Radiation heat loss detector

• US 4,343,182 A
• Filed: 07/14/1980
• Issued: 08/10/1982
• Est. Priority Date: 07/14/1980
• Status: Expired due to Term

• Current Assignee: PNC Bank National Association (The PNC Financial Services Group, Inc.)
• Original Assignee: Exergen Corporation
• Inventors: Pompei, Francesco
• Primary Examiner(s): Ruehl, Charles A.
• Assistant Examiner(s): Corr, Denis E.
• Application Number:
  US06/168,532
• Time in Patent Office: 757 Days
• Field of Search: 73/15 R, 73/15 FD, 73/355 R, 73/190 H, 250/338, 250/353, 367/96, 367/108, 354/195, 354/198, 354/106, 354/289, 356/3
• US Class Current: 374/31
• CPC Class Codes: G01J 2005/0077 Imaging
• CPC Class Codes: G01J 5/02 Constructional details
• CPC Class Codes: G01J 5/0265 Handheld, portable ear thermometers G01J5/049
• CPC Class Codes: G01J 5/0275 Control or determination of height or distance or angle information for sensors or receivers
• CPC Class Codes: G01J 5/064 Ambient temperature sensor; Housing temperature sensor; Constructional details thereof
• 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 5/085 having a through-hole enabling the optical elements to fulfil an additional optical function, e.g. mirrors or gratings having a through-hole for a light collecting or light injecting optical fiber
• CPC Class Codes: G01J 5/0859 Sighting arrangements, e.g. cameras
• CPC Class Codes: G01K 17/00 Measuring quantity of heat measuring temperature by calorimetry G01K3/00 - G01K11/00; specially adapted for measuring thermal properties of materials, e.g. specific heat, heat of combustion G01N

Abstract

In a radiation heat loss detector, radiation from an extended surface area is detected with a sensor having a wide field of view closely matching that of an associated camera. By simultaneously photographing the surface area of interest and detecting the radiation from that same area, a clear record is provided for future use. A wide band radiation sensor is used. Compensation for environmental radiation is made by first viewing the environment with the sensor and holding the sensed signal and then subtracting that signal from the flux detected when the sensor faces the extended surface area. The date and time are also recorded on the photograph. A sonar device positioned on the camera provides a distance indication which, with a known field of view, allows for a determination of the total flux from the surface area, a determination of convective heat losses from the surface and a correction for atmospheric absorption of the radiant energy.

Claims

1. A radiation heat loss detector assembly for providing an indication of the heat loss from an extended surface area comprising:

a camera for providing a visual image of said surface area on photographic film;

a thermal radiation sensor having a wide field of view of at least about 20°

at any instant substantially matching the field of view of a designated area of the image recorded on the film;

display means responsive to the output of the radiation detector for providing an illuminated display indicative of the radiation heat loss from said extended surface area; and

means for recording a visual image of the display with the image of the surface area on the photographic film.

2. A radiation heat loss detector assembly as claimed in claim 1 further comprising a temperature sensor and means to compensate for heat radiated from the radiation sensor to determine the actual heat radiated from the said surface area.

3. A radiation heat loss detector assembly as claimed in claim 1 further comprising means for detecting the distance between the radiation detector and said surface area and electrical circuit means for determining the total heat loss from the surface area based on the distance measurement.

4. A radiation heat loss detector assembly as claimed in claim 1 further comprising a date and time display and means for providing a visual image of that display with the image of the surface area on the photographic film.

5. A radiation heat loss detector assembly as claimed in claim 1 wherein the field of view of the camera optics and the thermal radiation detector is about 40 degrees.

6. A radiation heat loss detector assembly as claimed in claim 1 wherein the thermal radiation detector is a wide band detector for sensing radiation having wavelengths within the range of about 1μ

to 50μ

.

7. A radiation heat loss detector assembly for providing an indication of the heat loss from an extended surface area comprising:

a camera for providing a visual image of said surface area on photographic film;

a thermal radiation sensor having a wide field of view of at least about 20°

at any instant substantially matching the field of view of a designated area of the image on the film, the radiation sensor having a wide band response;

means for sensing wide band, wide field-of-view radiation from the environment incident on the surface area and an electrical circuit for compensating a radiation signal for said surface area with the radiation signal for the environment to provide a radiation heat loss signal;

display means for providing an illuminated display indicative of the radiation heat loss from said surface area; and

means for providing a visual image of the display with the image of the surface area on the photographic film.

8. A radiation heat loss detector assembly as claimed in claim 7 including a single radiation sensor and electrical circuit means for sampling and holding an environmental radiation signal prior to sensing of the surface area radiation.

9. A radiation heat loss detector assembly as claimed in claim 7 further comprising a date and time display and means for providing a visual image of that display with the image of the surface area on the photographic film.

10. A radiation heat loss detector assembly as claimed in claim 7 wherein the field of view of the camera optics and the thermal radiation detector is about 40 degrees.

11. A radiation heat loss detector assembly as claimed in claim 7 further comprising means for detecting the distance between the radiation sensor and said surface area.

12. A radiation heat loss detector assembly as claimed in claim 11 further comprising an electrical circuit for determining the total flux from said surface area as a function of the flux detected by said radiation sensor, the distance between the sensor and surface area and the field of view of the sensor.

13. A radiation heat loss detector assembly as claimed in claim 11 further comprising an electrical circuit for providing an indication of the convective heat loss from said surface area as a function of the sensed radiation and the distance between the radiation sensor and surface area.

14. A radiation heat loss detector assembly as claimed in claim 11 further comprising an electrical circuit for providing an indication of the heat flux from said surface area with compensation for the radiation absorbed by the atmosphere between the surface area and the sensor.

15. A radiation heat loss detector assembly as claimed in claim 7 further comprising a temperature sensor and means to compensate for heat radiated from the radiation sensor to determine the actual heat radiated from the said surface area.

20. A radiation heat loss detector assembly as claimed in claim 3, 11 or 16 further comprising means for recording a visual image on the photographic film indicative of the dimensional scale of the image of said surface area.

21. A radiation heat loss detector assembly as claimed in claim 20 wherein the image indicative of scale includes a digital display indicating linear units on a linear scale.

16. A radiation heat loss detector assembly for providing an indication of the heat loss from an extended surface area comprising:

a camera for providing a visual image of said surface area on photographic film;

a thermal radiation sensor having a field of view of about 40°

at any instant substantially matching the field of view of a designated area of the image on the film, the radiation sensor having a wide band response;

means for detecting the distance between the radiation sensor and said surface area;

means for determining radiation losses from said surface area based on the sensed radiation and the detected distance;

means for sensing radiation from the environment incident on said surface area and an electrical circuit for compensating a radiation loss signal for said surface area with the radiation signal for the environment;

a real time clock;

display means responsive to the environment compensated radiation loss signal and the real time clock for providing an illuminated display indicative of the radiation heat loss from said surface area and of the date and time of the measurement; and

means for providing a visual image of the display with the image of the surface area on the photographic film.

17. A method of detecting the radiation heat loss from an extended surface area comprising:

photographing the extended surface area to provide a visual image on a photographic film;

simultaneously sensing the radiation from the surface area by means of a sensing element positioned closely adjacent to the objective of the camera and having a wide field of view of at least about 20°

at any instant substantially matching the field of view of a designated area of the photographic image; and

providing an indication of the sensed radiation on the photographic film.

18. A radiation heat loss detector assembly for providing an indication of the heat loss from an extended surface area comprising:

a wide band, wide field of view thermal radiation sensor for sensing radiation in a field of view of at least about 20°

at any instant;

means for sensing wide band, wide field-of-view radiation from the environment incident on said surface area and an electrical circuit for compensating a radiation signal for said surface area with the radiation signal for the environment to provide a radiation heat loss signal; and

electrically responsive display means for providing a display indicative of the radiation heat loss from said surface area.

19. A radiation heat loss detector assembly as claimed in claim 18 including a single radiation sensor and means electrical circuit for sampling and holding an environmental radiation signal prior to sensing of the surface area radiation.

22. A radiation heat loss detector assembly for providing an indication of the heat loss from an extended surface area comprising:

a camera for providing a visual image of said surface area on photographic film;

a thermal radiation sensor having a field of view of at least about 20°

at any instant substantially matching the field of view of a designated area of the image on the film, the radiation sensor having a wide band response;

sonar means for detecting the distance between the radiation sensor and said surface area;

a real time clock;

display means responsive to the output of the radiation detector, the sonar means and the real time clock for providing an illuminated display indicative of the radiation heat loss from said extended surface area, of the distance between the surface area and the assembly during measurement and of the time of the measurement; and

means for providing a visual image of the display with the image of the surface area on the photographic film.

23. A radiation heat loss detector assembly as claimed in claim 22 further comprising electrical circuit means for compensating a radiation loss signal for said surface area with a radiation signal for the environment and for providing a display of the compensated signal.