Ambient and perfusion normalized temperature detector

• US 7,314,309 B2
• Filed: 11/14/2005
• Issued: 01/01/2008
• Est. Priority Date: 06/24/1997
• Status: Expired due to Fees

• Current Assignee: Exergen Corporation
• Original Assignee: Exergen Corporation
• Inventors: Pompei, Francesco
• Primary Examiner(s): VERBITSKY, GAIL KAPLAN
• Application Number:
  US11/273,260
• Publication Number:
  US 20060222048A1
• Time in Patent Office: 778 Days
• Field of Search: 374/120, 374/121, 374/133, 374/130, 374/163, 374/183, 374/128, 374102-104, 600/474, 600/549, 702/139, 702/133, 702/131, 702/99
• US Class Current: 374/133
• CPC Class Codes: G01J 5/0022 for sensing the radiation of moving bodies
• CPC Class Codes: G01J 5/0025 Living bodies ear thermometers G01J5/0011; detecting, measuring or recording for diagnostic purposes A61B5/00
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/025 Interfacing a pyrometer to an external device or network; User interface
• CPC Class Codes: G01J 5/026 Control of working procedures of a pyrometer, other than calibration; Bandwidth calculation; Gain control
• CPC Class Codes: G01J 5/0265 Handheld, portable ear thermometers G01J5/049
• CPC Class Codes: G01J 5/04 Casings
• CPC Class Codes: G01J 5/049 Casings for tympanic thermometers
• CPC Class Codes: G01J 5/06 Arrangements for eliminating effects of disturbing radiation; Arrangements for compensating changes in sensitivity for adjusting of solid angle of collected radiation G01J5/07; means for wavelength selection G01J5/0801
• CPC Class Codes: G01J 5/064 Ambient temperature sensor; Housing temperature sensor; Constructional details thereof
• CPC Class Codes: G01J 5/16 Arrangements with respect to the cold junction; Compensating influence of ambient temperature or other variables

Abstract

A body temperature detector is particularly suited to axillary temperature measurements of adults. The radiation sensor views a target surface area of the body and electronics compute an internal temperature of the body as a function of ambient temperature and sensed surface temperature. The function includes a weighted difference of surface temperature and ambient temperature, the weighting being varied with target temperature to account for varying perfusion rate. Preferably, the coefficient varies from a normal of about 0.13 through a range to include 0.09. The ambient temperature used in the function is assumed at about 80° F. but modified with detector temperature weighted by 20%.

Claims

1. A body temperature detector comprising:

a radiation sensor which views a target surface area of the body and provides a radiation sensor output;

an ambient temperature sensor; and

electronics coupled to the radiation sensor and ambient temperature sensor, which compute an internal temperature of the body as a function of the ambient temperature and a target surface temperature derived from the radiation sensor output, the function including a difference of the target surface temperature and the ambient temperature weighted by a weighting coefficient, the weighting coefficient being varied with the sensed target surface temperature.