E2v Semiconductors

Teledyne E2v Semiconductors Sas

Atmel Grenoble

Pierre Fereyre

Frédéric Mayer

Frédéric Barbier

Thierry Ligozat

Bruno Diasparra

Stéphane Gesset

Vincent Prevost

Caroline Papaix

Philippe Moenne-Loccoz

Pascal Douine

Simon Caruel

Raphaël Neri

Pierre-Emmanuel Ville

Christophe Mailland

The invention concerns a TOF vision camera and proposes an electronic control circuit comprising a modulation circuit MOD for modulating the carrier clock signal, applying a camera-specific pulse position modulation function k(t) in order to output a modulation clock signal fe which is applied in the camera as a camera light source modulation signal S-LED, in order to control the emission of a series of light pulses SE and in order to synchronously control the N capture phases ST0, ST1, ST2, ST3 of the matrix image sensor CI of the camera. This modulation clock signal fe is such that the clock pulses fe have a constant pulse duration Tp, fixed by the carrier frequency fp, where Tp=½fp, and with a variable time interval Toff between two successive pulses, modulated by said modulation function k(t), said time interval being at least equal to the pulse duration, defining a modulation clock cycle ratio fe that is variable but less than or equal to 50%.

Optimized time of flight vision camera for a multi-camera environment

The subject matter of the invention is an active pixel dental radiological image sensor, with integrated X-ray occurrence detection, which uses the pixels of the matrix to detect the start of an X-ray flash, by detecting the current produced by all the photodiodes in the matrix. A switching circuit MUXthus allows, in a first phase of detecting the start of an X-ray flash, a common connection node NC to be connected that corresponds to the drain of a photodiode initialisation transistor Mat the input of a current-voltage conversion detection circuit DTX, which provides as output a signal for detecting the start of an X-ray flash when the current produced by all the photodiodes of the matrix exceeds a predetermined threshold. The switching circuit MUXis then controlled to connect the common connection node NC of the pixels to a photodiode re-initialisation voltage source, VRS. In an alternative embodiment, some pixels of the matrix can be used to detect the end of an X-ray flash using the same principle, by injecting the current produced by the photodiodes of these pixels that is collected on a different common connection node, electrically isolated from the first, with the end of flash signal corresponding to a variation in this current, which falls below a predetermined threshold. The active pixels can be of the three or more transistor type, in particular with five and more transistors.

Active pixel intraoral radiological image sensor and associated image capture method

To eliminate image defects produced by high-energy particles passing through a time delay integration image sensor, upstream detection is effected on the digital values supplied by the pixels of the same rank that have successively observed the same scene point. This detection makes it possible to ignore or to correct values from corrupted pixels in establishing the digital signal representing the luminance of an observed scene point. Detection is based on the calculation of the difference between a first digital value p(t) and a second digital value p(t) supplied by two pixels Pxand Pxthat have observed the same scene point, subtracting the second value from the first, and comparing it to a predetermined threshold k. If this difference is above the threshold, the first value is too high, the first value is ignored in the summation &#x3a3;'effected to establish the luminance of the scene point, replacing this value with the second value to which it has been compared. Alternatively it is replaced by a mean value or excluded from the calculation.

Time delay integration image capture method correcting image defects caused by cosmic particles

The invention relates to color-image sensors. To benefit both from a good luminance resolution and a color accuracy that is not excessively degraded by the sensitivity of silicon to near-infrared radiation, the invention proposes to produce a mosaic of pixels comprising colored pixels (R), (G), (B), coated with color filters, which are distributed in the matrix, with white pixels (T) not coated with color filters and which are distributed in the matrix. The colored pixels include photodiodes constructed differently from the photodiodes of the white pixels, the different construction being such that the photodiodes of the colored pixels have a lower sensitivity to infrared radiation than the photodiodes of the white pixels.

Colour image sensor with white pixels and colour pixels

The invention relates to the production of images associating with each point of the image a depth, i.e. a distance between the observed point and the camera that produced the image. A light source emits N trains of light pulses. For each train of rank I=1 to N, charge is integrated in a short time slot of length Tthat starts with a temporal offset trelative to the pulse, this temporal offset representing a journey time of the light pulse between the light source and the sensor after reflection from a point placed a distance dfrom the sensor. The temporal offset tis the same for all the light pulses of the ipulse train but the temporal offsets tof the N trains are different from one another in order to correspond to various distances relative to the sensor. The charge photogenerated by the pulses of a given train is accumulated; then the accumulated charge is read in order to produce an image of rank i representing the pixels located at the distance d. The observation of a scene comprises producing N different images by virtue of which it is possible to associate a distance with each pixel.

Method for producing images with depth information and image sensor

This description relates to active-pixel image sensors. Each pixel includes, at the surface of a semiconductor active layer, a photodiode region, a charge storage node and a transfer structure for transferring charges from the photodiode to the storage node after a charge integration time for charges generated by the light in the photodiode. The transfer structure includes a first transfer gate adjacent to the photodiode, a second transfer gate adjacent to the storage node, and an electron-multiplication amplifying structure located between the first and second transfer gates. The amplifying structure includes two separate accelerating gates and an intermediate diode region at a fixed surface potential, located between the two accelerating gates. A succession of alternating high and low potentials is applied to the accelerating gates while the charges are in transit in the transfer structure, before they are transferred to the storage node.

Electron-multiplication image sensor

A image sensor includes active pixels for gathering images at very high and very low luminance level. Each pixel includes at least one photodiode, a charge storage node, an electron multiplication amplification structure, a unit for transferring electrons from the photodiode to the structure, a unit for transferring electrons from the amplification structure to the storage node after multiplication, a transistor for reinitializing the potential of the storage node. The pixels are read by a reading circuit which samples the potential of the charge storage node after reinitialization and after transfer of the electrons into the storage node and which provides a corresponding illumination measurement. The sensor furthermore includes a unit for carrying out the integration of charge in two different durations in the course of one and the same frame, and for giving the amplification structure multiplication factors different to the charge integrated in the course of these durations.

Image sensor with very high dynamic range

The invention relates to image sensors produced with CMOS technology, whose individual pixels, arranged in an array of rows and columns, each consist of a photodiode (PD) associated with a charge storage region (N) which receives the photogenerated charge before a charge readout phase. To eliminate the risk of introducing kTC-type noise into the signal, during the reset of the storage zone (N) at the end of a readout cycle, the invention proposes that the storage zone be divided into two parts one of which (N), adjacent to the reset gate (G), is covered by a diffused region (P) of the same type of conductivity as the substrate in which the photodiode is formed, this region being brought to the fixed potential of the substrate, and the other (N) of which is not covered by such a region and is not adjacent to the reset gate.

Image sensor having four-transistor or five-transistor pixels with reset noise reduction

The invention relates to image sensors produced on a thinned silicon substrate. To limit the optical crosstalk between adjacent filters and, notably filters of different colors, the invention proposes positioning, between the adjacent filters of different colors (FR, FB, FV), a wall () of a material tending to reflect the light so that the light arriving obliquely on a determined filter corresponding to a first pixel does not tend to pass toward an adjacent filter or toward a photosensitive zone corresponding to an adjacent pixel but is returned by the wall to the first filter or the photosensitive zone corresponding to the first pixel. The wall is preferably made of a material with a high reflection coefficient such as aluminium and it is sunk depthwise into the thinned semiconductor layer (), preferably in pdiffusions formed in the layer if it is of p-type.

Color image sensor with improved optical crosstalk

The invention proposes an image sensor comprising a picture capture matrix having N rows and K columns of image dots, a read register at the free end of the K columns. In order to improve the read speed of the matrix, the invention proposes that the horizontal transfer into the read register be continued even while the vertical signals for shifting from one row to the other are operative, without however continuing the horizontal transfer while the transfer gate between columns and horizontal register is open. The unloading time of the horizontal read register therefore overlaps the time reserved for each vertical transfer step, instead of these times being added together. The gain in time, being repeated for each row, will be all the more significant the higher the number of rows. Means are provided for limiting the effect of the column transfer switching operations on the reading of the charges at the output of the read register.

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Voreppe, France

Pierre Fereyre