High sensitivity thermal radiation detection with an emission microscope with room temperature optics

A microscope comprising:

• a Low Temperature Detector array which outputs an electronic signal proportional to the thermal radiation above 1.5 μm;
• Multiple Objective Lenses for imaging thermal radiation emitted by a device under test and to project an Intermediate image, different objective lenses having different magnifications;
• a Projection Lens system for imaging the Intermediate image on to the detector array;
• a Cold Aperture which is a limiting aperture of the system, located between the projection lens system and the detector array, the said cold aperture absorbing the unwanted thermal radiation emitted within the optical system, and the cold aperture located at a plane conjugate with the exit stop of the objective lens;
• a Cold Optical Filter means which blocks unwanted wavelengths from imaging on the array;
• a Processor means coupled to the low temperature detector array for removing noise and enhancing the signal;
• and
• a Display means coupled to the processor means for displaying a thermal image of the heat emitted by the device under test.