Abstract: The invention relates to computation of optical flow using event-based vision sensors.

Abstract: The invention relates to computation of optical flow using event-based vision sensors.

Abstract: The present invention relates to a method for detecting and reconstructing a surface illuminated with spatially structured light such that the light illuminates an area of the surface from which the light is reflected back. The light includes a temporarily varying intensity in the form of successive light modulation patterns. The back-reflected light is detected by an optical sensor including a plurality of pixels. A pixel coordinate is associated to each pixel and each pixel generated a photocurrent proportional to the intensity of the light impinging on a respective pixel, computes a signal related to a photocurrent, and each pixel outputs an address-event merely when a respective signal due to the light impinging on the respective pixel increases by an amount larger than a first threshold or decreases by an amount larger than a second threshold since a last address-event from the respective pixel.

Abstract: The present invention relates to a method for tracking a position of at least one keypoint in an image of an object moving relative to an optical sensor, wherein light reflected from the object (12) is detected so as to generate an image of the object, and wherein a position of at least one keypoint (Kj) in said image is detected and updated using temporal contrast events (Ev) of the optical sensor. The invention also relates to a corresponding computer program and device.

Abstract: The present invention relates to a method for detecting and reconstructing a surface illuminated with spatially structured light such that the light illuminates an area of the surface from which the light is reflected back. The light includes a temporarily varying intensity in the form of successive light modulation patterns. The back-reflected light is detected by an optical sensor including a plurality of pixels. A pixel coordinate is associated to each pixel and each pixel generated a photocurrent proportional to the intensity of the light impinging on a respective pixel, computes a signal related to a photocurrent, and each pixel outputs an address-event merely when a respective signal due to the light impinging on the respective pixel increases by an amount larger than a first threshold or decreases by an amount larger than a second threshold since a last address-event from the respective pixel.

Abstract: The present invention relates to a method for tracking a position of at least one keypoint in an image of an object moving relative to an optical sensor, wherein light reflected from the object (12) is detected so as to generate an image of the object, and wherein a position of at least one keypoint (Kj) in said image is detected and updated using temporal contrast events (Ev) of the optical sensor. The invention also relates to a corresponding computer program and device.

Abstract: The invention relates to a photoarray (1), comprising: a plurality of cells (10), wherein each of said cells (10) comprises a means (20)that is configured to generate a photocurrent (I) being proportional to the intensity (L) of the light impinging on the respective cell (10), and wherein each of said cells (10) comprises a change detection circuit (100) connected to the respective means (20) for generating the photocurrent (I), which change detection circuit (100) is configured to generate an output signal merely in case a change event occurs at which said intensity (L) changes by a threshold amount (T, T?) since the preceding change event from the respective cell (10). According to the invention said means (20) for generating said photocurrent (I) is additionally also used to estimate the magnitude of the said photocurrent (I) being a measure of the brightness of the light at the respective cell (10).

Abstract: The present invention relates to a method for detecting and reconstructing a surface illuminated with spatially structured light such that the light illuminates an area of the surface from which the light is reflected back. The light includes a temporarily varying intensity in the form of successive light modulation patterns. The back-reflected light is detected by an optical sensor including a plurality of pixels. A pixel coordinate is associated to each pixel and each pixel generated a photocurrent proportional to the intensity of the light impinging on a respective pixel, computes a signal related to a photocurrent, and each pixel outputs an address-event merely when a respective signal due to the light impinging on the respective pixel increases by an amount larger than a first threshold or decreases by an amount larger than a second threshold since a last address-event from the respective pixel.

Abstract: The invention relates to a photoarray (1), comprising: a plurality of cells (10), wherein each of said cells (10) comprises a means (20)that is configured to generate a photocurrent (I) being proportional to the intensity (L) of the light impinging on the respective cell (10), and wherein each of said cells (10) comprises a change detection circuit (100) connected to the respective means (20) for generating the photocurrent (I), which change detection circuit (100) is configured to generate an output signal merely in case a change event occurs at which said intensity (L) changes by a threshold amount (T, T?) since the preceding change event from the respective cell (10). According to the invention said means (20) for generating said photocurrent (I) is additionally also used to estimate the magnitude of the said photocurrent (I) being a measure of the brightness of the light at the respective cell (10).

Abstract: A photosensitive device with a photodiode and an amplifier is disclosed. The diode is in series with a feedback transistor which forces the voltage derived from the photocurrent to be a logarithmic function of the light intensity. A current mirror is provided which controls the bias current to the amplifier to be proportional to the photocurrent. This arrangement ensures that the amplifier, just as the voltage derived from the photocurrent, becomes faster with increasing light intensity and therefore prevents an unnecessarily high power consumption at low light intensities.

Abstract: A photosensitive device with a photodiode and an amplifier is disclosed. The diode is in series with a feedback transistor which forces the voltage derived from the photocurrent to be a logarithmic function of the light intensity. A current mirror is provided which controls the bias current to the amplifier to be proportional to the photocurrent. This arrangement ensures that the amplifier, just as the voltage derived from the photocurrent, becomes faster with increasing light intensity and therefore prevents an unnecessarily high power consumption at low light intensities.

Abstract: A device for controlling a physical system, such as a flow of pedestrians, in an extended area is suggested. In comprises a plurality of identical cell units with preferably hexagonal shape. The cell units are assembled in tile-like manner to form a floor. Each cell unit is equipped with a weight sensor, lamps of different colors, and optical communication ports as well as power connectors for connecting it to its neighboring cells. The cell units can be programmed to generate signals that control the physical system, such as signs understood by the pedestrians. Due to its modularity and simple design, the device is easy to install and maintain.

Abstract: A sense amplifier comprises an input node and an output node. An input transistor has a gate connected to the input node, a source connected to a first supply voltage rail, and a drain. A cascode transistor has a gate connected to a cascode node, a source connected to the drain of the input transistor, and a drain connected to the output node. A load transistor has a gate connected to a bias node, a drain connected to the output node, and a source connected to a second supply voltage rail. The gates of the cascode transistor and the load transistor are biased such that the input transistor and the cascode transistor are operated near their threshold and the load transistor is operated above threshold. In a presently preferred embodiment of the present invention, the input transistor and the cascode transistor of the sense amplifier are wide and short, such that they operate in below threshold, whereas the load transistor is made long and relatively narrow, so that it operates above threshold.

Abstract: A sense amplifier comprises an input node and an output node. An input transistor has a gate connected to the input node, a source connected to a first supply voltage rail, and a drain. A cascode transistor has a gate connected to a cascode node, a source connected to the drain of the input transistor, and a drain connected to the output node. A load transistor has a gate connected to a bias node, a drain connected to the output node, and a source connected to a second supply voltage rail. The gates of the cascode transistor and the load transistor are biased such that the input transistor and the cascode transistor are operated near their threshold and the load transistor is operated above threshold. In a presently preferred embodiment of the present invention, the input transistor and the cascode transistor of the sense amplifier are wide and short, such that they operate in below threshold, whereas the load transistor is made long and relatively narrow, so that it operates above threshold.

Abstract: A correlated double sampling circuit comprising an input node comprising a first plate of input capacitor and an output node. A first plate of a feedback capacitor is connected to the output node and a second plate of the feedback capacitor is connected to a second plate of the input capacitor. An input transistor has a gate connected to the second plate of the input capacitor, a source connected to a first supply voltage rail, and a drain connected to the output node. A load transistor has a gate connected to a bias node, a drain connected to the output node, and a source connected to a second supply voltage rail. A reset transistor is connected between output node and the second plate of the input capacitor, and has a gate connected to a reset signal line.

Abstract: An adaptive photoreceptor semiconductor circuit for long-time-constant continuous learning having a low offset and insensitivity to light includes a photodiode in series with an MOS feedback transistor connected across a potential difference. An inverting amplifier comprises a first MOS amplifier transistor having its gate connected to a source of bias voltage potential in series with an cascode transistor having its gate connected to a source of cascode voltage potential and a second MOS amplifier transistor having its gate connected to the common connection between the photodiode and the MOS feedback transistor. An output node comprises the connection between the first MOS amplifier transistor and the cascode transistor. A light insensitive adaptive element has a driven node connected to the output node and an isolated node connected to the gate of the MOS feedback transistor. A capacitive voltage divider is connected between a first power supply rail, the adaptive element, and the output node.

Abstract: A first and a second MOS transistor of the same conductivity type are connected in series between a load and a fixed voltage source. The gates of the first and second MOS transistors are connected to sources of input voltage which are of a magnitude smaller than the threshold voltages of the two MOS transistors. The first MOS transistor located next to the load is kept in saturation. A related circuit includes a first and a second MOS transistor of the same conductivity type are connected in series between a load and a fixed voltage source. The first MOS transistor located next to the load is kept in saturation. The gates of the first and second MOS transistors are connected to the gates of third and fourth diode-connected MOS transistors of the same conductivity type as the first and second MOS transistors. The third MOS transistor is connected between a first input current node and a fixed voltage source. The fourth MOS transistor is connected between a second input current node and a fixed voltage source.

Abstract: A first and a second MOS transistor of the same conductivity type are connected in series between a load and a fixed voltage source. The gates of the first and second MOS transistors are connected to sources of input voltage which are of a magnitude smaller than the threshold voltages of the two MOS transistors. The first MOS transistor located next to the load is kept in saturation. A related circuit includes a first and a second MOS transistor of the same conductivity type are connected in series between a load and a fixed voltage source. The first MOS transistor located next to the load is kept in saturation. The gates of the first and second MOS transistors are connected to the gates of third and fourth diode-connected MOS transistors of the same conductivity type as the first and second MOS transistors. The third MOS transistor is connected between a first input current node and fixed voltage source. The fourth MOS transistor is connected between a second input current node and a fixed voltage source.