A holographic projector includes a spatial light modulator, a light receiving member and a driver. The spatial light modulator is arranged to receive and represent a computer-generated hologram and spatially modulate light incident on the spatial light modulator to form a holographic reconstruction in accordance with the computer-generated hologram. The light receiving member is arranged to receive spatially modulated light along an optical axis from the spatial light modulator and the holographic reconstruction is formed on the light receiving member. The driver is coupled to the light receiving member to move the light receiving member in a plane. The driver is configured to move the light receiving member while maintaining an orientation of the light receiving member relative to the spatial light modulator substantially constant.

A system and method comprise a light source; a spatial light modulator including a substantially transparent material layer and a phase modulation layer; an imaging device configured to receive a light from the light source as reflected by the spatial light modulator, and to generate an image data; and a controller. The controller provides a phase-drive signal to the spatial light modulator and determines an attenuating wavefront of the substantially transparent material layer based on the image data.

A novel spatial light modulator (SLM) includes a cover glass, and modulation layer, and a plurality of pixel mirrors, and separates unwanted, reflected light from desired, modulated light. In one embodiment, a geometrical relationship exists between the cover glass and the pixel mirrors, such that light that reflects from the cover glass is separated from light that reflects from the pixel mirrors and is transmitted from the SLM. In one example, one of the cover glass or the pixel mirrors is angled with respect to the modulation layer. In another example embodiment, the cover glass has a particular thickness, which introduces destructive interference between light that reflects from the top and bottom surfaces of the cover glass. In another embodiment antireflective coatings are disposed between optical interfaces of the SLM. In another embodiment, light from the SLM is directed through an optical filter to remove unwanted light.

There is provided a method of projection using an optical element (502,602) having spatially variant optical power. The method comprises combining Fourier domain data representative of a 2D image with Fourier domain data having a first lensing effect (604a) to produce first holographic data. Light is spatially modulated (504,603a) with the first holographic data to form a first spatially modulated light beam. The first spatially modulated light beam is redirected using the optical element (502,602) by illuminating a first region (607) of the optical element (602) with the first spatially modulated beam. The first lensing effect (604a) compensates for the optical power of the optical element in the first region (607). Advantageous embodiments relate to a head-up display for a vehicle using the vehicle windscreen (502,602) as an optical element to redirect light to the viewer (505,609).

There is provided a head-up display for a vehicle having a window. The head-up display comprises a picture generating unit (410) and an optical system (420). The picture generating unit is arranged to output pictures. The optical system is arranged to receive the pictures output by the picture generating unit and project the pictures onto the window (430) of the vehicle to form a virtual image (450, 707) of each picture within a virtual image area (605). The picture generating unit is arranged to output pictures within a cropped picture area such that the virtual image area (605) has a corresponding cropped shape. FIG. 7 illustrates a perspective view of a three lanes road (501,502,503) onto which a virtual image (707) within a cropped virtual image area (605) is overlaid.

A display apparatus includes a coherent light source, a display unit, a light-diffusing element, and at least one optical element. The coherent light source is configured to provide coherent light beams. The display unit is configured to form a three-dimensional image beam based on interference of the coherent light beams, wherein the three-dimensional image beam is imaged on an intermediate imaging surface after passing through the display unit. The light-diffusing element is located on the intermediate imaging surface, wherein a diffusion angle of the three-dimensional image beam is sequentially changed by passing through the light-diffusing element. The at least one optical element is located on a transmission path of the three-dimensional image beam from the light-diffusing element, and is configured to project the three-dimensional image light beam passing through the display unit out of the display apparatus to display a three-dimensional image.

An illumination device includes a light diffusion device including element diffusion devices that diffuse incident light, a coherent light source that emits coherent light, a shaping optical system that shapes the coherent light, a scanner that adjusts a traveling direction of the coherent light so as to allow the coherent light to scan the light diffusion device, and a light condensing optical system located on a light path of the coherent light from the shaping optical system up to the light diffusion device. The light condensing optical system condenses the coherent light such that a spot area on the light diffusion device is smaller than the element diffusion device. Each element diffusion device diffuses the coherent light incident thereon so as to illuminate an element illumination area corresponding to the element diffusion device.

There is provided a method of projection using an optical element (502,602) having spatially variant optical power. The method comprises combining Fourier domain data representative of a 2D image with Fourier domain data having a first lensing effect (604a) to produce first holographic data. Light is spatially modulated (504,603a) with the first holographic data to form a first spatially modulated light beam. The first spatially modulated light beam is redirected using the optical element (502,602) by illuminating a first region (607) of the optical element (602) with the first spatially modulated beam. The first lensing effect (604a) compensates for the optical power of the optical element in the first region (607). Advantageous embodiments relate to a head-up display for a vehicle using the vehicle windscreen (502,602) as an optical element to redirect light to the viewer (505,609).

There is provided a head-up display for a vehicle having a window. The head-up display comprises a picture generating unit (410) and an optical system (420). The picture generating unit is arranged to output pictures. The optical system is arranged to receive the pictures output by the picture generating unit and project the pictures onto the window (430) of the vehicle to form a virtual image (450, 707) of each picture within a virtual image area (605). The picture generating unit is arranged to output pictures within a cropped picture area such that the virtual image area (605) has a corresponding cropped shape. FIG. 7 illustrates a perspective view of a three lanes road (501,502,503) onto which a virtual image (707) within a cropped virtual image area (605) is overlaid.

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.