A method of producing information from at least one camera image of an object, including: A) recording raw image data of the at least one camera image, B) evaluating the raw image data by a mathematical linkage to produce combination image data, C) deriving the information from the combination image data, D) outputting the information, E) determining an actual measure for a data quality of the raw image data prior to or after evaluation steps in step B), F) determining a deviation between the actual measure for the data quality and a target measure for the data quality of the raw image data of at least one camera image, and G) again recording all raw image data of those camera images, for which the deviation determined in step F) is greater than a predetermined threshold value and repeating at least one evaluation step from step B) and steps C) to F) either until the deviation determined in step F) for the raw image data of all camera images from the plurality of camera images is less than the threshold value or until a predetermined termination condition is fulfilled.

A projection system and method includes a light source configured to emit a light in response to an image data; a phase light modulator configured to receive the light from the light source and to apply a spatially-varying phase modulation on the light; and a controller configured to determine, for a frame of the image data, a plurality of phase configurations, respective ones of the plurality of phase configurations corresponding to solutions of a phase algorithm and representing the same image with a different modulation pattern, and provide a phase control signal to the phase light modulator, the phase control signal configured to cause the phase light modulator to modulate the plurality of phase configurations in a time-divisional manner within a time period of the frame, thereby to project a series of subframes within the time period.

A method and display apparatus for reducing holographic speckle when displaying holographic images are described. A target image (10) is decomposed into input images (11). A first input image includes higher spatial frequency components of the target image and is imaged using a first display method (12) to generate a first holographic display image. The second input image includes lower spatial frequency components of the target image and is imaged using a second display method (12) to generate a second display image. The first and second display images are combined for display to a user. The second display method (12) is adapted to reduce holographic speckle or include no holographic speckle compared to the first holographic display method (12) thereby reducing holographic speckle in the combined display image (13).

A holographic display is comprised of space-multiplexed elemental modulators, each of which consists of a surface acoustic wave transducer atop an anisotropic waveguide. Each “line” of the overall display consists of a single anisotropic waveguide across the display's length with multiple surface acoustic wave transducers spaced along the waveguide length, although for larger displays, the waveguide may be divided into segments, each provided with separate illumination. Light that is undiffracted by a specific transducer is available for diffraction by subsequent transducers. Per transducer, guided-mode light is mode-converted to leaky-mode light, which propagates into the substrate away from the viewer before encountering a volume reflection grating and being reflected and steered towards the viewer. The display is transparent and all reflection volume gratings operate in the Bragg regime, thereby creating no dispersion of ambient light.

Various examples of out-of-plane multicolor waveguide holography systems, methods of manufacture, and methods of use are described herein. In some examples, a multicolor waveguide holography system includes a planar waveguide to convey optical radiation between a grating coupler and a metasurface hologram. The grating coupler may be configured to couple out-of-plane optical radiation of three different color incident at three different angles into the planar waveguide. The combined multicolor optical radiation may be conveyed by the waveguide to the metasurface hologram. The metasurface hologram may diffractively decouple the three colors of optical radiation for off-plane propagation to form a multicolor holographic image in free space.

An optical identifier including a recording surface, a plurality of deflection cells each of which has recorded thereon a range in which light to be diffracted is deflected, at least one spatial phase modulator which fills a space between the deflection cells on the recording surface, and a deposition layer which covers part or all of the recording surface. The deflection cells has a spatial frequency expressed in a form of a relief structure and are discretely formed on the recording surface at regular intervals away from each other. A variable color image is recorded by pixels defined by the deflection cells. The spatial phase modulator has thereon a distribution of phase differences recorded in a form of heights of the relief structure. The spatial phase modulator modulates a phase of light outputted from a point light source and displays a reproduced image.

A grating coupler may be fabricated by exposing a photopolymer layer to grating forming light for forming periodic refractive index variations in the photopolymer layer. The photopolymer layer may be exposed to apodization light for reducing an amplitude of the periodic refractive index variations in a spatially-selective manner. The apodization may also be achieved or facilitated by subjecting outer surface(s) of the photopolymer layer to a chemically reactive agent that causes the refractive index contrast to be reduced near the surface(s) of application. The apodized refractive index profile of the gratings facilitates the reduction of optical crosstalk between different gratings of the grating coupler.

A holographic projector comprises an image processing engine arranged to, a hologram engine and a display engine. The image processing engine is arranged to receive a source image for projection. The source image comprises a first colour component and a second colour component. The image processing engine is further arranged to form a first colour secondary image from the first colour component by nulling alternate pixel values of the first colour component in accordance with a first checkerboard pattern. The image processing engine is further arranged to form a second colour secondary image from the second colour component by nulling alternate pixel values of the second colour component in accordance with a second checkerboard pattern. The first checkerboard pattern is opposite to the second checkerboard pattern. The hologram engine is arranged to determine a first colour hologram corresponding to the first colour secondary image and a second colour hologram corresponding to the second colour secondary image. The display engine is arranged to form a first colour holographic reconstruction from the first colour hologram and a second colour holographic reconstruction from the second colour hologram.

An interference imaging device includes a light interference generator that includes: a light wave splitter configured to reflect a part of incident light and to allow a remaining part of the incident light to pass through; a phase modulator configured to modulate a phase of incident light that has passed through the light wave splitter; and a reflector configured to reflect the phase-modulated incident light from the phase modulator so that the reflected, phase-modulated incident light overlaps with incident light that has been reflected by the light wave splitter.

A method for producing a holographic optical element. The method includes a step of exposing a recording material to a phase pattern which is provided by a first modulated light beam with a first phase portion. Furthermore, the method includes a step of an additional exposure of the recording material to the phase pattern, which is provided by a second modulated light beam with a second phase portion, wherein the second phase portion has a phase offset with respect to the first phase portion in order to produce a holographic optical element.