Raman spectroscope

• US 20050128476A1
• Filed: 12/16/2003
• Published: 06/16/2005
• Est. Priority Date: 12/16/2003
• Status: Active Grant

• Current Assignee: Bruker Optics, Inc. (Bruker Corporation)
• Original Assignee: New Chromex, Inc.
• Inventors: Zhao, Jun
• Granted Patent: US 7,102,746 B2
• Time in Patent Office: Days
• US Class Current: 356/301
• CPC Class Codes: G01J 3/0291 Housings; Spectrometer accessories; Spatial arrangement of elements, e.g. folded path arrangements
• CPC Class Codes: G01J 3/44 Raman spectrometry; Scattering spectrometry ; Fluorescence spectrometry
• CPC Class Codes: G01N 2021/656 Raman microprobe
• CPC Class Codes: G01N 21/65 Raman scattering

Abstract

A compact spectroscope is sufficiently lightweight for use in combination with a microscope for analyzing samples using Raman analytical techniques. The Raman spectroscope includes a housing detachably mountable to the microscope. The housing contains at least one source of radiation. One or more filters are positioned at desired angles across the beam path provided by the source of radiation. The spectroscope includes a variety of components operatively connected to source of radiation capable of providing one or more Raman beams, as well as a variety of components for processing beam constituents for microscope analysis. A fiber optic probe is provided for examining large samples or samples at remote sites. A computer or other electronic reader may also be attached to the Raman spectroscope for viewing analytical data.

Claims

1. A Raman spectroscope attachment, comprising:

a spectral analysis apparatus,

wherein the spectral analysis apparatus is detachably mountable on a microscope.

2. A Raman spectroscope attachment as recited in claim 1, further comprising a source of radiation installed in the spectral analysis apparatus for providing at least one excitation beam.

3. A Raman spectroscope attachment as recited in claim 1, wherein the microscope includes at least one objective lens.

4. A Raman spectroscope attachment as recited in claim 1, further comprising a beam-combining module mountable in the path of the at least one excitation beam installed in the spectral analysis apparatus for directing an excitation beam to the at least one objective lens.

5. A Raman spectroscope attachment as recited in claim 1, further comprising means for focusing the excitation beam on a sample and for collecting Raman data from the sample.

6. A Raman spectroscope attachment as recited in claim 1, wherein the source of radiation is monochromatic.

7. A Raman spectroscope attachment as recited in claim 1, wherein the spectral analysis apparatus includes a spectral analyzer.

8. A Raman spectroscope attachment as recited in claim 1, wherein the spectral analysis apparatus includes a detector.

9. A Raman spectroscope attachment as recited in claim 1, wherein the spectral analysis apparatus includes one or more optical devices.

10. A Raman spectroscope attachment as recited in claim 1, wherein the Raman spectroscope attachment further comprises at least one electronic device for viewing compiled data.

12. A Raman spectroscope attachment as recited in claim 4, wherein the beam-combining module is selected from the group of beam-combining modules consisting of dichroic mirrors, mirrors provided with one or more holes, beam splitters, holographic filters, and interference filters.

13. A Raman spectroscope attachment as recited in claim 12, wherein the beam-combining module includes means for redirecting a scattered Raman beam into the Raman spectral analysis apparatus, and further wherein the beam-combining module directs the excitation beam through the objective lens.

14. A Raman spectroscope attachment as recited in claim 1, wherein the spectral analysis apparatus further comprises at least one Rayleigh rejection filter.

15. A Raman spectroscope attachment as recited in claim 14, wherein the at least one Rayleigh rejection filter is selected from the group of filters consisting of interference filters, edge filters, rugate filters, and holographic filters.

16. A Raman spectroscope attachment as recited in claim 15, wherein the at least one Rayleigh rejection filter is capable of reflecting the at least one excitation beam while passing the Raman scattered beam.

17. A Raman spectroscope attachment as recited in claim 16 wherein the at least one Rayleigh rejection filter is oriented at an angle across the path of the at least one excitation beam at substantially less than 45 degrees.

18. A Raman spectroscope, comprising:

a Raman spectral analysis apparatus that includes a source of radiation,

wherein the spectral analysis apparatus is detachably mountable on a microscope; and

at least one interference filter installable in the Raman spectral analysis apparatus,

wherein the at least one interference filter is adjustably positionable within a range of predetermined angles.

19. A Raman spectroscope as recited in claim 18, wherein the source of radiation is monochromatic.

20. A Raman spectroscope as recited in claim 18, wherein the spectral analysis apparatus includes a spectral analyzer.

21. A Raman spectroscope as recited in claim 18, wherein the spectral analysis apparatus includes a detector.

22. A Raman spectroscope as recited in claim 18, wherein the spectral analysis apparatus includes one or more optical devices.

23. A Raman spectroscope as recited in claim 18, wherein the Raman spectroscope further comprises at least one fiber optic probe.

24. A Raman spectroscope as recited in claim 18, wherein the Raman spectroscope further comprises at least one electronic device for viewing analysis data.

25. A Raman spectroscope as recited in claim 18, wherein the interference filter is an edge filter.

26. A Raman spectroscope as recited in claim 18, wherein the at least one interference filter is a rugate filter.

27. A Raman spectroscope as recited in claim 18, wherein the at least one interference filter is adjustable within a range from 0 degrees to 10 degrees.

28. A spectroscope system, comprising:

an infinity corrected light microscope for analyzing a sample;

a housing detachably mountable on the microscope;

at least one source of radiation positionable in the housing for producing one or more beam paths; and

means operatively connectable to the at least one source of radiation for analyzing Raman spectra from the one or more beam paths,

wherein the Raman spectra analyzing means includes one or more filters.

29. A spectroscope system as recited in claim 28, further comprising a fiber optic probe demountably attachable to the housing for examining samples.

30. A spectroscope system as recited in claim 29, wherein the one or more Raman beams analyzing means includes a spectral analyzer.

31. A spectroscope system as recited in claim 30, wherein the spectral analyzer is selected from the group of spectral analyzers consisting of dispersive analyzers, Fourier Transform analyzers, interferometers, and tunable filters.

32. A spectroscope system as recited in claim 31, wherein the one or more Raman beams analyzing means includes a detector.

33. A spectroscope system as recited in claim 32, wherein the one or more filters is an edge filter.

34. A spectroscope system as recited in claim 33, wherein the one or more filters is a rugate filter.

35. A spectroscope system as recited in claim 34, wherein the one or more filters is positionable in relationship to the beam path at an angle ranging from 0 degrees to 10 degrees.

36. A spectroscope as system as recited in claim 35, further comprising means for detachably mounting the housing to the microscope.

37. A spectroscope system as recited in claim 36, wherein the microscope mounting means are selected from the group of mounting means consisting of reciprocal dovetail connections, slides, slots, locks, clamps, nuts, bolts, and connectors.

38. A method of manufacturing a compact spectrometer for a microscope, comprising:

providing a source of incident radiation for analyzing constituents of a sample;

selecting low costs, light weight, small mass components for directing the incident radiation through the compact spectrometer;

equipping the compact spectrometer with one or more interference filters;

including in the compact spectrometer a spectral analyzer;

positioning in the compact spectrometer a detector; and

disposing one or more fiber optic probes demoutably attachable to the compact spectrometer for analyzing alternative samples.

39. A method of manufacturing a compact spectrometer for a microscope as recited in claim 38, wherein the source of incident radiation providing step includes the substep of providing at least one diode laser to enhance compactness of the compact spectrometer.

40. A method of manufacturing a compact spectrometer for a microscope as recited in claim 38, wherein the source of incident radiation providing step includes the substep of providing a beam path through the compact spectrometer.

41. A method of manufacturing a compact spectrometer for a microscope as recited in claim 38, wherein the one or more interference filters equipping step includes the substeps of selecting the one or more interference filters from the group of interference filters consisting of edge filters and rugate filters.

42. A method of manufacturing a compact spectrometer for a microscope as recited in claim 38, one or more interference filters equipping step includes the substep of positioning the one or more interference filters at an angle to the beam path ranging from 0 degrees to 10 degrees.

43. A method of manufacturing a compact spectrometer for a microscope as recited in claim 38, one or more interference filters equipping step includes the substep of positioning the one or more interference filters at an angle to the beam path ranging from 0 degrees to 15 degrees.

44. A method of manufacturing a compact spectrometer for a microscope as recited in claim 38, wherein the spectral analyzer including step includes the substeps of:

including one or more dispersive analyzers;

including one or more FT-Raman analyzers;

including one or more interferometers; and

/or including one or more tunable filters.

45. A method for introducing an excitation beam into a Raman beam path, comprising the steps of:

providing an interference filter;

directing the excitation beam toward the filter at a low incident angle;

reflecting from the interference filter the majority of the excitation mean intensity in the form of a reflected excitation beam;

directing the Raman beam toward the interference filter in the opposite but parallel direction of the reflected excitation beam;

reflecting a majority of a Raleigh scattered component of the Raman beam; and

transmitting a majority of the Raman scattered component for analysis.

46. A method for introducing an excitation beam into a Raman beam path as recited in claim 45, wherein the interference filter is an edge filter.

47. A method for introducing an excitation beam into a Raman beam path as recited in claim 46, wherein the interference filter is a rugate filter.

48. A method for introducing an excitation beam into a Raman beam path, comprising the steps of:

providing an optical filter;

directing the excitation beam toward the optical filter at a low incident angle;

transmitting through the optical filter the majority of the excitation mean intensity in the form of a transmitted excitation beam;

directing the Raman beam toward the optical filter in the opposite but parallel direction of the transmitted excitation beam;

transmitting further a majority of a Raleigh scattered component of the Raman beam; and

reflecting a majority of the Raman scattered component for analysis.

49. A method for introducing an excitation beam into a Raman beam path as recited in claim 48, wherein the optical filter is selected from the group of filters consisting of interference filters, edge filters, rugate filters, and holographic filters.