Analytical instruments using a pseudorandom array of sources, such as a micro-machined mass spectrometer or monochromator

• US 20050119868A1
• Filed: 02/20/2003
• Published: 06/02/2005
• Est. Priority Date: 02/20/2002
• Status: Active Grant

• Current Assignee: University of Washington
• Original Assignee: University of Washington
• Inventors: Hess, Henry, Scheidemann, Adi
• Granted Patent: US 7,339,521 B2
• Time in Patent Office: Days
• US Class Current: 702/196
• CPC Class Codes: H01J 49/107 Arrangements for using several ion sources

Abstract

Novel methods and structures are disclosed herein which employ pseudorandom sequences to spatially arrange multiple sources in a pseudorandom source array. The pseudorandom source array can replace the single source in analytical instruments relying on spatial separation of the sample or the probe particles/waves emitted by the sources. The large number of sources in this pseudorandom source array enhances the signal on a position sensitive detector. A mathematical deconvolution process retrieves a spectrum with improved signal-to-noise ratio from the detector signal.

Claims

1. An assembly for use in an analytical device, comprising a plurality of sources, the sources spatially arrayed pseudorandomly in at least a first dimension.

2. The assembly of claim 1 wherein there are 2n−

1 sources arranged in a pseudorandom sequence of a length equal to 2n−

1.

3. The assembly of claim 1 wherein each of the plurality of sources is one of an electromagnetic radiation emitting source, an ion emitting source and a sound emitting source.

4. The assembly of claim 1 wherein each of the plurality of sources are formed on a common substrate.

5. The assembly of claim 1 wherein each of the plurality of sources are micro-machined structures on a common substrate.

6. The assembly of claim 1 wherein the plurality of sources are arranged about a closed surface.

7. The assembly of claim 1 wherein the plurality of sources are arranged about a circle.

8. The assembly of claim 1 wherein the plurality of sources are spatially arrayed pseudorandomly in at least a second dimension.

9. The assembly of claim 1 wherein the plurality of sources are spatially arrayed pseudorandomly by a respective pseudorandom number of blanks between each respective pair of the sources in the array.

10. An analytical device, comprising:

a source assembly comprising a plurality of sources, the sources spatially arrayed pseudorandomly in at least a first dimension; and

a detector assembly spaced from the source assembly, the detector assembly comprising a number of sensors sensitive to an output of the plurality of sources.

11. The analytical device of claim 10 wherein the detector comprises an array of photosensitive sensors.

12. The analytical device of claim 10 wherein the detector comprises an array of photosensitive charge coupled devices.

13. The analytical device of claim 10 wherein the detector comprises an array of Faraday cups.

14. The analytical device of claim 10 wherein the number of sensors in the detector assembly is less than a number of sources in the source assembly.

15. The analytical device of claim 10 wherein the number of sensors in the detector assembly is equal to N+L−

1 where N is the number of sources and L is the length of a spectrum.

16. The analytical device of claim 10 wherein the plurality of sources and the number of sensors arranged about respective concentric circles.

17. An analytical device, comprising:

a source assembly comprising a plurality of sources, the sources spatially arrayed pseudorandomly in at least a first dimension;

a detector assembly spaced from the source assembly, the detector assembly comprising a number of sensors sensitive to an output of the plurality of sources; and

a dispersion element positioned in a path between at least one of the plurality of sources and at least one of the sensors to disperse the output of at least one of the plurality of sources.

18. The analytical device of claim 17 wherein the dispersion element comprises a magnetic assembly positioned to create a magnetic field in the path between at least one of the plurality of sources and at least one of the sensors to disperse the output of at least one of the plurality of sources.

19. The analytical device of claim 17 wherein the dispersion element comprises a prism positioned in the path between at least one of the plurality of sources and at least one of the sensors to disperse the output of at least one of the plurality of sources according to wavelength.

20. The analytical device of claim 17 wherein the dispersion element comprises a grating positioned in the path between at least one of the plurality of sources and at least one of the sensors to disperse the output of at least one of the plurality of sources according to wavelength.

21. The analytical device of claim 17 wherein the dispersion element comprises a sample is positioned in the path between at least one of the plurality of sources and at least one of the sensors to disperse the output of at least one of the plurality of sources during use.

22. The analytical device of claim 17 in the form of one of a mass spectrometer wherein the each of the plurality of sources are ion emitters, the dispersing element is a magnetic assembly and the sensors of the detector assembly is an array of Faraday cups.

23. The analytical device of claim 17 in the form of a monochromator wherein the plurality of sources is an array of entrance slits, the dispersing element is a grating, and the detector assembly is an array of charge coupled devices.

24. The analytical device of claim 17 in the form of a computer aided tomography scanner wherein the plurality of sources are X-ray emitting sources, the dispersing element is a sample being analyzed, and the sensors of the detector assembly are X-ray detectors.

25. The analytical device of claim 17 in the form of a magnetic resonance imager wherein the plurality of sources are radio frequency emitters, the dispersing element is a sample being analyzed, and the sensors of the detector assembly are magnetic coils.

26. The analytical device of claim 17 in the form of a ultrasound machine wherein the plurality of sources are speakers, the dispersing element is a sample being analyzed, and the sensors of the detector assembly are ultrasonic transducers.

27. An analytical system, comprising:

a source assembly comprising a plurality of sources, the sources spatially arrayed pseudorandomly in at least a first dimension;

a detector assembly spaced from the source assembly, the detector assembly comprising a number of sensors sensitive to an output of the plurality of sources; and

a computer coupled to the detector assembly to receive detector signals therefrom corresponding to the output of the plurality of sources sensed by the number of sensors, the computer programmed to process the detector signals via a deconvolution algorithm.

28. The analytical system of claim 27 wherein the computer is programmed to process the detector signals via a deconvolution algorithm by:

constructing a detector signal matrix from the detector signals;

multiplying the detector signal matrix by a deconvolution matrix to produce a spectrum matrix; and

truncating the spectrum matrix after the first L elements to produce a pseudorandom spectrum.

29. The analytical system of claim 27 wherein the number of sensors in the detector assembly is equal to N+L−

1 where N is the number of sources and L is the length of a spectrum.

30. An analytical system, comprising:

a source assembly comprising a plurality of sources spatially arrayed in at least a first dimension;

a detector assembly spaced from the source assembly, the detector assembly comprising a number of sensors sensitive to an output of the plurality of sources; and

a computer coupled to control activation of the sources in a spatially pseudorandom order in at least a first dimension.

31. The analytical system of claim 30 wherein the plurality of sources are spatially arrayed uniformly in the first dimension.

32. The analytical system of claim 30 wherein the computer is coupled to control activation of the sources in a spatially pseudorandom order in at least a first dimension by:

activating successive ones of the plurality of sources with a respective pseudorandom number of unactivated sources between each respective pair of the activated sources in the array.

33. A method of operating an analytical device, comprising:

activating a number of pseudorandomly arrayed sources to produce output;

detecting output produced by the pseudorandomly arrayed sources;

producing detector signals corresponding to the detected output; and

deconvoluting the detector signals to produce a pseudorandom spectrum.

34. The method of claim 33 wherein deconvoluting the detector signals to produce a pseudorandom spectrum, comprises:

constructing a detector signal matrix from the detector signals;

multiplying the detector signal matrix by a deconvolution matrix to produce a spectrum matrix; and

truncating the spectrum matrix after the first L elements to produce a pseudorandom spectrum.

35. The method of claim 33 wherein activating a number of pseudorandomly arrayed sources produce output comprises emitting electromagnetic radiation from each of a number of the plurality of source.

36. The method of claim 33 wherein activating a number of pseudorandomly arrayed sources to produce output comprises emitting ions from each of a number of the plurality of sources.

37. The method of claim 33 wherein activating a number of pseudorandomly arrayed sources to produce output comprises emitting samples from each of a number of the plurality of sources.

38. The method of claim 33 wherein activating a number of pseudorandomly arrayed sources to produce output comprises emitting sound from each of a number of the plurality of sources.

39. The method of claim 33 wherein detecting output produced by the pseudorandomly arrayed sources comprises detecting light at an array of spaced photosensitive sensors.

40. The method of claim 33 wherein detecting output produced by the pseudorandomly arrayed source elements comprises detecting ions at an array of spaced Faraday cups.

41. The method of claim 33 wherein detecting output produced by the pseudorandomly arrayed source elements comprises detecting ultrasonic vibration at an array of audio transducers.

42. The method of claim 33, further comprising:

dispersing the output of the source elements via a sample before detecting the output of the source elements.

43. The method of claim 33, further comprising dispersing the output of the source elements via a grating before detecting the output of the source elements.

44. The method of claim 33, further comprising dispersing the output of the source elements via a magnetic field before detecting the output of the source elements.

45. A method of operating an analytical device comprising activating a number of the plurality of sources in succession, where successive ones of the activated sources are separated from one another by a respective pseudorandom number of the sources;

detecting output produced by the pseudorandomly arrayed sources; and

producing detector signals corresponding to the detected output.

46. The method of claim 45, further comprising:

deconvoluting the detector signals to produce a pseudorandom spectrum.

47. An analytical device, comprising:

means for activating a number of pseudorandomly arrayed sources to produce output;

a detector coupled to detect output produced by the pseudorandomly arrayed sources and to produce detector signals corresponding to the detected output; and

means for deconvoluting the detector signals to produce a pseudorandom spectrum.

48. The device of claim 47 wherein the means for deconvoluting comprises computing means for:

constructing a detector signal matrix from the detector signals;

multiplying the detector signal matrix by a deconvolution matrix to produce a spectrum matrix; and

truncating the spectrum matrix after the first L elements to produce a pseudorandom spectrum.

49. A cryptographic device, comprising:

a source assembly comprising a plurality of sources, the sources spatially arrayed pseudorandomly in at least a first dimension;

a transmission channel the detector assembly is an array of charge coupled devices; and

a grating positioned in a path between at least one of the plurality of sources and at least one of the sensors to disperse the output of at least one of the plurality of sources.

50. The cryptographic device of claim 49 wherein the transmission channel comprises a plurality of optical fibers, each of the optical fibers having a first end positioned to receive a respective wavelength of light diffracted from the grating.

51. The cryptographic device of claim 49 wherein the plurality of sources is an array of entrance slits.