Radiant energy – Invisible radiant energy responsive electric signalling – Infrared responsive
Patent
1993-09-15
1994-12-27
Hannaher, Constantine
Radiant energy
Invisible radiant energy responsive electric signalling
Infrared responsive
250330, 250332, G01N 2184, G01N 2500
Patent
active
053767934
ABSTRACT:
An instrument employs a projector which projects a moving pattern of heat onto a test object. An exemplary pattern is formed of bars or lines of infrared radiation separated by unheated areas, or areas of shadow. An infrared camera which is not sensitive to the wave-length of the projected light is used to detect the heat emitted by the test object. The projected bands of thermal radiation heat the surface of the test object. Some of the energy in the form of heat sinks into the structure, while some of the heat energy flows laterally from the heated band to the unheated bands between the projected bands. The lateral flow of heat between bands is resisted by cracks in the surface. This resistance causes heat energy to build up on one side of each crack. The downward flow of heat energy is resisted by less conductive material such as a debonding between layers which traps the heat, causing it to build up laterally. Thus, flaws caused by cracks normal to the surface and delaminations or cracks parallel to the surface may be detected by the same device.
REFERENCES:
patent: 4172382 (1979-10-01), Murphy et al.
patent: 4184768 (1980-01-01), Murphy et al.
patent: 4468136 (1984-08-01), Murphy et al.
patent: 4589783 (1986-05-01), Thomas et al.
patent: 4724482 (1988-02-01), Duvent
patent: 4798477 (1989-01-01), Mountain
patent: 4854724 (1989-08-01), Adams et al.
patent: 4866276 (1989-09-01), Leavens et al.
patent: 4874251 (1989-10-01), Thomas et al.
patent: 4878116 (1989-10-01), Thomas et al.
patent: 4886370 (1989-12-01), Koshihara et al.
patent: 4968144 (1990-11-01), Thomas et al.
patent: 4983836 (1991-01-01), Matoba et al.
patent: 5012112 (1991-04-01), Flint et al.
patent: 5111048 (1992-05-01), Devitt et al.
patent: 5118945 (1992-06-01), Winschuh et al.
patent: 5201582 (1993-04-01), Lesniak
patent: 5208766 (1993-05-01), Chang et al.
patent: 5292195 (1994-03-01), Crisman, Jr.
Cramer, et al. "Thermographic Imaging of Cracks in Thin Metal Sheets," 162/SPIE vol. 1682 Thermosense XIV. 0-8194-0843-3/92/$4.00.
Favro et al., "Intersion of pulsed thermal-wave images for defect sizing and shape recovery," 178/SPIE vol. 1682 Thermosense XIV. 0-8194-0843-3/92/$4.00.
Spicer et al., "Source patterning in time-resolved infrared radiometry (TRIR) of composite structures," 248/SPIE vol. 1682 Thermosense XIV. 0-8194-0843-3/92/$4.00.
Glick Edward J.
Hannaher Constantine
Stress Photonics Inc.
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