System and method for acquiring visible and near infrared images by means of a single matrix sensor

An image acquisition system, comprising:

• a matrix sensor comprising a two-dimensional arrangement of a plurality of pixels, each of said pixels being adapted to generate an electrical signal representative of light intensity at a point of an optical image of a scene;
• and
• a signal processing circuit configured to process the electrical signal generated by each of said pixels to generate digital images of said scene;
• wherein the plurality of pixels comprises colored pixels of first, second, and third types and panchromatic pixels;
• wherein the colored pixels of the first type are sensitive to visible light in a first spectral band;
• wherein the colored pixels of the second type are sensitive to visible light in a second spectral band different from the first spectral band;
• and
• wherein the colored pixels of the third type are sensitive to visible light in a third spectral band different from the first and second spectral bands,
• wherein a combination of the first, second, and third spectral bands reconstitutes all visible spectrum;
• wherein the panchromatic pixels are sensitive to the visible spectrum and near-infrared;
• and
• wherein said signal processing circuit is further configured to:
• reconstruct a first set of monochromatic images from the electrical signals generated by the colored pixels of the first, second, and third types;
• reconstruct a panchromatic image from the electrical signals generated by the panchromatic pixels;
• reconstruct a second set of monochromatic images from the electrical signals generated by the colored pixels, and from said panchromatic image;
• reconstruct a color image by application of a first colorimetry matrix to the monochromatic images of the first set and to said panchromatic image;
• reconstruct at least one image in the near-infrared by application of a second colorimetry matrix at least to the monochromatic images of the second set and to said panchromatic image;
• and
• supply as output said color image and said at least one image in the near-infrared.