Methods of using laser optical devices

1. A method of spatially detecting the chemical composition of nonmetallic components on a surface which is subsequently to be coated with a metallic and/or ceramic and/or organic layer, the method comprising:

providing a laser optical device;

irradiating the surface with monochromatic irradiation at a first wavelength (λ in ) with said laser optical device;

detecting radiation emitted by said surface at a second wavelength (λ out ) which is longer than the first wavelength (λ in ) with a detector such that the laser optical device and the detector are maintained at a targeted spatial position; and

determining, based on said detecting, a spatial position of said nonmetallic components relative to at least one of said laser optical device and said detector.

2. The method as claimed in claim 1 , wherein providing comprises providing a Raman spectrometer.

3. The method as claimed in claim 2 , wherein detecting comprises determining organic and/or inorganic contaminations and/or residues on said surface with said Raman spectrometer.

4. The method as claimed in claim 1 , wherein providing comprises providing a fluorescence spectrometer.

5. The method as claimed in claim 4 , wherein detecting comprises determining the presence of aluminum oxide on the surface with said fluorescence spectrometer.

6. The method as claimed in claim 1 , wherein providing comprises providing a Raman spectrometer and a fluorescence spectrometer.

7. The method as claimed in claim 6 , wherein detecting comprises determining the presence of aluminum oxide on the surface with said fluorescence spectrometer.

8. The method as claimed in claim 1 , wherein irradiating comprises systematically guiding the laser optical device over the surface, and further comprising:

processing correspondingly spatially resolved data from said detecting to form a surface image.

9. The method as claimed in claim 8 , wherein processing comprises processing data from a Raman spectrometer and from a fluorescence spectrometer, or from a combined Raman/fluorescence spectrometer, in a combined way to form a surface image.

10. The method as claimed in claim 1 , wherein:

irradiating comprises directing input radiation onto an area having a length in the range of 10-100 μm each spatial direction; and

detecting comprises collimating and analyzing radiation emitted by the surface with respect to the frequencies and/or intensities contained in said radiation, in order to generate a surface image.

11. The method as claimed in claim 1 , wherein:

irradiating comprises defocusing said monochromatic irradiation onto an area having a length in the range of 1-20 mm in each spatial direction; and

detecting comprises collimating and analyzing radiation emitted by the surface with respect to the frequencies and/or intensities contained in said radiation, in order to generate a surface image.

12. The method as claimed in claim 1 , wherein:

said laser optical device comprises at least one optical fiber; and

said irradiating, said detecting, or both are carried out with said least one optical fiber.

13. The method as claimed in claim 12 , wherein the same optical fiber is used for said irradiating and said detecting.

14. The method as claimed in claim 1 , wherein the surface comprises the surface of a turbine part.

15. The method as claimed in claim 1 , wherein the surface comprises the surface of a gas turbine part made of a metallic material.

16. The method as claimed in claim 1 , wherein the surface comprises the surface of a gas turbine part made of a refractory material.

17. The method as claimed in claim 16 , in which said gas turbine part has previously been cast or forged, and wherein the refractory material has previously undergone a surface treatment selected from the group consisting of sandblasting, washing, etching, plasma treatment, coating, and combinations thereof.