An imaging system whose Field of View FOV experiences occasional motion in relation to viewed scenes may be configured to reduce Fixed Pattern Noise (FPN) of acquired image data. FPN may be reduced by developing a pixel by pixel FPN correction term through a series of steps including blurring the image, identifying pixels to exclude from some calculations, a motion detector and an FPN updater for frames under motion and an FPN decay element for frames that are still.

A method, including receiving signals, from a rectangular array of sensor elements arranged in rows and columns, corresponding to an image captured by the array. The method also includes analyzing the signals along a row or a column to identify one or more local turning points, and processing the signals at the identified local turning points to recognize fixed pattern noise in the captured image. The method further includes correcting values of the signals from the sensor elements at the identified local turning points so as to reduce the fixed pattern noise in the image.

One or more techniques and/or systems are described for addressing (e.g., during calibration) pixel-by-pixel variations in an image modality that utilizes photon counting techniques, such as by adjusting a number of photons detected by certain pixels (e.g., redistributing or reallocating detected photons among pixels). Such variations may cause an effective area of one or more pixels of a detector array to be larger than the effective area of other pixels, resulting in more photons being counted by some pixels than others, which can degrade resulting images. Accordingly, photons are redistributed as provided herein so that, when exposed to substantially uniform radiation, photon counts of neighboring pixels are substantially equal, statistical noise among neighboring pixels is substantially equal, and a signal-to-noise ratio among neighboring pixels is substantially equal. By redistributing photons as described herein, a spatial uniformity and/or a modulated transfer function (MTF) associated with a detector array may be improved.

Various techniques are provided for implementing, operating, and manufacturing infrared imaging devices using integrated circuits. In one example, a system includes a focal plane array (FPA) integrated circuit comprising an array of infrared sensors adapted to image a scene, a plurality of active circuit components, a first metal layer disposed above and connected to the circuit components, a second metal layer disposed above the first metal layer and connected to the first metal layer, and a third metal layer disposed above the second metal layer and below the infrared sensors. The third metal layer is connected to the second metal layer and the infrared sensors. The first, second, and third metal layers are the only metal layers of the FPA between the infrared sensors and the circuit components. The first, second, and third metal layers are adapted to route signals between the circuit components and the infrared sensors.

Various techniques are provided to capture one or more thermal image frames using an infrared sensor array that is fixably positioned to substantially de-align rows and columns of infrared sensors. In one example, an infrared imaging system includes an infrared sensor array comprising a plurality of infrared sensors arranged in rows and columns and adapted to capture a thermal image frame of a scene exhibiting at least one substantially horizontal or substantially vertical feature. The infrared imaging system also includes a housing. The infrared sensor array is fixably positioned within the housing to substantially de-align the rows and columns from the feature while the thermal image frame is captured.

The present invention provides a method for removing a haze in a single image. In the present invention, a transmission is estimated by using a dark channel prior obtained from a hazy input image. The estimated transmission includes a block artifact. In an exemplary embodiment of the present invention, in order to preserve an edge and remove the block artifact, a refined transmission value is obtained by performing WLS filtering by using an estimated transmission value and a morphologically-processed input image, the image is restored based on the refined transmission value, and then multi-scale tone manipulation image processing is performed.

Methods of calibrating a linear-logarithmic image sensor pixel include performing a reset of the pixel in advance of establishing a leakage current between a photodiode and a floating diffusion region of the pixel. A first voltage of the floating diffusion region is then read through a source follower and selection transistor, after the leakage is terminated. A step is then performed to transfer charge between the photodiode and the floating diffusion region of the pixel so that a voltage of a cathode of the photodiode is increased. Thereafter, a second voltage of the floating diffusion region is read. The first and second read voltages are then used to perform a calibration operation. These steps may be repeated to establish another leakage current of different duration/magnitude and yield third and fourth read voltages, which support further calibration.

The effect of ambient light on a measurement taken by an imaging pixel may be reduced by employing two optical filters. The two filters may have narrow passbands that are close to each other but do not overlap. The first filter may allow ambient and active light to pass. The second filter may allow ambient light to pass but may block active light. The ambient and active light that passes through the first filter may cause electrical charge to be generated in a photodiode of the pixel. The ambient light that passes through the second filter and strikes another pixel element may control the amperage of an electrical current that depletes charge from the photodiode. For instance, the other element may be a photoresistor, the light-dependent resistance of which controls the amperage, or may be a second photodiode that generates charge that controls a transistor that controls the amperage.

Imagers and associated devices and systems are disclosed herein. In one embodiment, an imager includes a pixel array and control circuitry operably coupled to the pixel array. The pixel array includes an imaging pixel configured to produce a reset signal and a non-imaging pixel configured to produce a nominal reset signal. The control circuitry is configured to produce an output signal based at least in part on one of (a) the nominal reset signal when distortion at the imaging pixel exceeds a threshold and (b) the reset signal when distortion does not exceed the threshold.

A radiation imaging apparatus, comprising a sensor array in which a plurality of sensors are arranged, each includes a first holding unit for holding a first signal obtained with a first sensitivity and a second holding unit for holding a second signal obtained with a second sensitivity, a row selecting unit for selecting each sensor on a row basis, a signal readout unit for reading out a signal from each of the selected sensors, and a control unit configured to perform first control to control the sensor array so as to make the first holding units hold the first signals and make the second holding units hold the second signals, and perform second control to control the row selecting unit so as to make the signal readout unit read out the first and the second signals.