A vehicle display device includes a reflection-type hologram disposed inside a windshield of a vehicle, and a projection device including an image display device outputting a display light and a regulating unit configured to regulate a diffusion angle of the display light, and to project the display light having passed through the regulating unit onto the hologram. The hologram outputs the display light projected from the projection device as diffracted light directed to an eye range of the vehicle, and the regulating unit is configured to regulate the diffusion angle of the display light to an upper limit angle or less such that the display light reflected from the windshield is directed in a direction different from the eye range.

Provided a display apparatus including a light source configured to emit illumination light, a display panel configured to generate an image based on the illumination light, an image processor configured to provide image data to the display panel to cause the display panel to generate a first image and a second image which travel in different directions, and an optical system configured to separate the first image and the second image displayed on the display panel, wherein the image processor is further configured to provide the display panel with composite image data obtained by adding first image data to which a first phase profile is applied and second image data to which a second phase profile different from the first phase profile is applied.

An optical element of the present disclosure 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.

Reflection mode VHOEs are designed and fabricated for use in imaging and other applications that require high diffraction efficiency with minimal chromatic aberrations and astigmatism across the bandwidth. A single VHOE acts as a mirror to reflect light (0.sup.th diffraction order) at the specified wavelength(s) and bandwidth with a principal ray at an angle equal to an angle of incidence of broadband light. A composite VHOE includes a complementary pair of input and output VHOEs each configured to diffract light into a non-zero N.sup.th order. The input and output VHOEs are positioned in parallel to and offset from each other such that the filtered N.sup.th order beam exits the composite lens on a path at the angle of incidence and parallel to the broadband light while suppressing the unwanted 0.sup.th order beam. The composite lens improves suppression of unwanted wavelengths while still achieving minimal chromatic aberration.

A hologram display system is disclosed. An example system includes a hologram apparatus including a sheet folded along preformed creases into a frustum structure configured to be actuated between a compressed state and an uncompressed state. The frustum structure has a base section and a top section connected by four side sections. The system also includes instructions stored in a memory of a consumer device, which when executed, cause a processor of the consumer device to display, on a screen of the consumer device, holographic interactive content that is related to the hologram apparatus, detect interaction with at least one of the holographic interactive content or the hologram apparatus after the hologram apparatus is placed on the screen of the consumer device, and change the display of at least a portion of the holographic interactive content based on the detected interaction.

A device for producing a master diffraction grating includes a light source unit and a reflecting member 11. The light source unit forms a first interference fringe by irradiating a substrate surface of a master substrate 101 with light. The reflecting member 11 reflects the light from the light source unit reflected on the substrate surface of the master substrate 101 and guides the light again to the substrate surface side to form a second interference fringe. A resist pattern based on the first interference fringe and the second interference fringe is formed on the substrate surface of the master substrate 101.

Provided a holographic display apparatus including a light guide plate including an input coupler and an output coupler, a holographic image generating assembly configured to generate a holographic image and provide the holographic image to the input coupler of the light guide plate, and an image processor configured to convert source image data based on a point spread function, which is obtained for each pixel of the holographic image on an image plane, to compensate for a blur of the holographic image output through the output coupler.

Transmission and reflection mode VHOEs are designed and fabricated for use in imaging and other applications. These VHOE provide high diffraction efficiency with minimal chromatic aberrations and astigmatism across the bandwidth. The lens provides optical power within the bandwidth centered relative to several wavelengths to magnify (focus or collimate) input light and is transparent for the rest of the image spectrum. In transmission mode, two VHOE are fabricated in such a way as to introduce compensating adjustments that minimize the astigmatism and chromatic aberrations introduced by the bandwidth of the input light. Two VHOEs are required to provide an on-axis imaging system to magnify light to form an image and reduce the chromatic aberrations across the bandwidth and reduce the astigmatism while maintaining high diffraction efficiency (DE). In reflection mode, a single VHOE is configured to act as a mirror at the specified wavelength and bandwidth and to magnify light to form an image and, consequently, has minimal level of astigmatism and chromatic aberration.

An image display device of the present disclosure includes an image light generating device, a first, a second, a third, and a fourth optical unit. A first intermediate image is formed between the first and the third optical unit. A pupil is formed between the second and the fourth optical unit. A second intermediate image is formed between the third and the fourth optical unit. An exit pupil is formed at an opposite side of the fourth optical unit from the third optical unit. The image light generating device includes a first, a second, a third light emitting panel, and a color synthesis element. The color synthesis element is constituted of a cross dichroic prism including a first and a second dichroic film that intersect with each other. Each of the first and the second dichroic film does not have a polarization separation characteristic.

A reflector for vehicles includes a reflective surface that contains an optical element to reflect light incident on the optical element according to specific reflection characteristics. The reflective surface is designed as a hologram element which has a grating structure in such a way that light incident on the hologram element is reflected according to the specific reflection characteristics.