Abstract: A bolometer circuit includes a substrate on which a focal plane array (FPA) of active bolometers is provided. Each active bolometer is configured to receive external infrared (IR) radiation and substantially thermally isolated from the substrate. The bolometer circuit also includes one or more blind arrays of blind bolometers shielded from the external IR radiation and substantially thermally isolated from the substrate. Noises in outputs from each column and/or each row of the FPA are corrected, reduced, or suppressed based on a statistical property of outputs from a corresponding column or row of the one or more blind arrays. Noise in each frame of IR image captured by the FPA may also be corrected, reduced, or suppressed using the one or more blind arrays.

Abstract: A bolometer circuit may include an active bolometer configured to receive external infrared (IR) radiation. The bolometer circuit may be configured to reduce power consumption at high temperatures. In particular, the bolometer circuit may include additional resistors provided in the resistive loads for bolometer conduction paths to limit power at high temperatures. In some embodiments, the bias (e.g., a voltage level) to the gates of transistors in the resistive loads for the bolometer conduction paths may be adjusted based on temperature to limit power and/or current at high temperatures. In bolometer circuits with a feedback resistor provided across an amplifier to configure a feedback amplifier, a circuit with adjustable amplifier power may be provided to save power. In some embodiments, a bolometer circuits may be provided with reduced gains to allow for very hot scenes to be imaged without railing the output.

Abstract: Techniques are disclosed for systems and methods for facilitating infrared imaging in multiple imaging modes. A device may include an infrared image capture circuit and at least one processing circuit. The infrared image capture circuit may be configured to detect first infrared data and generate a first pixel value based on the first infrared data and a first imaging mode among multiple imaging modes. The at least one processing circuit may be configured to compare the first pixel value to a set of saturation threshold values associated with the first imaging mode. The at least one processing circuit may be further configured to select an imaging mode among the multiple imaging modes based on the comparison of the first pixel value. The at least one processing circuit may be further configured to set the infrared image capture circuit to generate a second pixel value based on the selected imaging mode.

Abstract: Techniques are disclosed for systems and methods for facilitating pixel readout with partitioned analog-to-digital conversion. A device includes a detector, a capacitor coupled to the detector, a counter circuit coupled to the capacitor, a reset circuit coupled to the capacitor, and a processing circuit. The detector is configured to detect electromagnetic radiation associated with a scene and generate an associated detection signal. The capacitor is configured to, during an integration period, accumulate a voltage based on the detection signal. The counter circuit is configured to, during the integration period, adjust a counter value based on a comparison of the voltage and a reference voltage. The reset circuit is io configured to, during the integration period, reset the capacitor based on the comparison. The processing circuit is configured to generate a digital detector output based on the counter value when the integration period has elapsed. Related methods are also provided.

Abstract: Techniques are disclosed for facilitating pulse detection and imaging. In one example, a device includes a detector configured to detect electromagnetic radiation and generate a detection signal based on the detected electromagnetic radiation. The device further includes an input circuit configured to provide, based on the detection signal, a first signal and a second signal. The device further includes an imaging integration circuit configured to generate an image of at least a portion of a scene based at least in part on the first signal. The device further includes a pulse detection circuit configured to perform pulse detection to generate an indication of whether a pulse is detected in the portion of the scene based at least in part on the second signal. Related methods and systems are also provided.

Abstract: A bolometer circuit may include an active bolometer configured to receive external infrared (IR) radiation and a resistive load, which are configured to be connected in series in a bolometer conduction path from a supply voltage node to a common voltage node. A node in the bolometer conduction path between the resistive load and the active bolometer is coupled to a first input of an op-amp. A variable voltage source is coupled to a second input of the op-amp to provide a reference voltage level. The op-amp maintains the reference voltage level at the first input to generate a current flow in response to a resistance change of the active bolometer due to the external IR radiation. The amplifier circuit may be configured as a feedback amplifier or an integrating amplifier. The bolometer circuit may be configured to enable a low-power mode of operation.

Abstract: Various techniques are disclosed for bolometer circuits and related methods for thermal imaging in a difference domain, where each pixel value represents a difference in incident IR radiation intensity between adjacent bolometers. For example, a bolometer circuit may include an array of bolometers each configured to generate a pixel signal in response to a bias and incident infrared radiation. Each column of the bolometer array may comprise an amplifier, a first plurality of switches each configured to selectively provide a supply voltage to a respective one of bolometers of the each column, a second plurality of switches each configured to selectively route a difference of the pixel signals of a respective adjacent pair of the bolometers of the each column to an input of the amplifier, and a third plurality of switches configured to selectively provide a common voltage to a respective one of the bolometers of the each column.

Abstract: A bolometer circuit may include an active bolometer configured to receive external infrared (IR) radiation and a resistive load, which are configured to be connected in series in a bolometer conduction path from a supply voltage node to a common voltage node. A node in the bolometer conduction path between the resistive load and the active bolometer is coupled to a first input of an op-amp. A variable voltage source is coupled to a second input of the op-amp to provide a reference voltage level. The op-amp maintains the reference voltage level at the first input to generate a current flow in response to a resistance change of the active bolometer due to the external IR radiation. The amplifier circuit may be configured as a feedback amplifier or an integrating amplifier. The bolometer circuit may be configured to enable a low-power mode of operation.

Abstract: Various techniques are disclosed for bolometer circuits and related methods for thermal imaging in a difference domain, where each pixel value represents a difference in incident IR radiation intensity between adjacent bolometers. For example, a bolometer circuit may include an array of bolometers each configured to generate a pixel signal in response to a bias and incident infrared radiation. Each column of the bolometer array may comprise an amplifier, a first plurality of switches each configured to selectively provide a supply voltage to a respective one of bolometers of the each column, a second plurality of switches each configured to selectively route a difference of the pixel signals of a respective adjacent pair of the bolometers of the each column to an input of the amplifier, and a third plurality of switches configured to selectively provide a common voltage to a respective one of the bolometers of the each column.