Thomson Licensing

Interdigital Ce Patent Holdings

Interdigital Vc Holdings, Inc.

Thomsom Licensing

Arno Schubert

Valter Drazic

Laurent Blonde

Nicolas Le Scouarnec

Pascal Benoit

Guillaume Boisson

Olivier Bureller

Didier Doyen

Eugene Murphy O'Donnell

Benoit Vandame

Khaled Sarayeddine

Paul Kerbiriou

Mozhdeh Seifi

Julien Thollot

Thierry Borel

Oksana Shramkova

Remi Gendrot

Laurent BlondÉ

It is proposed an optical device for delivering a polychromatic image to an eye box being an area positioned in front of an eye of a user wearing said optical device. The optical device is remarkable in that it comprises: • a light-engine for delivering said polychromatic image, said light engine being able to generate n different monochromatic light image beams [C, . . . , C, . . . , C, whom combination corresponds to said polychromatic image, each monochromatic light image Cbeing associated with a wavelength Ay, and wherein A>Afor all the i E [1, n], and wherein the monochromatic light image beams Cis in a transverse electric mode if j is odd, and the monochromatic light image beams Cis in a transverse magnetic mode if j is even; • n-waveguide elements () that are stack on each other, n being an integer greater or equal to three, each waveguide element, except the one closer to the eye of a user, comprising a diffraction grating that can deviate only one of said n monochromatic light image in the waveguide element by total internal reflection, a first output that delivers deviated light toward said eye box, and a second output that delivers non-deviated light by a waveguide element to a subsequent waveguide element, wherein said second output comprising an achromatic half-wave plate (506, 507), and wherein the waveguide element that is closer to the eye of the user comprises also a diffraction grating that can deviate only one of said n monochromatic light image in the waveguide element by total internal reflection, and an output that delivers deviated light toward said eye box, wherein each diffraction grating of said optical device is associated with a different wavelength, and, wherein the arrangement order of said n-waveguide is done according to the wavelength value, from the smallest to the highest, the smallest waveguide element being positioned closer to the light engine.

Optical device comprising a multi-layers waveguides

A system and method for generating high resolution images using a plenoptic camera, is provided. In one embodiment, the comprises capturing a first set of images in a first unexcited state of operation by using a birefringent medium disposed between a main lens and an array of lenses having a plurality of apertures. Each pixel of the first set of images is then mapped to a first set of apertures. The first unexcited state is then caused to become a second excited state by applying a voltage across said birefringent medium. A second set of images are captured in the second excited state and a second set of pixels of the second image is mapped to a second set of apertures. A value is calculated for each first and second set of images and the value associated with said first set of images is subtracted from at least two times the value calculated from said second set of image.

Plenoptic sub aperture view shuffling with improved resolution

There are several types of plenoptic devices having their proprietary file format. At present there is no standard supporting the acquisition and transmission of multidimensional information for an exhaustive over-view of the different parameters upon which a light-field depends. As such acquired light-field data for different cameras have a diversity of formats. The notion of pixel beam, which represents a volume occupied by a set of rays of light in an object space of an optical system of a camera is thus introduced. The method according to the invention enables to provide data representative of a collection of pixel beams describing a first optical system that is agnostic since these data are obtained by imaging the collection of pixel beams through a second optical system. Such data representative of a collection of pixel beams enable the generation of parametrized output images from which post-processing.

Apparatus and a method for generating data representative of a pixel beam

A system and method for generating multiple images with rich color acquisition using a plenoptic camera having a main lens disposed in front of a micro array of lenses, a mosaic color filter array and an image sensor, characterized in that it comprises: capturing a first set of images using an ordinary state of an electrically controllable birefringent medium being disposed between said main lens and said micro array of lenses, said ordinary state providing an ordinary ray to each pixel; capturing a second set of images using an extraordinary state of said electrically controllable birefringent medium, said extraordinary state splitting the light from said main lens into an ordinary ray and a extraordinary ray respectively impinging on two adjacent pixels of different colors, said extraordinary ray being shifted by distance of one pixel on said image sensor; performing a weighted subtraction of information about said second set of images from information about said first set of images; and generating a final set of images with rich color information from said weighted subtraction and said first set of images.

Plenoptic sub aperture view shuffling for a richer color sampling

There are several types of plenoptic devices and camera arrays available on the market, and all these light field acquisition devices have their proprietary file format. However, there is no standard supporting the acquisition and transmission of multi-dimensional information. It is interesting to obtain information related to a correspondence between pixels of a sensor of said optical acquisition system and an object space of said optical acquisition system. Indeed, knowing which portion of the object space of an optical acquisition system a pixel belonging to the sensor of said optical acquisition system is sensing enables the improvement of signal processing operations. The notion of pixel beam, which represents a volume occupied by a set of rays of light in an object space of an optical system of a camera is thus introduce.

Apparatus and a method for generating data representing a pixel beam

In one embodiment, it is proposed a method for encoding a light field content. The method is remarkable in that it comprises: &#x2014;obtaining, for a set of light rays () associated with said light field content, four coordinates per light ray from a two planes parametrization () of said light field content; &#x2014;obtaining (), for each light ray from said set, two coordinates from said four coordinates, corresponding to a projection of said light rays from said set onto a plane (, P) perpendicular to two planes used in said two planes parametrization, defining points in a first 2D ray diagram (&#x3a0;(&#x3c7;, &#x3c7;), &#x3a0;(&#x3c7;, &#x3c7;)); &#x2014;applying () a discrete Radon transform on said first 2D ray diagram (&#x3a0;(&#x3c7;, &#x3c7;), &#x3a0;(&#x3c7;, &#x3c7;)) that delivers lines of interest in said first 2D ray diagram; &#x2014;encoding () said lines of interest into encoded lines of interest; and&#x2014;storing () said encoded lines of interest.

Method for encoding a light field content

A system and method for generating high resolution images using a plenoptic camera having a main lens in front of an array of microlenses and an image sensor, characterized in that it comprises: capturing a first set of images in a first unexcited state of operation by using a birefringent medium disposed between a said main lens and an said array of microlenses, said unexcited state of said birefringent medium providing an ordinary ray to each pixel; causing said first unexcited state to become a second excited state by applying a voltage across said birefringent medium; capturing a second set of images in said second excited state, said excited state of said birefringent medium splitting the light from said main lens into an ordinary ray and an extraordinary ray, said extraordinary ray being shifted by a distance of one half-pixel from the ordinary ray on said image sensor; subtracting pixel value associated with said first set of images from at least two times the pixel value associated with said second set of images, and generating a final set of images with high resolution from said subtraction and said first set of images.

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 (x,y) being associated with the interest area in a reference local coordinate system of the capture device. For a current image of the scene at a current viewpoint, the method identifies the interest area of the scene in the current image, determines, in the reference local coordinate system, a current position (x,y) of the interest area identified in the current image, compares the current position with the reference position and provides a capture guidance indicator adapted to guide in relative positioning of the capture device towards the interest area, as a function of results of the comparison between the current position and the reference position.

Method for obtaining light-field data using a non-light-field imaging device, corresponding device, computer program product and non-transitory computer-readable carrier medium

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.

Optical see-through glass type display device and corresponding optical unit

There are several types of plenoptic devices and camera arrays available on the market, and all these light field acquisition devices have their proprietary file format. However, there is no standard supporting the acquisition and transmission of multi-dimensional information. It is interesting to obtain information related to a correspondence between pixels of a sensor of said optical acquisition system and an object space of said optical acquisition system. Indeed, knowing which portion of the object space of an optical acquisition system a pixel belonging to the sensor of said optical acquisition system is sensing enables the improvement of signal processing operations. The notion of pixel beam, which represents a volume occupied by a set of rays of light in an object space of an optical system of a camera along with a compact format for storing such information is thus introduce.

Method and an apparatus for generating data representative of a light field

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 arrayproviding 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.

Multi-image capture system with improved depth image resolution

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.

Fresnel lens and projection display device using one such lens

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.

Sequential colour illumination system, method for producing a colour wheel for said system and a colour segment device

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.

Fresnel lens, backprojection screen, and corresponding backprojection system and unit

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.

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Chevaigne, France

Arno Schubert