Method for determining temperature, radiation thermometer with several infrared sensor elements

• US 6,898,457 B1
• Filed: 08/26/1999
• Issued: 05/24/2005
• Est. Priority Date: 09/16/1998
• Status: Expired due to Fees

• Current Assignee: Helen of Troy Limited
• Original Assignee: Braun GmbH (The Procter & Gamble Company)
• Inventors: Kraus, Bernhard, Beerwerth, Frank
• Primary Examiner(s): MANTIS MERCADER, ELENI M
• Application Number:
  US09/763,436
• Time in Patent Office: 2,098 Days
• Field of Search: 600/474, 600/549, 600/412, 600/473, 600/475, 600/424
• US Class Current: 600/474
• CPC Class Codes: G01J 5/0003 for sensing the radiant heat transfer of samples, e.g. emittance meter
• CPC Class Codes: G01J 5/0011 Ear thermometers G01J5/021 and G01J5/049 take precedence
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/0275 Control or determination of height or distance or angle information for sensors or receivers
• CPC Class Codes: G01J 5/07 Arrangements for adjusting the solid angle of collected radiation, e.g. adjusting or orienting field of view, tracking position or encoding angular position optical collimating elements G01J5/0806
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0806 Focusing or collimating elements, e.g. lenses or concave mirrors
• CPC Class Codes: G01J 5/0846 having multiple detectors for performing different types of detection, e.g. using radiometry and reflectometry channels

Abstract

The invention is directed to a method for determining a temperature by means of a radiation thermometer with multiple infrared sensor elements detecting infrared radiation from different regions and delivering corresponding temperature signals, in particular to a method for taking a patient'"'"'s temperature by means of an ear thermometer. The method of the present invention is based on the known fact that the tympanic membrane has a higher temperature than the ear canal. Hence part of the sensor elements, that is, those that view the tympanic membrane, will detect a higher temperature than the remaining sensor elements that view the ear canal. According to the present invention, for evaluation only the temperature signal of that sensor element is used that supplies the peak temperature value by comparison with the other sensor elements.

Claims

1. A method for determining a temperature by means of a radiation thermometer with multiple infrared sensor elements detecting infrared radiation from different regions and delivering corresponding temperature signals, in particular for taking a patient'"'"'s temperature in the ear, in which for determining the temperature only the temperature signal of that particular sensor element is used which supplies the peak temperature value (T_max) by comparison with the remaining sensor elements, characterized in that a signal can be produced which indicates the direction in which a user is required to pivot the thermometer when the higher temperature values are measured in the edge region of the thermometer'"'"'s field of view.

2. The method as claimed in claim 1, characterized in that a warning signal is produced when the number of higher temperature values, related to the aggregate of the temperature values supplied by the sensor elements, drops below a predetermined threshold value.

3. The method as claimed in claim 2, characterized in that the warning signal is not produced when the ambient temperature is within or exceeds the range of the body temperature.

4. A radiation thermometer, in particular for taking a patient'"'"'s temperature in the ear, with multiple infrared sensor elements for the detection of infrared radiation from different regions, in which for determining the temperature only the temperature signal of that particular sensor element is used which supplies the peak temperature value (T_max) by comparison with the remaining sensor elements, characterized in that it includes an evaluation device for the temperature signals of the sensor elements, which can produce a signal indicating the direction in which a user is required to pivot the thermometer when the higher temperature values are measured in the edge region of the thermometer'"'"'s field of view.

5. The radiation thermometer as claimed in claim 4, characterized in that it includes an optical system (30) comprising at least a lens, a mirror and/or multiple light guiding fibers or reflector tubes capable of directing infrared radiation from different regions to the individual sensor elements (E_ij).

6. The radiation thermometer as claimed in claim 4 or 5, characterized in that the sensor elements (E_ij) are arranged in a row or matrix pattern.

7. The radiation thermometer as claimed in claim 4, 6, or 5, characterized in that at least one sensor element is provided which is shielded against infrared radiation emitted by the object of measurement.