Infrared sensor amplification techniques for thermal imaging

摘要

Thermal imaging devices, systems, and methods are provided with IR sensor amplification techniques that in some cases provide a gain transfer function having at least two different gain regions. One thermal imaging camera includes an IR camera module, processing circuitry, and an amplifier stage that comprises a continuous gain function including at least two gain regions having different gains. In some cases a thermal imager is provided with saturation circuitry configured to reduce the gain of the amplifier stage in order to provide one of at least two different gain regions within the continuous gain function. In some cases amplification techniques provide a continuous gain function that includes both linear and nonlinear gain regions. One or more gain regions may further be calibrated for measuring temperature.

主权项

1. A thermal imaging camera, comprising:
an infrared (IR) camera module comprising an IR sensor for detecting IR radiation from a target scene, the IR sensor comprising a plurality of IR sensor elements arranged to receive the IR radiation from the target scene, each IR sensor element corresponding to part of a thermal image of the target scene and configured to produce an IR sensor element output signal based on an electrical characteristic that varies corresponding to an amount of the IR radiation received by the IR sensor element; an amplifier stage coupled to the IR sensor for receiving the IR sensor element output signals from each of the plurality of IR sensor elements, the amplifier stage comprising a gain provided according to a continuous gain function configured to amplify the IR sensor element output signals from each of the plurality of IR sensor elements through a continuous range of IR sensor element output values to generate amplifier output signals corresponding to each of the plurality of IR sensor elements, the amplifier output signals having a corresponding continuous range of amplifier output values, the continuous gain function comprising a first gain region having a first gain and a second gain region having a second gain different than the first gain, wherein the first gain region is applied to a first range of IR sensor element output values and generates a corresponding first range of amplifier output values and the second gain region is applied to a second range of IR sensor element output values and generates a corresponding second range of amplifier output values; and processing circuitry coupled to the amplifier stage, the processing circuitry configured to generate the thermal image of the target scene based on the amplifier output signals.