Abstract: A solid state laser visible light source (26) passes light through a scanning mechanism (22) otherwise used to convey radiation from a target (12) to a detector (28) of a scanning radiation sensor (10) to mark with light a line (16) which is continuous when the sensor (10) is operating in a continuous mode, but when the sensor is operated in a spot mode in which a plurality of spots along a scan line are to be individually measured, a control (30) causes the light source to turn on and off at the correct times in the scan cycle to cause the light source (26) to mark the plural spots on the scan line (16). A CCD camera (40) with an automatic gain control circuit (46) is used in conjunction with a band pass light filter (36) to substantially enhance viewability of the image of the light markings (16) on the target (12) on a display (44).

Abstract: An infrared thermometer (10) with a fixed aperture (99), focusable remote pickup head (12) conveys infrared light (16) from a target (14) to a photosensor (52) of a defocused sensor head (20). The remote pickup head (12) has a reimaging lens (84) and means for selectively adjusting the focus of the lens (84) relative to the target (14) after the pickup head has been fixedly mounted. The aperture setting is kept fixed during the focus adjustment to eliminate the need to recalibrate after the focus adjustment. The defocused sensor head (20) has a defocused relay lens (50) which is selectively out of focus to convey a slightly blurred, out of focus image of the output end of the fiber optic cable (18) to the photosensor (52) to reduce noise, average the light signal and reduce calibration difficulties due to high intensity spots in the image field and to make the unit less susceptible to misfocusing.

Abstract: An infrared thermometer (10) with a fixed aperture (99), focusable remote pickup head (12) conveys infrared light (16) from a target (14) to a photosensor (52) of a defocused sensor head (20). The remote pickup head (12) has a reimaging lens (84) and means for selectively adjusting the focus of the lens (84) relative to the target (14) after the pickup head has been fixedly mounted. The aperture setting is kept fixed during the focus adjustment to eliminate the need to recalibrate after the focus adjustment. The defocused sensor head (20) has a defocused relay lens (50) which is selectively out of focus to convey a slightly blurred, out of focus image of the output end of the fiber optic cable (18) to the photosensor (52) to reduce noise, average the light signal and reduce calibration difficulties due to high intensity spots in the image field and to make the unit less susceptible to misfocusing.

Abstract: An apparatus and method for measuring the thickness of a protective film on a sheet or substrate as the sheet moves past the apparatus. The apparatus includes a black-body radiator in the form of an isothermal cavity having an opening across which the sheet is moved. The cavity has an observation window opposite the opening through which window the surface of the moving sheet may be scanned. A radiation pyrometer scans the moving sheet through the observation opening. Rays from the radiator pass through the film to the substrate, are reflected by the substrate, and pass back through the film and through the window to the pyrometer. The absorption of rays from the black-body radiator as they pass through the film is a function of the thickness of the portion of the film being observed. The radiation pyrometer thus receives an output which is a function of the film thickness being measured.