Infrared temperature monitoring apparatus having means for sky radiation compensation

摘要

An infrared thermometer primarily for agricultural applications utilizes an additional infrared sensor oriented for detection of sky radiation to compensate for reflection of sky radiation from the plant or other object to which the thermometer is directed. Preferably implemented in a gunlike, hand-held instrument, the invention utilizes a potentiometer for adjusting the signal level derived from a wide-angle, sky-directed sensor to account for changes in plant reflectivity characteristics. The adjusted signal is then summed with the signal derived from the conventional object-directed sensor to produce a composite signal which is applied to a meter-like device for display of object temperature with improved accuracy.