Patent Number: 062597574
Section: claims

1. An apparatus for the remote measurement of uranium or plutonium in radioactive materials comprising: a laser which generates a laser beam to produce plasma from a sample;  a measuring head which forms an image of an emission spectrum of plasma produced by the laser beam;  a spectrograph which analyzes the image of the emission spectrum of the plasma formed by the measuring head; and  an analyzing unit which evaluates the emission spectrum of the plasma analyzed by the spectrograph;  wherein said measuring head has a chamber having a bottom that is open ended, said measuring head comprising: 2. An apparatus as set forth in claim 1 characterized in that there is provided a delay unit which delays the beginning of the analyzing procedure relative to the laser pulse emission time. 3. An apparatus as set forth in claim 1 characterized in that the focussing unit has a first lens system. 4. An apparatus as set forth in claim 2 characterized in that the focussing unit has a first lens system. 5. An apparatus as set forth in claims 1, 2, 3 or 4 characterized in that each of the imaging unit has at least a second lens system. 6. An apparatus as set forth in claims 1, 2, 3, or 4 characterized in that said measuring head can be put onto the sample. 7. An apparatus as set forth in claim 5 characterized in that said measuring head can be put onto the sample. 8. An apparatus as set forth in claim 6 characterized in that at said chamber there are arranged a plurality of tubular connecting portions. 9. An apparatus as set forth in claim 7 characterized in that at said chamber there are arranged a plurality of tubular connecting portions. 10. An apparatus as set forth in claim 8 characterized in that the first lens system of the focussing unit is arranged in one of the connecting portions and the second lens system of each imaging unit is arranged in one other connecting portion such that the optical axes of the lens systems pass substantially through a region in space in which the laser-generated plasma of the sample extends. 11. An apparatus as set forth in claim 9 characterized in that the first lens system of the focussing unit is arranged in one of the connecting portions and the second lens system of each imaging unit is arranged in one other connecting portion such that the optical axes of the lens systems pass substantially through a region in space in which the laser-generated plasma of the sample extends. 12. An apparatus as set forth in claim 8 characterized in that provided at the underside of the measuring head is at least one feed conduit through which a flushing fluid is fed to the chamber. 13. An apparatus as set forth in claim 9 characterized in that provided at the underside of the measuring head is at least one feed conduit through which a flushing fluid is fed to the chamber. 14. An apparatus as set forth in claim 10 characterized in that provided at the underside of the measuring head is at least one feed conduit through which a flushing fluid is fed to the chamber. 15. An apparatus as set forth in claim 11 characterized in that provided at the underside of the measuring head is at least one feed conduit through which a flushing fluid is fed to the chamber. 16. An apparatus as set forth in claim 12 characterized in that the flushing fluid is an inert gas. 17. An apparatus as set forth in claim 13 characterized in that the flushing fluid is an inert gas. 18. An apparatus as set forth in claim 14 characterized in that the flushing fluid is an inert gas. 19. An apparatus as set forth in claim 15 characterized in that the flushing fluid is an inert gas. 20. An apparatus as set forth in claim 16 characterized in that the inert gas is argon. 21. An apparatus as set forth in claim 17 characterized in that the inert gas is argon. 22. An apparatus as set forth in claim 18 characterized in that the inert gas is argon. 23. An apparatus as set forth in claim 19 characterized in that the inert gas is argon. 24. An apparatus as set forth in claim 3 characterized in that for coupling the first light guide to the laser there is provided a light guide coupling-in unit which is releasably fixed to the housing of the laser so as to avoid disadjustment of the light guide relative to the laser beam. 25. An apparatus as set forth in claim 4 characterized in that for coupling the first light guide to the laser there is provided a light guide coupling-in unit which is releasably fixed to the housing of the laser so as to avoid disadjustment of the light guide relative to the laser beam. 26. An apparatus as set forth in claim 24 characterized in that the light guide coupling-in unit has a light guide connection and a laser beam introduction opening wherein the light guide connected to the light guide connection for adjustment relative to the laser beam introduction opening is pivotable about its two mutually orthogonal transverse axes: y, z and is linearly displaceable in the direction of the transverse axes: y, z and in the direction of its longitudinal axis, x. 27. An apparatus as set forth in claim 25 characterized in that the light guide coupling-in unit has a light guide connection and a laser beam introduction opening wherein the light guide connected to the light guide connection for adjustment relative to the laser beam introduction opening is pivotable about its two mutually orthogonal transverse axes: y, z and is linearly displaceable in the direction of the transverse axes: y, z and in the direction of its longitudinal axis, x. 28. An apparatus as set forth in claim 1 characterized in that the first light guide is a glass fiber or a glass fiber cable. 29. An apparatus as set forth in claim 1 characterized in that the second light guides are glass fiber or glass fiber cables.