Abstract:
Signals representative of total photocharge integrated within respective image-sensor pixels are read out of the pixels after a first exposure interval that constitutes a first fraction of a frame interval. Signals in excess of a threshold level are read out of the pixels after an ensuing second exposure interval that constitutes a second fraction of the frame interval, leaving residual photocharge within the pixels. After a third exposure interval that constitutes a third fraction of the frame interval, signals representative of a combination of at least the residual photocharge and photocharge integrated within the pixels during the third exposure interval are read out of the pixels.
Abstract:
A control pulse is generated a first control signal line coupled to a transfer gate of a pixel to enable photocharge accumulated within a photosensitive element of the pixel to be transferred to a floating diffusion node, the first control signal line having a capacitive coupling to the floating diffusion node. A feedthrough compensation pulse is generated on a second signal line of the pixel array that also has a capacitive coupling to the floating diffusion node. The feedthrough compensation pulse is generated with a pulse polarity opposite the pulse polarity of the control pulse and is timed to coincide with the control pulse such that capacitive feedthrough of the control pulse to the floating diffusion node is reduced.
Abstract:
Signals representative of total photocharge integrated within respective image-sensor pixels are read out of the pixels after a first exposure interval that constitutes a first fraction of a frame interval. Signals in excess of a threshold level are read out of the pixels after an ensuing second exposure interval that constitutes a second fraction of the frame interval, leaving residual photocharge within the pixels. After a third exposure interval that constitutes a third fraction of the frame interval, signals representative of a combination of at least the residual photocharge and photocharge integrated within the pixels during the third exposure interval are read out of the pixels.
Abstract:
In a pixel array within an integrated-circuit image sensor, each of a plurality of pixels is evaluated to determine whether charge integrated within the pixel in response to incident light exceeds a first threshold. N-bit digital samples corresponding to the charge integrated within at least a subset of the plurality of pixels are generated, and then applied to a lookup table to retrieve respective M-bit digital values (M being less than N), wherein a stepwise range of charge integration levels represented by possible states of the M-bit digital values extends upward from a starting charge integration level that is determined based on the first threshold.
Abstract:
In an integrated-circuit image sensor having a pixel array, first and second control pulses that enable photocharge transfer from respective first and second photosensitive elements to a shared floating diffusion node are staggered in time such that capacitive feedthrough to the shared floating diffusion node from a trailing edge of the first control pulse is counteracted by capacitive feedthrough to the shared floating diffusion node from a leading edge of the second control pulse.
Abstract:
An integrated-circuit image sensor generates, as constituent reference voltages of a first voltage ramp, a first sequence of linearly related reference voltages followed by a second sequence of exponentially related reference voltages. The integrated-circuit image sensor compares the constituent reference voltages of the first voltage ramp with a first signal level representative of photocharge integrated within a pixel of the image sensor to identify a first reference voltage of the constituent reference voltages that is exceeded by the first signal level.
Abstract:
A pixel in an integrated-circuit image sensor is enabled to output, throughout a sampling interval, an analog signal having an amplitude dependent, at least in part, on photocharge integrated within a photosensitive element of the pixel. A plurality of samples of the analog signal are generated during an initial portion of the sampling interval that is shorter than a settling time for a maximum possible level of the analog signal.
Abstract:
An integrated-circuit image sensor generates, as constituent reference voltages of a first voltage ramp, a first sequence of linearly related reference voltages followed by a second sequence of exponentially related reference voltages. The integrated-circuit image sensor compares the constituent reference voltages of the first voltage ramp with a first signal level representative of photocharge integrated within a pixel of the image sensor to identify a first reference voltage of the constituent reference voltages that is exceeded by the first signal level
Abstract:
A control pulse is generated a first control signal line coupled to a transfer gate of a pixel to enable photocharge accumulated within a photosensitive element of the pixel to be transferred to a floating diffusion node, the first control signal line having a capacitive coupling to the floating diffusion node. A feedthrough compensation pulse is generated on a second signal line of the pixel array that also has a capacitive coupling to the floating diffusion node. The feedthrough compensation pulse is generated with a pulse polarity opposite the pulse polarity of the control pulse and is timed to coincide with the control pulse such that capacitive feedthrough of the control pulse to the floating diffusion node is reduced.
Abstract:
In a pixel array within an integrated-circuit image sensor, each of a plurality of pixels is evaluated to determine whether charge integrated within the pixel in response to incident light exceeds a first threshold. N-bit digital samples corresponding to the charge integrated within at least a subset of the plurality of pixels are generated, and then applied to a lookup table to retrieve respective M-bit digital values (M being less than N), wherein a stepwise range of charge integration levels represented by possible states of the M-bit digital values extends upward from a starting charge integration level that is determined based on the first threshold.