Abstract: Techniques are provided for x-ray image data monitoring and signaling for patient safety. A methodology implementing the techniques according to an embodiment includes integrating energy associated with a received x-ray pulse at an array of pixels. The method also includes multiplexing a readout of the integrated energy from the array of pixels, as analog signals, into channels, and performing analog to digital conversion of the analog signals of the channels into digital signals. The method further includes generating an error indicator in response to determining that a calculated mean of the digital signals is either greater than an upper threshold value associated with saturation or less than a lower threshold value associated with underexposure. The method further includes transmitting the error indicator over a Universal Serial Bus, to an imaging system, to terminate transmission of further x-ray pulses.

Abstract: Examples include column readout amplifiers and image sensors including same. In one example, a column readout amplifier includes a signal amplifier having an amplifier output and first and second amplifier inputs, a filter capacitor having first and second terminals, the second terminal connected to a ground terminal, a buffer amplifier having a buffer amplifier input and a buffer amplifier output, a switching network configured to switchably connect the amplifier output to the buffer amplifier input and the buffer amplifier output to the first terminal of the filter capacitor during a first time period, and to switchably connect the amplifier output directly to the first terminal of the filter capacitor during a second time period, and a low-pass filter connected in a feedback path of the signal amplifier between the amplifier output and the first amplifier input, the low-pass filter including a series resistor and a capacitor.

Abstract: Examples include column readout amplifiers and image sensors including same. In one example, a column readout amplifier includes a signal amplifier having an amplifier output and first and second amplifier inputs, a filter capacitor having first and second terminals, the second terminal connected to a ground terminal, a buffer amplifier having a buffer amplifier input and a buffer amplifier output, a switching network configured to switchably connect the amplifier output to the buffer amplifier input and the buffer amplifier output to the first terminal of the filter capacitor during a first time period, and to switchably connect the amplifier output directly to the first terminal of the filter capacitor during a second time period, and a low-pass filter connected in a feedback path of the signal amplifier between the amplifier output and the first amplifier input, the low-pass filter including a series resistor and a capacitor.

Abstract: Examples include an image sensor comprising a pixel array having at least one column of addressable pixel sensors, and a column amplifier coupled to the at least one column of addressable pixel sensors, the column amplifier comprising a transistor bank including a plurality of transistors, and mode select circuitry coupled to the transistor bank and configured to establish one or more connections among the plurality of transistors to configure the column amplifier to operate in one of a differential mode of operation and a single-ended mode of operation.

Abstract: Techniques are provided for x-ray sensing for intraoral tomography. A methodology implementing the techniques according to an embodiment includes detecting an x-ray pulse based on energy received at one or more pixels of a pixel array. The method also includes integrating the energy received at each of the pixels of the array of pixels, in response to the detection, wherein the energy received at each of the pixels is associated with the x-ray pulse. The method further includes multiplexing readouts of analog signals from the array of pixels into two or more parallel channels. The method further includes simultaneously converting (or otherwise in parallel) the analog signals of each of the channels into digital signals and storing the digital signals in memory as frames of data. The method may further include, for example, transmitting the frames of data from the memory, over a Universal Serial Bus, to an imaging system.

Abstract: Techniques are provided for x-ray sensing for intraoral tomography. A methodology implementing the techniques according to an embodiment includes detecting an x-ray pulse based on energy received at one or more pixels of a pixel array. The method also includes integrating the energy received at each of the pixels of the array of pixels, in response to the detection, wherein the energy received at each of the pixels is associated with the x-ray pulse. The method further includes multiplexing readouts of analog signals from the array of pixels into two or more parallel channels. The method further includes simultaneously converting (or otherwise in parallel) the analog signals of each of the channels into digital signals and storing the digital signals in memory as frames of data. The method may further include, for example, transmitting the frames of data from the memory, over a Universal Serial Bus, to an imaging system.

Abstract: Techniques are provided for x-ray image data monitoring and signaling for patient safety. A methodology implementing the techniques according to an embodiment includes integrating energy associated with a received x-ray pulse at an array of pixels. The method also includes multiplexing a readout of the integrated energy from the array of pixels, as analog signals, into channels, and performing analog to digital conversion of the analog signals of the channels into digital signals. The method further includes generating an error indicator in response to determining that a calculated mean of the digital signals is either greater than an upper threshold value associated with saturation or less than a lower threshold value associated with underexposure. The method further includes transmitting the error indicator over a Universal Serial Bus, to an imaging system, to terminate transmission of further x-ray pulses.

Abstract: An imaging system may be provided with a backside illuminated pixel array that includes imaging pixels and rows of auto-focus pixels. The imaging pixels may generate image data and the auto-focus pixels may generate application-specific data. The imaging pixels may be provided with an array of color filters. The auto-focus pixels may be provided with rows of color filters that are offset with respect to the imaging pixel color filters. The auto-focus pixel color filters may include clear color filters and opaque color filters for blocking image light received at selected incident angles. The system may include an adjustable lens that focuses light onto the pixel array. The pixel array may be coupled to processing circuitry that determines whether an image is focused based on the application-specific data and may adjust the lens in response to determining that the image is not focused.

Abstract: An imager may include an array of pixels. The pixel array may be arranged in rows and columns. Each pixel of the pixel array may include a photodiode that is coupled to a floating diffusion region by a transfer gate. A source-follower transistor may be coupled between the floating diffusion region and a pixel output node. The imager may include ramp circuitry that provides a ramp signal to the floating diffusion region. A capacitor interposed between the ramp circuitry and the floating diffusion region may be used in conveying the ramp signal to the floating diffusion region. The pixel may be coupled to a comparator that is implemented using separate circuitry or may include portions of the pixel.

Abstract: An imaging system may be provided with a backside illuminated pixel array that includes imaging pixels and rows of auto-focus pixels. The imaging pixels may generate image data and the auto-focus pixels may generate application-specific data. The imaging pixels may be provided with an array of color filters. The auto-focus pixels may be provided with rows of color filters that are offset with respect to the imaging pixel color filters. The auto-focus pixel color filters may include clear color filters and opaque color filters for blocking image light received at selected incident angles. The system may include an adjustable lens that focuses light onto the pixel array. The pixel array may be coupled to processing circuitry that determines whether an image is focused based on the application-specific data and may adjust the lens in response to determining that the image is not focused.

Abstract: An imager may include an array of pixels. The pixel array may be arranged in rows and columns. Each pixel of the pixel array may include a photodiode that is coupled to a floating diffusion region by a transfer gate. A source-follower transistor may be coupled between the floating diffusion region and a pixel output node. The imager may include ramp circuitry that provides a ramp signal to the floating diffusion region. A capacitor interposed between the ramp circuitry and the floating diffusion region may be used in conveying the ramp signal to the floating diffusion region. The pixel may be coupled to a comparator that is implemented using separate circuitry or may include portions of the pixel.

Abstract: An integrated circuit may have rows and columns of imaging pixel arrays. Row driver circuitry and column readout circuitry may be shared between the imaging pixel arrays. Control circuit blocks may bypass inactive pixel arrays and may shift signals between different signal paths on the integrated circuit. The control circuit blocks may include synchronizing circuitry for deskewing control signals and buffer circuitry for regenerating weak signals as they are distributed across the integrated circuit. An array of lenses may be associated with the integrated circuit. The spacing between imaging pixel arrays may differ at different parts of the integrated circuit. Images from multiple image sensor pixel arrays may be combined to form a single digital image. Image sensors may be provided with unique lenses, different color responses, different image pixels, different image pixel patterns, and other differences. Reference pixels may be interposed in the gaps between image sensor arrays.

Abstract: A relatively non-complex signal processor supporting an active pixel sensor imaging system is disclosed. The signal processor only requires the first sample from a group of samples in a multiple sample to be transmitted to the signal processor at full resolution. The subsequent samples in that group can be transmitted using only a subset of least significant bits. The minimum number of required LSBs is based upon the level of noise in the system. In one embodiment, the number of LSBs transmitted is k+2 per sample, where k indicates the number bits corresponding to peak noise. In an alternative embodiment, each subsequent sample is transmitted using only k+1 bits.

Abstract: A relatively non-complex signal processor supporting an active pixel sensor imaging system is disclosed. The signal processor only requires the first sample from a group of samples in a multiple sample to be transmitted to the signal processor at full resolution. The subsequent samples in that group can be transmitted using only a subset of least significant bits. The minimum number of required LSBs is based upon the level of noise in the system. In one embodiment, the number of LSBs transmitted is k+2 per sample, where k indicates the number bits corresponding to peak noise. In an alternative embodiment, each subsequent sample is transmitted using only k+1 bits.

Abstract: A macro pixel is provided. The macro pixel includes at least two color pixel elements. Each color pixel element includes a photoreceptor that in response to receiving light, generates an output signal that is indicative of the quantity of light photons of a color are received. Each of the color pixel elements are configured to receive a corresponding color. The photoreceptor of each color pixel element has a geometry and a responsivity to light that is a function of the geometry of the photoreceptor such that the responsivity of the output signal of the photoreceptor to the corresponding color is controllable by changing the geometry. The geometries of the photoreceptors are selected so that a predetermined relative sensitivity to each color is obtained.

Abstract: An integrated circuit may have rows and columns of imaging pixel arrays. Row driver circuitry and column readout circuitry may be shared between the imaging pixel arrays. Control circuit blocks may bypass inactive pixel arrays and may shift signals between different signal paths on the integrated circuit. The control circuit blocks may include synchronizing circuitry for deskewing control signals and buffer circuitry for regenerating weak signals as they are distributed across the integrated circuit. An array of lenses may be associated with the integrated circuit. The spacing between imaging pixel arrays may differ at different parts of the integrated circuit. Images from multiple image sensor pixel arrays may be combined to form a single digital image. Image sensors may be provided with unique lenses, different color responses, different image pixels, different image pixel patterns, and other differences. Reference pixels may be interposed in the gaps between image sensor arrays.

Abstract: A relatively non-complex signal processor supporting an active pixel sensor imaging system is disclosed. The signal processor only requires the first sample from a group of samples in a multiple sample to be transmitted to the signal processor at full resolution. The subsequent samples in that group can be transmitted using only a subset of least significant bits. The minimum number of required LSBs is based upon the level of noise in the system. In one embodiment, the number of LSBs transmitted is k+2 per sample, where k indicates the number bits corresponding to peak noise. In an alternative embodiment, each subsequent sample is transmitted using only k+1 bits.

Abstract: The invention provides a new method and apparatus for NTSC and PAL image sensors which employs fusion of adjacent row pixel charge samples to generate image data for a row. A variety of fusion schemes are possible for fusing the pixel signals from the adjacent rows. The rows of pixels are scanned so that each scan takes an odd row signal sample and, in some cases, an adjacent even row signal sample when specified conditions are met. One sampled row of the two adjacent rows integrate an image with a first integration period while the other adjacent row integrates an image with a second integration period.

Abstract: A relatively non-complex signal processor supporting an active pixel sensor imaging system is disclosed. The signal processor only requires the first sample from a group of samples in a multiple sample to be transmitted to the signal processor at full resolution. The subsequent samples in that group can be transmitted using only a subset of least significant bits. The minimum number of required LSBs is based upon the level of noise in the system. In one embodiment, the number of LSBs transmitted is k+2 per sample, where k indicates the number bits corresponding to peak noise. In an alternative embodiment, each subsequent sample is transmitted using only k+1 bits.

Abstract: A relatively non-complex signal processor supporting an active pixel sensor imaging system is disclosed. The signal processor only requires the first sample from a group of samples in a multiple sample to be transmitted to the signal processor at full resolution. The subsequent samples in that group can be transmitted using only a subset of least significant bits. The minimum number of required LSBs is based upon the level of noise in the system. In one embodiment, the number of LSBs transmitted is k+2 per sample, where k indicates the number bits corresponding to peak noise. In an alternative embodiment, each subsequent sample is transmitted using only k+1 bits.