A head-up display is configured to project an image on a transparent reflection member to cause an observer to visually recognize a virtual image, and includes a display device configured to display the image, and a projection optical system configured to project the image displayed by the display device as the virtual image for the observer. The projection optical system is configured to form an image as an intermediate image, and includes a first lens configured to condense light, and a first optical element configured to diffuse light. The first lens and the first optical element are disposed in this order along an optical path from the display device. The first lens is inclined with respect to a reference beam which is defined as a beam reaching a center of a viewpoint region of the observer and corresponding to a center of the virtual image.

A head-mounted imaging apparatus has a projector that is energizable to project image-bearing light and a light-conditioning element that directs and shapes the image-bearing light from the projector to form a real image plane. A lenslet array is positioned adjacent to the real image plane and optically disposed at substantially one focal length away from a curved mirror, wherein the surface of the curved mirror is substantially spherical. There is a beamsplitter in the path of light from the real image at the lenslet array and disposed to direct at least a portion of the light from the real image toward the curved mirror. The curved mirror directs light from the beamsplitter to form a virtual image for an observer who wears the head-mounted imaging apparatus.

A near-to-eye display device includes a spatial light modulator, a rotatable reflective optical element and a pupil-tracking device. The pupil-tracking device tracks the eye pupil position of the user. Based on the data provided by the pupil-tracking device, the reflective optical element is rotated such that the light modulated by the spatial light modulator is directed towards the user's eye pupil.

An image display apparatus mountable on a mobile object includes an image light generator and a transmissive member. The image light generator is configured to generate image light and emit the image light to a transmission and reflection member mounted on the mobile object. The transmissive member is disposed in an optical path of the image light between the image light generator and the transmission and reflection member. The transmissive member is configured to transmit the image light from the image light generator. The transmissive member has a cross section with a predetermined curve, the cross section being orthogonal to a predetermined direction inclined with reference to a virtual plane orthogonal to a horizontal direction of the mobile object.

There is disclosed herein a waveguide comprising an optical slab and an optical wedge. The optical slab has a first refractive index, n.sub.1>1. The optical slab comprises: a pair of opposing surfaces and an input port. The pair of opposing surfaces are arranged in a parallel configuration. The input port is arranged to receive light into the optical slab at an angle such that the light is guided between the first and second opposing surfaces by a series of internal reflections. The optical wedge has a second refractive index, n.sub.2, wherein 1<n.sub.2<n.sub.1. The optical wedge comprises a pair of opposing surfaces arranged in a wedge configuration. A first surface of the optical wedge abuts the second surface of the optical slab to form an interface that allows partial transmission of light guided by the optical slab into the optical wedge at a plurality of points along the interface such that the light is divided a plurality of times. The angle of the wedge allows light received at the interface to escape through the second surface of the optical wedge such that the exit pupil of the waveguide is expanded by the plurality of divisions of the light.

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.

A head up display assembly includes an optical system (52) and a transmissive display. A light source is configured to projected a light through the transmissive display. A diffuser (64) is located between the optical system and the transmissive display (62).

An optical element includes a hologram layer, a resin substrate to which the hologram layer is adhered, and a holder portion that supports the resin substrate and has a thermal expansion coefficient smaller than that of the resin substrate. One of the holder portion and the resin substrate includes a contact surface along an axis extending in a plate thickness direction of the resin substrate, and the other of the holder portion and the resin substrate includes a pressing surface that presses the contact surface.

A head-up display has a display element, a projection system, a diffusing plate, and a mirror element. In such head-up displays, frequently irritations due to stray light occur. A head-up display that produces less irritation from incident stray light is therefore desirable. The diffusing plate has focusing elements on its side facing the projection system and a light-blocking mask on its side facing away from the projection system.

A head for a walk-around costume is provided that is adapted for enhanced visibility. The costume head includes an outer shell defining an interior space for receiving a head of a human performer. The outer shell includes an aperture allowing incoming light from an exterior space to enter the interior space, and an eye location for the human performer is spaced apart from the aperture when the head is received in the interior space. To provide an enlarged field of view, the costume head includes an optical viewfinder assembly disposed within the interior space of the outer shell between the aperture and the eye location. The optical viewfinder assembly is adapted for receiving the incoming light and transmitting the incoming light to the eye location to move a viewpoint of the human performer to the aperture to provide a larger field of view of the exterior space.