Provided are an optical element and an image display apparatus that display an aerial image, in which the total volume of the apparatus is small, a reduction in size can realized, and a scenery can be recognized. The optical element includes: a light guide element including a light guide plate, an incidence diffraction element, and an emission diffraction element, the incidence diffraction element being disposed on a main surface of the light guide plate and the emission diffraction element being disposed on the main surface of the light guide plate; and a positive lens that is disposed at a position overlapping the emission diffraction element in a view from a direction perpendicular to the main surface of the light guide plate, in which the incidence diffraction element diffracts incident light such that the diffracted light is incident into the light guide plate, the emission diffraction element emits light propagating in the light guide plate from the light guide plate, and the positive lens collects the light that is emitted from the light guide plate by the emission diffraction element.

An image display apparatus including one or more virtual-image screens, a display section, and a display control unit. The one or more virtual-image screens are arranged to cover at least a part of a periphery of a predetermined axis, display a virtual image of a projected image by using the predetermined axis as a basis, and are transparent. The display section has one or more display surfaces that display a plurality of viewpoint images in mutually different directions and project the plurality of displayed viewpoint images onto the one or more virtual-image screens, respectively, the plurality of viewpoint images being images of a display target as viewed from mutually different directions. The display control unit displays, a virtual image of the display target that is visible from a second direction extending toward the predetermined axis from the observation point.

A cluster according to an embodiment of the disclosure includes a display and a spatial image panel. The display is installed in the vehicle to output predetermined information as a 2D image. The spatial image panel is configured to output a 3D image in a predetermined space in front. The spatial image panel includes a first lens array, a second lens array, and a refractive medium. The first lens array is disposed adjacent to the display and includes a plurality of first lenses arranged on the same plane. The second lens array is disposed in parallel with the first array so that the first lenses and second lenses overlap each other. The refractive medium is disposed between the first lens array and the second lens array.

A display device includes a display capable of displaying an image, a beam-splitter that reflects light from the display, a retro-reflective member that reflects the light from the beam-splitter in the same direction as incident light, a first variable unit that varies an inclination angle of the display, and a second variable unit that varies an inclination angle of the beam-splitter, and prevents the image of the display from entering an aerial image.

One form of a display device of the present disclosure includes a first optical structure and a second optical structure stacked on the first optical structure. The first optical structure includes a light source, a light guide layer, a reflection layer, and a half mirror, and a light diffusion surface for generating a design of a multiple image that is formed on a bottom portion of the light guide layer. The second optical structure includes a light source, a light guide layer, a retroreflective layer, and a half mirror, and a light diffusion surface for generating a design of the aerial image is formed on a bottom portion of the light guide layer. The aerial image and the multiple image are simultaneously observed from the viewpoint of the user, and a sense of depth or a stereoscopic effect can be imparted to the aerial image.

An input device includes a display unit that displays an aerial image, and a detection unit that detects a user operation related to the aerial image. The display unit includes a light guide plate disposed between a half mirror and a retroreflective plate and a light source irradiating the light guide plate. The display unit displays the aerial image of a light diffusion surface formed on the light guide plate in response to incident light. When the user operation related to the aerial image is detected, the display unit turns off the light source to notify a user of input confirmation.

An input device includes a display unit that displays an aerial image, and a detection unit that detects a user operation related to the aerial image. The display unit includes a light guide plate disposed between a half mirror and a retroreflective plate and a light source irradiating the light guide plate. The display unit displays the aerial image of a light diffusion surface formed on the light guide plate in response to incident light. When the user operation related to the aerial image is detected, the display unit turns off the light source to notify a user of input confirmation.

A system for displaying three dimensional (3D) images. The system includes a 3D display operating in a first state to display a 3D image by outputting light into a viewing space and operating in a second state in which the 3D image is not displayed. The system further includes a screen element positioned between the 3D display and the viewing space. The screen element reflects light from the viewing space to appear opaque to a viewer in the viewing space when the 3D display operates in the second state. The screen element transmits the light output by the 3D display, whereby the 3D display image is perceivable by the viewer in the viewing space. The screen element includes a sheet of mesh or netting material that transmits light output by the 3D display through its pores or openings and may be a planar sheet of scrim or tulle.

A system for displaying three dimensional (3D) images. The system includes a 3D display operating in a first state to display a 3D image by outputting light into a viewing space and operating in a second state in which the 3D image is not displayed. The system further includes a screen element positioned between the 3D display and the viewing space. The screen element reflects light from the viewing space to appear opaque to a viewer in the viewing space when the 3D display operates in the second state. The screen element transmits the light output by the 3D display, whereby the 3D display image is perceivable by the viewer in the viewing space. The screen element includes a sheet of mesh or netting material that transmits light output by the 3D display through its pores or openings and may be a planar sheet of scrim or tulle.

Provided in the present application is a holographic display system, comprising an on-site holographic display system, a transmissive geometric holographic display system, a geometric holographic display system with folded optical path, and a reflective geometric holographic display system. A display element capable of directly displaying screens provided with depth of field information is used to project a diverging 3D image in the air without the aid of another reference light source. The image is converted by a projection screen of an equivalent negative refractive index flat lens to then obtain an observable 3D image suspended in the air, which reduces costs. At the same time, the 3D image may be displayed in front of or behind the projection screen, the display space is infinite, and in a very small device space, a super large screen and super deep depth of field may also be displayed.