Abstract: A charge transimpedance amplifier (CTIA) input cell includes a high gain capacitor configured to integrate charge arising from photocurrent, a low gain capacitor, and a switching element that can switch the low gain capacitor to be electrically coupled in parallel to the high gain capacitor. In some examples, the switching element is a low gain switch, which can be manually activated to switch in the low gain capacitor. In these examples, the low gain switch can be electrically disposed between the low gain capacitor and a source of the photocurrent. In other examples, the switching element is a low gain transistor, which can be automatically activated to switch in the low gain capacitor when a voltage across the high gain capacitor reaches a specified threshold. In these examples, the low gain capacitor can be electrically disposed between the low gain transistor and the source of the photocurrent.

Abstract: An imaging system implementing a scheme for enhancing the dynamic range of the device. An array of radiation detecting pixels produces an output in response to a stimulus. The signal from each pixel is read once for evaluation. If the voltage at an individual pixel satisfies a programmed condition, such as exceeding a predetermined threshold voltage at a particular time, that pixel is reset and begins producing an output signal anew. If the pixel output signal does not satisfy the condition, it is allowed to continue producing the signal without being reset. After the evaluation read, all of the pixels are then read row by row into a buffer and digitally processed. A memory register tracks which pixels have been reset, and the corresponding output signals are adjusted accordingly. This scheme allows the system to process input signals across a broader range of intensity without losing information due to pixel saturation or sacrificing sensitivity.

Abstract: An imaging system implementing a scheme for enhancing the dynamic range of the device. An array of radiation detecting pixels produces an output in response to a stimulus. The signal from each pixel is read once for evaluation. If the voltage at an individual pixel satisfies a programmed condition, such as exceeding a predetermined threshold voltage at a particular time, that pixel is reset and begins producing an output signal anew. If the pixel output signal does not satisfy the condition, it is allowed to continue producing the signal without being reset. After the evaluation read, all of the pixels are then read row by row into a buffer and digitally processed. A memory register tracks which pixels have been reset, and the corresponding output signals are adjusted accordingly. This scheme allows the system to process input signals across a broader range of intensity without losing information due to pixel saturation or sacrificing sensitivity.