A method for generating a holographic image, a signal processor, a holographic image display device, a wearable apparatus, and an onboard head-up display apparatus. The method comprises: performing holographic transformation on the basis of a target amplitude phase distribution of a target image to obtain a holographic phase image; performing phase quantization of the holographic phase image to obtain a quantized holographic image; performing inverse holographic transformation of the quantized holographic image to obtain a reconstructed image; if the reconstructed image satisfies a preset condition, determining that the quantized holographic image is a target holographic image; if not, constraining the amplitude phase of the reconstructed image and, on the basis of the amplitude phase constrained image, continuing iteration. The present method can rapidly and effectively implement monochrome or multi-colour high contrast ratio, low noise real-time holographic image generation and display, and the imaging distance can be freely adjusted.

Exemplary arrangements relate to methods for recording and reproducing holograms. A method of recording a hologram in a thresholded opto-magnetic medium (7) includes producing a collimated recording beam (1) with a pulsed laser. The intensity of the recording beam is selectively modulated by passage through a modulator (2). The recording beam is spatially shaped by passage through a shaping element (15). The shaped modulated recording beam is made convergent by passage through an aspheric lens (4). The convergent beam is deflected bidirectionally with a MEMS mirror (6) that is in operative connection with the modulator, such that multiple disposed locations on a surface of the medium are exposed to a constriction of the convergent shaped recording beam, causing a change in the medium in the locations. Reconstructing the hologram is carried out by illuminating the medium with a collimated laser beam and focusing with a lens, light from the illuminated medium onto a detection matrix. Additional methods of recording and reproducing holograms utilize alternative steps.

The display apparatus of the present disclosure includes an imaging light generating device and an optical system on which imaging light emitted from the imaging light generating device is incident. The optical system includes a first optical unit having positive power, a second optical unit having a positive power and including a first diffraction element, a third optical unit having positive power, and a fourth optical unit having positive power and including a second diffraction element forming an exit pupil, the first optical unit, the second optical unit, the third optical unit, and the fourth optical unit being aligned in order along an optical path of the imaging light. The second diffraction element is constituted of a volume hologram and has, in a cross-sectional view of the volume hologram, interference fringes continuously varying in pitch and inclination thereof from one end toward another end of the second diffraction element.

A spectacle lens for smartglasses can include at least one light source arrangement at the edge of the spectacle lens that emits coherent light, or at least one region at the edge of the spectacle lens for coupling in light from a light source arrangement that emits coherent light, or at least one light source arrangement that is embedded in the spectacle lens. A transparent or partly transparent display can provided to the spectacle lens such that coherent light emanating from the light source arrangement emits coherent light passing through the display or is reflected by the display. The wavefront of the coherent light is modulable in terms of its amplitude and/or its phase by an actuation of the display. A deformation device for deforming the wavefront of the coherent light before or after the modulation by the display can also be provided.

An augmented reality display system includes a first beam path for a foveal inset image on a holographic optical element, a second beam path for a peripheral display image on the holographic optical element, and pupil position tracking logic that generates control signals to set a position of the foveal inset as perceived through the holographic optical element, to determine the peripheral display image, and to control a moveable stage.

A head mounted display (HMD) system employs a holographic element in the optical path of the HMD to direct light to a user's eye. The HMD includes a micro-display, a lightguide, and a holographic element coupled to the lightguide. The holographic element is coupled to a polarization film, and together the element and film reflect and transmit light of different polarities in a specified pattern to assist the lightguide in directing light to the user's eye. For example, the hologram and polarization film can be configured to pass R-polarized light and reflect L-polarized light, thereby directing light from the waveguide along a specified path.

Examples are disclosed that relate to computing devices, head-mounted display devices, and methods for displaying holographic objects using slicing planes or volumes. In one example a computing device causes a display system to display a holographic object associated with a holographic volume, the holographic object occluding an occluded holographic object that is not displayed. Location data of at least a portion of a hand is received from a sensor. The location data of the hand is used to locate a slicing plane or a slicing volume within the holographic volume. Based on the location of the slicing plane or the slicing volume, at least a portion of the occluded holographic object is displayed via the display system.

A method includes projecting, with a holographic optical element, a first view of an eye toward an imaging device, and projecting, with the holographic optical element, a second view of the eye, distinct from the first view of the eye, toward the imaging device so that the first view and the second view of the eye are concurrently received by the imaging device. An eye tracking device for performing the method, a holographic optical element used for the method, and a method of making the holographic optical element are also disclosed.

Systems, articles, and methods that integrate photopolymer film with eyeglass lenses are described. One or more hologram(s) may be recorded into/onto the photopolymer file to enable the lens to be used as a transparent holographic combiner in a wearable heads-up display employing an image source, such as a microdisplay or a scanning laser projector. The methods of integrating photopolymer film with eyeglass lenses include: positioning photopolymer film in a lens mold and casting the lends around the photopolymer film; sandwiching photopolymer film in between two portions of a lens' applying photopolymer film to a concave surface of a lens' and/or affixing a planar carrier (with photopolymer film thereon) to two points across a length of a concave surface of a lens. Respective lenses manufactured/adapted by each of these processes are also described.

A system is provided. The system includes a light source configured to emit an infrared light to illuminate an eye of a user. The system includes a grating disposed facing the eye and including a birefringent material film configured with a uniform birefringence lower than or equal to 0.1. The grating is configured to diffract the infrared light reflected from the eye, and transmit a visible light from a real world environment toward the eye, with a diffraction efficiency less than a predetermined threshold. The system includes an optical sensor configured to receive the diffracted infrared light and generate an image of the eye based on the diffracted infrared light.