Infrared thermometry system and method
AssigneeIVAC Corporation
InventorsKenneth A. Beckman, John A. Graham
Life of this patent
Estimating the term…
Abstract
A biomedical thermometer for taking the temperature of a person at various body sites, including the ear, includes a radiation detector, a temperature detector for measuring the temperature of the radiation detector, and a heating and cooling unit for changing the temperature of the radiation detector. The system also includes a temperature processor for generating an output proportional to the absolute temperature of the radiation detector, responsive to signals generated by the radiation detector and the temperature detector.
Claims17
An apparatus for measuring electromagnetic radiation emitted from a target, comprising:
- (a) radiation detector means for receiving radiation from said target, adapted to generate a first electrical signal proportional to the difference between the temperature of said target and the temperature of said radiation detector means;
- (b) a temperature detector for measuring the temperature of said radiation detector means, and adapted to generate a second electrical signal indicative of the temperature of said radiation detector means;
- and
- (c) means for changing the temperature of said radiation detector means, said means for changing the temperature of said radiation detector means being responsive to said first signal, and further including means for controlling said means for changing the temperature to reduce the absolute value of said first signal to substantially zero.
An apparatus for measuring electromagnetic radiation emitted from a target, comprising:
- (a) radiation detector means for receiving radiation from said target, adapted to generate a first electrical signal proportional to the difference between the temperature of said target and the temperature of said radiation detector means;
- (b) a temperature detector for measuring the temperature of said radiation detector means, and adapted to generate a second electrical signal indicative of the temperature of said radiation detector means;
- (c) means for changing the temperature of said radiation detector means;
- said means for changing the temperature of said radiation detector means including means for causing the temperature of said radiation detector means to sweep through a temperature range encompassing an initially determined approximate temperature of said target;
- and
- temperature processor means responsive to said first signal and said second signal, and adapted to generate a third signal proportional to the absolute temperature of said radiation detector means.
A method for measuring radiation emitted from a target, utilizing an apparatus including a radiation detector having an output proportional to the difference in temperature of said radiation detector and said target, a temperature detector, and means for changing the temperature of said radiation detector, comprising the steps of:
- (a) measuring the output from said radiation detector;
- (b) changing the temperature of said radiation detector to cause said radiation detector to generate a signal having a substantially zero absolute value;
- and
- (c) measuring the temperature of said radiation detector to determine the temperature of said target when absolute value of said signal generated by said radiation detector is substantially zero.
A method for measuring electromagnetic radiation emitted from a target, utilizing an apparatus including a radiation detector having an output proportional to the difference in temperature between said radiation detector and said target, a temperature detector, and a means for changing the temperature of said radiation detector, comprising the steps of:
- (a) controlling the temperature of said radiation detector to approximate an initial estimated target temperature;
- (b) measuring the output of said radiation detector;
- (c) determining a subsequent estimated target temperature based upon said initial estimated target temperature and said radiation detector output;
- and
- (d) repeating steps (a), (b), and (c) to determine successive approximations of estimated target temperature.
Dependencies are inferred from the claim text.