Patent · US Expired

Surface photothermic testing device

US5803606A · kind A · utility

16Cited by
14References
2Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 8, 1996
Grant dateSep 8, 1998
Priority date
Expiry dateMay 8, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N25/72
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

In a device for photothermically testing a surface (1) of a moving test specimen (2), an excitation beam (5) may be applied to a test area (13). The excitation beam (5) passes through an aperture (12) in a collecting lens (11) that reproduces the thermal radiation generated in a measuring area (14), so that the collecting lens (11) may be adapted to a wavelength of the excitation beam (5) passed to a detector (20). A coupling mirror (9) mounted in the path of excitation beam (5) has practically total reflectivity for the wavelength of the excitation beam (5) and is arranged in such a way that it is very small near the focal area of the excitation beam (5), so that together with the aperture (12) of the collecting lens (11) it only masks a small part of the thermal radiation (17) passed to the detector (20). In another embodiment, the excitation beam (5) falls directly on the surface (1) through an aperture in the decoupling mirror that deflects the thermal radiation, whereas the thermal radiation can be passed with practically all is intensity to the detector (20) through the decoupling mirror with appropriate reflectivity.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.