Methods and devices for sensing temperature and oxygen pressure with a single optical probe

An arrangement for measuring the temperature of an object or environment, comprising

• a) a probe in thermal communication with said object or environment, said probe including a photoluminescent material so characterized that, when illuminated at any temperature within the temperature range of application of the arrangement with a first excitation light of intensity P1 and pre-selected wavelength or wavelengths λ1, it emits a first luminescence light of intensity I1, and when illuminated with a second excitation light of intensity PT and pre-selected wavelength or wavelengths λv, it emits a second luminescence light of intensity IT, the relative responses of the luminescence intensities IT and I1 to a temperature change being such that the ratio (IT·P1/I1·PT) increases substantially in a known manner with increasing temperature;
• b) first light source means for illuminating said material with said first excitation light of said wavelength or wavelengths λ1 and intensity P1, and thus generating a first luminescence light emitted by the probe with said intensity I1;
• c) second light source means for illuminating said material with said second excitation light of an intensity PT and wavelength or wavelengths λv, thereby generating a second luminescence light emitted by the probe having an intensity IT;
• d) optical means for directing a fraction of said intensity I1 of said first luminescence light to photodetector means;
• e) optical means for directing a fraction of said intensity IT of said second luminescence light to photodetector means;
• and
• f) photodetector and associated electronic means for measuring the relative intensities of the luminescence lights generated by said first and said second excitation lights received by said photodetector means, said relative intensities being an indicator of the temperature being measured.

An arrangement for measuring the temperature distribution on a surface covered by a photoluminescent paint, comprising

• a) first light source means for illuminating a selected area of said paint, said area comprising a multiplicity of resolvable smaller areas, with a first excitation light of wavelength or wavelengths λ1 and intensity P1, so chosen that it generates a luminescence image at said selected area, said image comprised of the luminescence intensities I1 of each and all said smaller areas;
• b) optical means for focusing and storing said luminescence image on a video image device;
• c) second light source means for illuminating said selected area of said paint with said second excitation light of an intensity PT and wavelength or wavelengths λv so chosen that it generates a luminescence image at said selected area, said image comprised of the luminescence intensities IT of each and all said smaller areas, the intensity at any of said smaller areas being related to the luminescence intensity I1 at the same smaller area in such a manner that the ratio (IT·P1/I1·PT) increases substantially in a known manner with increasing temperature;
• substantially independent of any air pressure then acting on the paint or of any thickness inhomogeneities on the paint;
• d) optical means for focusing and storing said luminescence image generated by said second excitation light on a video image device;
• e) electronic means for computing said ratio (IT·P1/I1·PT) for each and all said resolvable smaller areas and thus determining the temperature distribution at said surface.