Abstract:
A device for transferring charges photogenerated in a portion of a semiconductor layer delimited by at least two parallel trenches, each trench including, lengthwise, at least a first and a second conductive regions insulated from each other and from the semiconductor layer, including the repeating of a first step of biasing of the first conductive regions to a first voltage to form a volume accumulation of holes in the area of this portion located between the first regions, while the second conductive regions are biased to a second voltage greater than the first voltage, and of a second step of biasing of the first regions to the second voltage and of the second regions to the first voltage.
Abstract:
An optical navigation device is provided for detecting movement of a pointer, such as a finger, in three dimensions. A sensor obtains images of the pointer which have been illuminated by an illumination source, and an image scaling module determines the difference in size between images acquired by the image sensor to determine the difference in height of the pointer between images.
Abstract:
A device for transferring charges photogenerated in a portion of a semiconductor layer delimited by at least two parallel trenches, each trench including, lengthwise, at least a first and a second conductive regions insulated from each other and from the semiconductor layer, including the repeating of a first step of biasing of the first conductive regions to a first voltage to form a volume accumulation of holes in the area of this portion located between the first regions, while the second conductive regions are biased to a second voltage greater than the first voltage, and of a second step of biasing of the first regions to the second voltage and of the second regions to the first voltage.
Abstract:
A motion estimation method is provided for processing successive images in an image sequence, with a motion vector being associated with each of the processed images. For a current image, motion vectors associated with images that precede the current image in the sequence are selected. Candidate motion vectors are generated from the motion vectors that are selected. A motion vector is elected from among the candidate motion vectors. Information that associates the elected motion vector with the current image is stored in memory. At least one of candidate motion vectors is an acceleration vector generated from the acceleration between first and second motion vectors averaged relative to a first and second images, with the first and second images being distinct and preceding the current image in the image sequence. A motion vector averaged relative to a given image is obtained from selected motion vectors associated with images preceding the given image.
Abstract:
An optical mouse includes an image sensor for providing image data via an analog-to-digital converter to a correlation circuit and a motion estimation circuit to provide output signals representative of motion of the mouse. The output signals may be disabled when the mouse is lifted away from the working surface. This may be achieved by high-pass filtering the signals, summing each frame in a summer to provide a single value, and comparing this to a threshold. If the filtered and summed value exceeds the threshold, this may indicate that the image contains in-focus objects, and that the mouse is on the working surface.
Abstract:
A modulator including a noise shaper receiving the input signal and providing a signal coded over one bit, a phase loop including an adder and a shift register. The adder receives the signal coded over one bit, the output of the shift register, and a constant. The input of the shift register receives the adder output. A sinusoidal shaper is coupled to the output of the shift register to provide a signal modulated in frequency by the input signal. The present invention also relates to a modulation chain including a modulator.
Abstract:
A device for generating a regulated DC voltage from a DC power supply voltage source includes a loop formed by a reference voltage generator powering an operational amplifier. The output of the operational amplifier powers the input to the reference voltage generator.
Abstract:
An optical navigation device is provided for detecting movement of a pointer, such as a finger, in three dimensions. A sensor obtains images of the pointer which have been illuminated by an illumination source, and an image scaling module determines the difference in size between images acquired by the image sensor to determine the difference in height of the pointer between images.
Abstract:
A method and apparatus for defining, from a first periodic signal, a second signal of same period, including the steps of: generating a third signal exhibiting detectable events; and synchronizing the second signal for each event.
Abstract:
Ambient light is detected by a photodiode circuit by measuring the time taken for a digital output of the photodiode circuit to change state in response to exposure of a photodiode of the photodiode circuit to that ambient light. A nominal time for state change is calculated based on photodiode circuit characteristics. Furthermore, an effective time for the photodiode circuit digital output to change state is determined in a calibration mode where the photodiode has been disconnected and a reference current is applied to the circuit. An illumination value of the detected ambient light is then calculated as a function of: the measured time, the effective time and the nominal time.