Abstract:
An imaging element includes a photosensor and a transfer transistor to transfer electrical charges from the photosensor to a charge accumulation node. A selector is configured to receive at least two logic selection signals and to supply an activation signal, which is a function of the selection signals, to a control terminal of the transfer transistor. The selector is configured to receive at least two selection signals, each having a positive voltage when it is at a logic value 1 and a negative voltage when it is a logic value 0, and to supply the activation signal having a negative voltage when the imaging element is not selected.
Abstract:
A method for controlling a pixel may include first and second photosites, each having a photodiode and a charge-transfer transistor, a read node, and an electronic read element, all of which are common to all the photosites. The method may include an accumulation of photogenerated charges in the photodiode of the first photosite during a first period, an accumulation of photogenerated charges in the photodiode of the second photosite during a second period shorter than the first period, a selection of the signal corresponding to the quantity of charges accumulated in the photodiode of a photosite having the highest unsaturated intensity or else a saturation signal, and a digitization of the selected signal.
Abstract:
A method of reading voltages from an image sensor having an array of pixels, each pixel having at least one photodiode connectable to a storage node, the method having: controlling each pixel in a row of pixels to transfer charge accumulated in the photodiode above a first threshold to the storage node at the start and end of a first integration period and reading a first voltage at the storage node of each pixel in the row at the end of the first integration period; controlling of the pixels in the row to transfer charge accumulated in the photodiode above a second threshold to the storage node at the start and end of a second integration period longer than the first integration period, and reading a second voltage value at the storage node of each pixel in the row at the end of the second integration period; controlling each pixel in a row of pixels to transfer charge accumulated in the photodiode to the storage node at the end of a third integration period longer than the first and second integration periods; comparing for each pixel in the row, the first voltage values with a reference voltage; and based on the comparison, for each pixel in the row, performing one of: determining a pixel output value based on the first and/or second voltage values; and reading a third voltage value at the end of the third integration period, and determining a pixel output value based on the second and/or third voltage values.
Abstract:
A device for controlling an image sensor including at least one photosensitive cell including a photodiode capable of discharging into a sense node via a first MOS transistor, the sense node being connected to the gate of a second MOS transistor having its source connected to a processing system. The device includes a bias circuit capable of increasing the voltage of the source during the discharge of the photodiode into the sense node.
Abstract:
An imaging element includes a photosensor and a transfer transistor to transfer electrical charges from the photosensor to a charge accumulation node. A selector is configured to receive at least two logic selection signals and to supply an activation signal, which is a function of the selection signals, to a control terminal of the transfer transistor. The selector is configured to receive at least two selection signals, each having a positive voltage when it is at a logic value 1 and a negative voltage when it is a logic value 0, and to supply the activation signal having a negative voltage when the imaging element is not selected.
Abstract:
A method for controlling a pixel may include first and second photosites, each having a photodiode and a charge-transfer transistor, a read node, and an electronic read element, all of which are common to all the photosites. The method may include an accumulation of photogenerated charges in the photodiode of the first photosite during a first period, an accumulation of photogenerated charges in the photodiode of the second photosite during a second period shorter than the first period, a selection of the signal corresponding to the quantity of charges accumulated in the photodiode of a photosite having the highest unsaturated intensity or else a saturation signal, and a digitization of the selected signal.
Abstract:
An image sensor formed of an array of pixels, each pixel including a photodiode coupled between a first reference voltage and a first switch, the first switch being operable to connect the photodiode to a first node; a capacitor arranged to store a charge accumulated by the photodiode, the capacitor being coupled between a second reference voltage and a second node; a second switch coupled between the first and second nodes, the second switch being operable to connect the capacitor to the first node; and read circuitry coupled for reading the voltage at the second node.
Abstract:
A method of reading voltages from an image sensor having an array of pixels, each pixel Having at least one photodiode connectable to a storage node, the method including: controlling each pixel in a row of pixels to store and output a first voltage value at a first instance, a second voltage value at a second instance, and a third voltage value at a third instance, the first, second and third voltage values being representative of charge accumulated by the photodiodes during an integration phase; comparing the first voltage value from each pixel with a reference threshold; sampling for each pixel, based on the comparison, one of the second and third voltage values: and generating an output pixel value based on the sampled one of the second and third voltage values