Radiation clinical thermometer

• US 5,024,533 A
• Filed: 05/10/1990
• Issued: 06/18/1991
• Est. Priority Date: 04/12/1988
• Status: Expired due to Term

• Current Assignee: Citizen Holdings Co., Ltd.
• Original Assignee: Citizen Watch Co Limited (Citizen Electronics Company Limited)
• Inventors: Yamada, Masato, Egawa, Shunji
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): GUTIERREZ, DIEGO F
• Application Number:
  US07/522,337
• Time in Patent Office: 404 Days
• Field of Search: 374/126, 374/129, 374/121, 374/164, 374/170, 374/128, 374/130, 374/132, 374/133, 374/2, 128/664, 128/736
• US Class Current: 374/126
• CPC Class Codes: G01J 2001/4433 Peak sensing
• CPC Class Codes: G01J 5/02 Constructional details
• 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 5/064 Ambient temperature sensor; Housing temperature sensor; Constructional details thereof
• CPC Class Codes: G01J 5/08 Optical arrangements
• CPC Class Codes: G01J 5/0801 Means for wavelength selection or discrimination
• CPC Class Codes: G01J 5/0818 Waveguides
• CPC Class Codes: G01J 5/0875 Windows; Arrangements for fastening thereof
• CPC Class Codes: G01J 5/16 Arrangements with respect to the cold junction; Compensating influence of ambient temperature or other variables

Abstract

A radiation clinical thermometer has a probe with an optical guide and an infrared sensor, a detection signal processing section, a body temperature operating section, and a display unit. A filter correction system for setting a correction value based on the transmission wavelength characteristics of a filter is also provided. The body temperature operating section receives infrared data, temperature-sensitive data, which takes into account the temperature equilibrium between the optical guide and the infrared sensor, and a correction value from the filter correction section so as to calculate body temperature data.

Claims

1. A radiation clinical thermometer comprising:

a probe including an optical means having an optical guide for collecting infrared radiation from an object to be measured, an infrared sensor for converting infrared radiation energy collected through said optical guide into an electrical signal, a first temperature-sensitive sensor for measuring a first temperature of said infrared sensor and an ambient temperature thereof, and a second temperature-sensitive sensor for measuring a second temperature of said optical guide;

detection signal processing means for receiving electrical signals from said infrared sensor and said temperature-sensitive sensors and outputting the electrical signals as digital infrared data and digital temperature-sensitive data, respectively;

body temperature operating means for calculating body temperature data by correcting an electrical signal from said infrared signal dependent on the extent of thermal equilibrium between said infrared sensor and said optical guide measured on the basis of electrical signals from said first temperature-sensitive sensor and said second temperature-sensitive sensor; and

a display unit for displaying a body temperature in accordance with the body temperature data.

2. A thermometer according to claim 1 wherein said second temperature sensitive sensor is attached to said optical means.

3. A thermometer according to claim 1 further comprising a temperature difference detector for detecting a difference between said first temperature and said second temperature and means for preventing display of the body temperature in the presence of a temperature difference between said first temperature and said second temperature.

4. A thermometer according to claim 3 comprising means for displaying the body temperature where the temperature difference between the first and second temperatures is smaller than a predetermined value.

5. A thermometer according to claim 4 comprising means for adding a correction value dependent upon the temperature difference.

6. A thermometer according to claim 1 wherein the infrared sensor is arranged at one end of the optical guide and the first temperature-sensitive sensor is arranged near the infrared sensor, and wherein the probe includes a metal housing having a high thermal conductivity coupling the optical guide, the infrared sensor, and the first temperature-sensitive sensor to each other.

7. A thermometer according to claim 6 wherein the metal housing includes an opening exposing the optical means for attaching a second temperature-sensitive sensor to the optical guide.

8. A thermometer according to claim 1 wherein the detection signal processing means is incorporated in an IC chip, and further comprising a circuit board for mounting the IC chip and the second temperature-sensitive sensor.