Hot stop aperture fixtures for thermal imaging measurements

A device comprising:

• a hot stop assembly configured to be disposed between a thermal imaging camera and an optical assembly that is able to be positioned between the thermal imaging camera and a target, the hot stop assembly comprising:
• a hot aperture having a first surface configured to face the target and a second surface configured to face an interior portion of the hot stop assembly;
• and
• a cold aperture having a first surface configured to face the camera and a second surface configured to face the interior portion of the hot stop assembly,
• wherein the hot aperture is thermally isolated from the cold aperture.

A method comprising:

• generating thermal images of a target using a camera;
• manipulating thermal radiation from the target before the thermal radiation reaches the camera using an optical assembly disposed between the camera and the target;
• and
• reducing bias effects of background radiation on the thermal images of the target using a hot stop assembly disposed between the camera and the optical assembly;
• wherein the hot stop assembly comprises (i) a hot aperture having a first surface facing the target and a second surface facing an interior portion of the hot stop assembly and (ii) a cold aperture having a first surface facing the camera and a second surface facing the interior portion of the hot stop assembly;
• and
• wherein the hot aperture is thermally isolated from the cold aperture.