An optical device includes a first plate having a first transparent region defining an exit face of the device, and a second plate having a second transparent region defining an entrance face of the device. At least one lens is formed over at least one of the first and second transparent regions. First and second planar reflectors are spaced apart and fixed between the first and second plates in mutually-parallel orientations diagonal to the first and second plates, thereby defining an optical path through the device from the entrance face, reflecting from the first and second reflectors, through the exit face and passing through the at least one refractive surface.

The present disclosure relates to structured illumination. The teachings thereof may be embodied in devices for reconstruction of a three-dimensional surface of an object by means of a structured illumination for projection of measurement patterns onto the object. For example, a device may include: a projector unit for diffractive projection of a measurement pattern comprising a plurality of measurement points onto the surface; an acquisition unit for acquiring the measurement pattern from the surface; and a computer unit for reconstruction of the surface from a respective distortion of the measurement pattern. All possible positions of measurement elements are contained in the measurement pattern in repeating groups, in which a respective combination of measurement points represents a respective location in the measurement pattern.

Three-dimensional (3D) electronic displays provide different 3D views and employ one or both of an array of multibeam diffraction gratings arranged in offset rows and light valves having color filters. The displays include a plate light guide configured to guide light beams at a non-zero propagation angle, a multibeam diffraction grating configured to couple out a portion of the guided light beams as a plurality of light beams having different principal angular directions representing the different 3D views, and light valves configured to modulate the differently directed, coupled-out light beams. The multibeam diffraction grating may be a member of the array arranged in offset rows and the display may further include light valves having color filters. Alternately, the light valves include color filters and the display may further include the array of multibeam diffraction gratings arranged in offset rows.

A waveguide display includes a waveguide and a staircase structure coupled to the waveguide. The waveguide includes a first substrate, a second substrate, and a holographic material layer between the first substrate and the second substrate. The holographic material layer includes a first grating and a second grating. The staircase structure is positioned on top of at least a portion of the first grating but not on top of the second grating. The staircase structure includes an input grating that is on top of the first grating and is configured to couple display light into the waveguide. The first grating is configured to redirect the display light coupled into the waveguide by the input grating towards the second grating.

There is provided an illumination device comprising: a laser; a waveguide comprising at least first and second transparent lamina; a first grating device for coupling light from the laser into a TIR path in the waveguide; a second grating device for coupling light from the TIR path out of the waveguide; and a third grating device for applying a variation of at least one of beam deflection, phase retardation or polarization rotation across the wavefronts of the TIR light. The first second and third grating devices are each sandwiched by transparent lamina.

An optical arrangement for spectral decomposition of light is disclosed. In an embodiment the optical arrangement includes a reflection diffraction grating, a first medium with a refractive index n.sub.in arranged on a light incidence side of the reflection diffraction grating; and a second medium with a refractive index n.sub.G arranged on a side of the reflection diffraction grating that faces away from the light incidence side, with n.sub.in>n.sub.G, wherein the optical arrangement is configured in such a way that light impinges on the reflection diffraction grating from the first medium at an angle of incidence α, wherein a condition sin(α)>n.sub.G/n.sub.in is satisfied, wherein the reflection diffraction grating comprises a layer system with at least one unstructured layer and at least one structured layer, wherein the at least one structured layer has a periodic structure with a period p in lateral direction, and wherein the period p meets the following conditions: p<λ/[n.sub.in*sin(α)+n.sub.G] and p>λ/[n.sub.in*sin(α)+n.sub.in].

Fiducial patterns that produce 2D Barker code-like diffraction patterns at a camera sensor are etched or otherwise provided on a cover glass in front of a camera. 2D Barker code kernels, when cross-correlated with the diffraction patterns captured in images by the camera, provide sharp cross-correlation peaks. Misalignment of the cover glass with respect to the camera can be derived by detecting shifts in the location of the detected peaks with respect to calibrated locations. Devices that include multiple cameras behind a cover glass with one or more fiducials on the cover glass in front of each camera are also described. The diffraction patterns caused by the fiducials at the various cameras may be analyzed to detect movement or distortion of the cover glass in multiple degrees of freedom.

A virtual image generation system comprises a planar optical waveguide having opposing first and second faces, an in-coupling (IC) element configured for optically coupling a collimated light beam from an image projection assembly into the planar optical waveguide as an in-coupled light beam, a first orthogonal pupil expansion (OPE) element associated with the first face of the planar optical waveguide for splitting the in-coupled light beam into a first set of orthogonal light beamlets, a second orthogonal pupil expansion (OPE) element associated with the second face of the planar optical waveguide for splitting the in-coupled light beam into a second set of orthogonal light beamlets, and an exit pupil expansion (EPE) element associated with the planar optical waveguide for splitting the first and second sets of orthogonal light beamlets into an array of out-coupled light beamlets that exit the planar optical waveguide.

A virtual image generation system comprises a planar optical waveguide having opposing first and second faces, an in-coupling (IC) element configured for optically coupling a collimated light beam from an image projection assembly into the planar optical waveguide as an in-coupled light beam, a first orthogonal pupil expansion (OPE) element associated with the first face of the planar optical waveguide for splitting the in-coupled light beam into a first set of orthogonal light beamlets, a second orthogonal pupil expansion (OPE) element associated with the second face of the planar optical waveguide for splitting the in-coupled light beam into a second set of orthogonal light beamlets, and an exit pupil expansion (EPE) element associated with the planar optical waveguide for splitting the first and second sets of orthogonal light beamlets into an array of out-coupled light beamlets that exit the planar optical waveguide.

Examples are disclosed that relate to a compact optical systems comprising SLMs. One example provides a projection system comprising an illumination stage including a light emitting diode (LED) array. The LED array comprises a plurality of red LEDs, a plurality of green LEDs, and a plurality of blue LEDs. The illumination stage further comprises an illumination stage optical system configured to control an angular extent of light emitted by the LED array and homogenize the light emitted by the LED array. The projection system further comprises an image forming stage configured to form an image from light output by the illumination stage, the image forming stage comprising a spatial light modulator (SLM) configured to spatially modulate the light output by the illumination stage to form an image, and one or more projection optics configured to project the image formed by the spatial light modulator.