Imec

Imec Vzw

Imec Leuven

Bert Geelen

Andy Lambrechts

Klaas Tack

Geert Vanmeerbeeck

Nicolaas Tack

Paul Coene

Bart Vereecke

Eddy De Greef

Nick Spooren

Johan De Geyter

Bart Masschelein

Wilfried Verachtert

The present invention relates to a spectral sensor. The spectral sensor comprising: a light detecting element; a microlens; and an interference filter arranged between the light detecting element and the microlens, and configured to transmit light in one or more spectral bands; wherein the microlens has an effective focal length (F) exceeding a distance (D) between the microlens and the light detecting element. The microlens may be configured such that light refracted by the microlens, to be transmitted through the interference filter, converges towards a position (P) behind the light detecting element. The present invention further relates to an image sensor comprising a plurality of spectral sensors.

Spectral sensors

An imaging sensor comprises: an array of light-detecting elements, wherein each light-detecting element in the array of light-detecting elements is arranged in the imaging sensor so as to detect a respective wavelength interval, wherein the respective wavelength interval differs for different light-detecting elements; a pattern arranged on the array of light-detecting elements, wherein the pattern defines a plurality of transparent areas, each transparent area being associated with a corresponding light-detecting element in the array of light-detecting elements, wherein a size of a transparent area among the plurality of transparent areas is dependent of the corresponding light-detecting element with which the transparent area is associated.

Imaging sensor

Example embodiments relate to image sensors and imaging apparatuses. One embodiment includes an image sensor for acquiring an image of an object. The image sensor includes an array of photo-sensitive areas formed on a substrate. Each photo-sensitive area is a continuous area within the substrate and is configured to detect incident light. The image sensor also includes an array of interference filters. Each inference filter is configured to selectively transmit a wavelength band. The array of interference filters is monolithically integrated on the array of photo-sensitive areas. A plurality of the interference filers is associated with a single photo-sensitive area of the array of photo-sensitive areas. Each interference filter in the plurality of interference filters is configured to selectively transmit a unique wavelength band to the photo-sensitive area and each interference filter in the plurality of interference filters is associated with a respective portion of the single photo-sensitive area.

Image sensor and imaging apparatus having an array of interference filters

A spectral camera for producing a spectral output is disclosed. The spectral camera has an objective lens for producing an image, a mosaic of filters for passing different bands of the optical spectrum, and a sensor array arranged to detect pixels of the image at the different bands passed by the filters, wherein for each of the pixels, the sensor array has a cluster of sensor elements for detecting the different bands, and the mosaic has a corresponding cluster of filters of different bands, integrated on the sensor element so that the image can be detected simultaneously at the different bands. Further, the filters are first order Fabry-Perot filters, which can give any desired passband to give high spectral definition. Cross talk can be reduced since there is no longer a parasitic cavity.

Spectral camera with mosaic of filters for each image pixel

A spectral camera for producing a spectral output is disclosed. The spectral camera has an objective lens for producing an image, an array of mirrors, an array of filters for passing a different passband of the optical spectrum for different ones of the optical channels arranged so as to project multiple of the optical channels onto different parts of the same focal plane, and a sensor array at the focal plane to detect the filtered image copies simultaneously. By using mirrors, there may be less optical degradation and the trade off of cost with optical quality can be better. By projecting the optical channels onto different parts of the same focal plane a single sensor or coplanar multiple sensors can to be used to detect the different optical channels simultaneously which promotes simpler alignment and manufacturing.

Spectral camera with mirrors for projecting multiple adjacent image copies onto sensor array

A spectral camera for producing a spectral output is disclosed. The spectral camera has an objective lens for producing an image, an optical duplicator, an array of filters, and a sensor array arranged to detect the filtered image copies simultaneously on different parts of the sensor array. Further, a field stop defines an outline of the image copies projected on the sensor array. The filters are integrated on the sensor array, which has a planar structure without perpendicular physical barriers for preventing cross talk between each of the adjacent optical channels. The field stop enables adjacent image copies to fit together without gaps for such barriers. The integrated filters mean there is no parasitic cavity causing crosstalk between the adjacent image copies. This means there is no longer a need for barriers between adjacent projected image copies, and thus sensor area can be better utilized.

Spectral camera with integrated filters and multiple adjacent image copies projected onto sensor array

A spectral camera having an objective lens, an array of lenses for producing optical copies of segments of the image, an array of filters for the different optical channels and having an interleaved spatial pattern, and a sensor array to detect the copies of the image segments is disclosed. Further, detected segment copies of spatially adjacent optical channels have different passbands and represent overlapping segments of the image, and detected segment copies of the same passband on spatially non-adjacent optical channels represent adjacent segments of the image which fit together. Having segments of the image copied can help enable better optical quality for a given cost. Having an interleaved pattern of the filter bands with overlapping segments enables each point of the image to be sensed at different bands to obtain the spectral output for many bands simultaneously to provide better temporal resolution.

Spectral camera with overlapping segments of image copies interleaved onto sensor array

A virtual camera system comprises a plurality of physical cameras and a hardware setup miming software to create virtual viewpoints for the virtual camera system. The position of the physical cameras is constrained, where the main constraint is the overlap between the physical cameras. The present invention provides a method for creating a virtual viewpoint of a plurality of images captured by the plurality of cameras, the images comprising current frames and previous frames. The method comprises creating background frames by combining a set of previous frames; creating a plurality of foreground masks by performing segmentation on the plurality of current frames, the segmentation comprising separating foreground objects from background objects using the created background frames; extracting the foreground objects by AND-ing the plurality of current frames with the created plurality of foreground masks; rendering the foreground objects by using a three dimensional depth-box constrained viewpoint interpolation algorithm on the plurality of current frames, the three dimensional depth box being constructed for each foreground object by exploiting information from the created foreground masks and positioning information of the foreground objects; rendering a view-dependent background image by performing homographic transformations on the created background frames; and creating the virtual viewpoint by superimposing the rendered foreground objects on the rendered background frame.

Growing community of inventors

Leuven, Belgium

Bert Geelen