatic transmission is started, when it is determined, during the regenerative power generation by the regenerative generator, that the regenerative power generation by the regenerative power generator may be stopped due to the state of the battery during the gear shift operation of the stepped automatic transmission, based on a prediction result by the prediction unit and the state of the battery acquired by the acquisition unit.

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 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: 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 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 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: 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 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.

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.