Abstract: A method for obtaining light field data of a scene from a sequence of images of the scene, each image being captured at a different viewpoint using a non-light-field image capture device is described. The method includes obtaining a reference image of the scene at a reference viewpoint, an interest area of the scene being included in the reference image and a reference position (x0,y0) being associated with the interest area in a reference local coordinate system of the capture device.

Abstract: The disclosure relates to a visual data processing device and a visual data processing method. The device is used for displaying visual data for a terminal. The device comprises: a module configured to obtaining a three-dimensional position of the terminal with respect to a reference point on a user of the terminal; a module configured to determining, in relation to said three-dimensional position of the terminal, a subset of three-dimensional visual data to be displayed from the point of view of the reference point, in function of a set of available visual data; a module configured to modifying said subset of three-dimensional visual data to be displayed, delivering modified visual data; a module configured to displaying, on a displaying module of the terminal, the modified visual data.

Abstract: An optical see-through glass type display device comprises: an optical unit having a front correcting surface and a rear correcting surface; an image projector projecting a virtual image; and an image sensor for capturing an ambient scene image. The optical unit is configured to guide light of the ambient scene image coming through the front correcting surface to the image sensor and to guide light of the virtual image so that the light of the virtual image outgoes through the rear correcting surface. A first optical compensation element is located between the optical unit and the image sensor and a second optical compensation element is located between the image projector and the optical unit. The device further comprises a processing module configured to analyze the ambient scene image captured by the image sensor.

Abstract: The multi-image capture system comprises an imaging lens, a beamsplitter directing a first portion of light on an array of micro-imaging elements and a first photodetector array divided into a plurality of macropixels providing a set of depth images, and another portion of light on a second photodetector array 6 providing a main image with a resolution being higher than the resolution of each basic depth image. According to the invention, the resolution of the depth images is increased by using the image data of the main image.

Abstract: A Fresnel lens comprises at least one first prism and one second prism. Each prism has a first side and a second side which forms with a main axis an angle greater than that formed by the first side and the main axis. Conventionally, the second side of the first prism collimates the light received from a light source in line with the main axis. In order to improve the optical effectiveness, the second side of the second prism transmits the light received from the source in a first direction slightly different from the main axis.

Abstract: The multi-image capture system comprises an imaging lens, a beamsplitter directing a first portion of light on an array of micro-imaging elements and a first photodetector array divided into a plurality of macropixels providing a set of depth images, and another portion of light on a second photodetector array 6 providing a main image with a resolution being higher than the resolution of each basic depth image. According to the invention, the resolution of the depth images is increased by using the image data of the main image.

Abstract: A Fresnel lens comprises at least one first prism and one second prism. Each prism has a first side and a second side which forms with a main axis an angle greater than that formed by the first side and the main axis. Conventionally, the second side of the first prism collimates the light received from a light source in line with the main axis. In order to improve the optical effectiveness, the second side of the second prism transmits the light received from the source in a first direction slightly different from the main axis.

Abstract: An optical plate, in particular in a screen for projection display device, comprises, on a first side, optical elements designed to bend rays received from a light source into a beam of rays in a first direction in a plane containing a main axis. The second side is produced in such a way as to bend the beam in a second direction that is different from the first direction, preferably in line with the main axis.

Abstract: A sequential illumination system for a visual display unit has a light source emitting a polychromatic light beam towards the visual display unit within a wavelength range having at least three primary colors, and a color wheel provided with at least three transmissive or reflective segments for transmitting the light beam along an optical path in such a way that they successively cut the direction of propagation of the beam. The colour segments are distributed on the wheel in such an order that the differences of energies perceived by the visual organ of a standard observer (visual stimuli), are as equivalent as possible during the intersegment transitions, when the segments pass along the optical path of the beam. The illumination system can be used for movie overhead projection devices.

Abstract: The invention relates to a Fresnel lens. Each refractive structure of the lens is bounded by two surfaces, the second surface making a second angle with the normal to the plane of incidence. At least two zones of refractive structures are provided in which the second angle is equal to the entrance angle of a beam. Each first surface refracts the light along a direction parallel or not parallel to the axis of the lens depending on the zone. The invention also relates to a system comprising a folding mirror and a Fresnel lens, in which system the second angle is equal to the entrance angle of a parasitic ray obtained by reflection on the Fresnel lens and then on the mirror. The invention also relates to a corresponding back projection screen and a corresponding back projection unit.

Abstract: The invention concerns a display apparatus with an imager illuminated by an illumination system and with an imaging system projecting an image on a viewing screen, wherein the brightness of the image on the imager has a variation over a given direction, and wherein the illumination system has light controlling elements for controlling the light distribution over the given direction.

Abstract: The invention relates to a sequential illumination system for a visual display unit comprising a light source emitting a polychromatic light beam towards said visual display unit within a wavelength range comprising at least three primary colours, and a colour wheel provided with at least three transmissive or reflective segments for transmitting said light beam along an optical path in such a way they successively cut the direction of propagation of said beam. The colour segments are distributed on the said wheel in such an order that the differences of energies perceived by the visual organ of a standard observer (visual stimuli), are as equivalent as possible during the intersegment transitions, when the segments pass along the optical path of the beam. Said invention can be used for movie projection and overhead projection devices.

Abstract: The invention relates to a Fresnel lens. Each refractive structure of the lens is bounded by two surfaces, the second surface making a second angle with the normal to the plane of incidence. At least two zones of refractive structures are provided in which the second angle is equal to the entrance angle of a beam. Each first surface refracts the light along a direction parallel or not parallel to the axis of the lens depending on the zone. The invention also relates to a system comprising a folding mirror and a Fresnel lens, in which system the second angle is equal to the entrance angle of a parasitic ray obtained by reflection on the Fresnel lens and then on the mirror. The invention also relates to a corresponding back projection screen and a corresponding back projection unit.

Abstract: System for the sequential illumination of an imager comprising a color wheel comprising at least two coplanar subsets of three colored segments The color wheel comprises at least one subset of segments of primary colors 61R, 61G and 61B, and one subset of segments of composite colors. The subset of segments of composite colors comprises a segment transmitting in the ranges of wavelengths corresponding to red and to green, a segment transmitting in the ranges of wavelengths corresponding to green and to blue, and a segment transmitting in the ranges of wavelengths corresponding to red and to blue. Thus, the luminosity of image display systems is improved, and the phenomenon of “color break-up” is appreciably reduced. Corresponding projection appliance.

Abstract: The invention concerns a display apparatus with an imager illuminated by an illumination system and with an imaging system projecting an image on a viewing screen, wherein the brightness of the image on the imager has a variation over a given direction, and wherein the illumination system has means for controlling the light distribution over the given direction.