Methods for characterizing gems or precious stones using a probe having a plurality of light receivers

• US 6,958,810 B2
• Filed: 06/02/2003
• Issued: 10/25/2005
• Est. Priority Date: 06/30/1998
• Status: Expired due to Term

• Current Assignee: RPX Corporation
• Original Assignee: JJL Technologies, L.L.C.
• Inventors: Jung, Wayne D, Jung, Russell W., Loudermilk, Alan R.
• Primary Examiner(s): Toatley, Jr., Gregory J.
• Assistant Examiner(s): MERLINO, AMANDA H
• Application Number:
  US10/453,832
• Publication Number:
  US 20030197855A1
• Time in Patent Office: 876 Days
• Field of Search: 356/73, 356445-446, 356416-420
• US Class Current: 356/73
• CPC Class Codes: A61B 5/0088 for oral or dental tissue
• CPC Class Codes: G01J 2003/1217 Indexed discrete filters or choppers
• CPC Class Codes: G01J 2003/1234 Continuously variable IF [CVIF]; Wedge type
• CPC Class Codes: G01J 2003/468 of objects containing fluorescent agent
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0208 using focussing or collimating elements, e.g. lenses or mirrors; performing aberration correction
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/0229 using masks, aperture plates, spatial light modulators or spatial filters, e.g. reflective filters
• CPC Class Codes: G01J 3/0264 Electrical interface; User interface
• CPC Class Codes: G01J 3/0272 Handheld
• CPC Class Codes: G01J 3/0278 Control or determination of height or angle information for sensors or receivers
• CPC Class Codes: G01J 3/0283 using a charging unit
• CPC Class Codes: G01J 3/0291 Housings; Spectrometer accessories; Spatial arrangement of elements, e.g. folded path arrangements
• CPC Class Codes: G01J 3/463 Colour matching
• CPC Class Codes: G01J 3/508 measuring the colour of teeth
• CPC Class Codes: G01J 3/51 using colour filters
• CPC Class Codes: G01J 3/513 having fixed filter-detector pairs
• CPC Class Codes: G01J 3/524 Calibration of colorimeters
• CPC Class Codes: G01N 21/251 Colorimeters; Construction thereof
• CPC Class Codes: G01N 21/474 Details of optical heads therefor, e.g. using optical fibres
• CPC Class Codes: G01N 21/57 : Measuring gloss

Abstract

Optical characteristic measuring systems and methods such as for determining the color or other optical characteristics of teeth are disclosed. Perimeter receiver fiber optics are spaced apart from a source fiber optic and receive light from the surface of the object/tooth being measured. Light from the perimeter fiber optics pass to a variety of filters. The system utilizes the perimeter receiver fiber optics to determine information regarding the height and angle of the probe with respect to the object/tooth being measured. Under processor control, the optical characteristics measurement may be made at a predetermined height and angle. Various color spectral photometer arrangements are disclosed. Translucency, fluorescence, gloss and/or surface texture data also may be obtained. Audio feedback may be provided to guide operator use of the system. The probe may have a removable or shielded tip for contamination prevention. A method of producing dental prostheses based on measured data also is disclosed. Measured data also may be stored and/or organized as part of a patient data base.

Claims

1. A method for characterizing a gem or precious stone comprising the steps of:

positioning a probe and the gem or precious stone to be in proximity with respect to each other, wherein the probe provides light to the gem or precious stone from one or more light sources, and receives light from the gem or precious stone through a plurality of light receivers, wherein the plurality of light receivers comprise one or more first light receivers and one or more second light receivers, wherein the one or more first light receivers have a first numerical aperture and the one or more second light receivers have a second numerical aperture different from the first numerical aperture;

determining the intensity of light received by more than one of the light receivers; and

measuring the optical characteristics of the gem or precious stone, wherein the measurement produces data indicative of the optical characteristics of the gem or precious stone.

2. The method of claim 1, wherein

wherein each of the plurality of light receivers has a spacing from the one or more light sources, wherein for each of the plurality of light receivers a critical height is defined,

wherein, when the probe is a distance from the gem or precious stone that is less than the critical height for a particular light receiver, light that is reflected from the surface of the gem or precious stone is not received by the particular light receiver,

wherein the one or more first light receivers have at least a first critical height and the one or more second light receivers have at least a second critical height different from the first critical height.

3. The method of claim 1, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers determines a height or angle of the probe with respect to the gem or precious stone.

4. The method of claim 1, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers determines a height and angle of the probe with respect to tho gem or precious stone.

5. The method of claim 1, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers determines a height or angle of the probe with respect to the gem or precious stone, wherein the optical characteristics measurement is compensated based on data indicative of the height or angle of the probe with respect to the gem or precious stone.

6. The method of claim 1, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers determines a height or angle of the probe with respect to the gem or precious stone, wherein the optical characteristics measurement is selectively rejected based on data indicative of the height or angle of the probe with respect to the gem or precious stone.

7. The method of claim 1, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers couple received light to a color measuring spectrometer.

8. The method of claim 1, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers couple received light to a colorimeter.

9. The method of claim 1, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers couple received light to one or more light sensors that output a signal with a frequency that increases with an intensity of received light.

10. The method of claim 9, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers couple received light to one or more light sensors that output a signal with a frequency that increases with an intensity of received light, wherein the light passes through at least one filter element before being coupled to the one or more light sensors.

11. The method of claim 10, wherein the at least one filter element comprises an interference filter.

12. The method of claim 10, wherein the at least one filter element comprises a color gradient filter.

13. The method of claim 10, further comprising the step of measuring a temperature, wherein the optical characteristics measurement is based on the temperature measurement.

14. The method of claim 9, wherein the method further comprises coupling bias light to the one or more light sensors.

15. The method of claim 1, wherein the first and second light receivers comprise a plurality of receivers having differing diameters.

16. The method of claim 1, wherein at least one of the one or more first light receivers or at least one of the one or more second light receivers couple received light to a matrix optical sensor.

17. The method of claim 16, wherein the light is coupled to the matrix optical sensor via a filter element.

18. The method of claim 17, wherein the filter element comprises a color gradient filter.

19. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes a color measurement and a measurement of translucence.

20. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes a color measurement and a measurement of gloss.

21. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes a color measurement and a measurement of fluorescence.

22. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes a color measurement and a measurement of opalescence.

23. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes a color measurement and a measurement of surface texture.

24. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes a color measurement and a measurement of translucence, gloss, fluorescence, opalescence and/or surface texture, wherein the color measurement is a function of the measurement of translucence, gloss, fluorescence, opalescence and/or surface texture.

25. The method of claim 1, wherein the one or more first light receivers and the one or more second light receivers couple received light to a plurality of light sensors, wherein the light sensors comprise at least a first sensor implement that measures received light in a plurality of spectral bands each having a wavelength, wherein the light sensors also comprise at least a second sensor implement that measures received light in a single spectral band.

26. The method of claim 25, wherein the single spectral band is broader in wavelength as compared to the wavelength of each of the plurality of spectral bands.

27. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone generates data indicative of a subsurface characteristic of the gem or precious stone.

28. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone generates data indicative of a surface spectral reflectance response and a bulk spectral response.

29. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes measurements taken at two more distances of the probe with respect to a surface of the gem or precious stone, wherein data is generated that are indicative of an opalescence characteristic of the gem or precious stone.

30. The method of claim 1, wherein the probe is covered by a removable tip.

31. The method of claim 1, wherein

wherein each of the plurality of light receivers has a spacing from the one or more light sources, wherein for each of the plurality of light receivers a critical height is defined,

wherein, when the probe is a distance from the gem or precious stone that is less than the critical height for a particular light receiver, light that is reflected from the surface of the gem or precious stone is not received by the particular light receiver,

wherein the one or more first light receivers have at least a first critical height and the one or more second light receivers have at least a second critical height different from the first critical height,

wherein the probe is covered by a removable tip that has a thickness less than the first critical height or the second critical height.

32. The method of claim 1, wherein

wherein each of the plurality of light receivers has a spacing from the one or more light sources, wherein for each of the plurality of light receivers a critical height is defined,

wherein, when the probe is a distance from the gem or precious stone that is less than the critical height for a particular light receiver, light that is reflected from the surface of the gem or precious stone is not received by the particular light receiver,

wherein the one or more first light receivers have at least a first critical height and the one or more second light receivers have at least a second critical height different from the first critical height,

wherein the probe is covered by a removable tip that has a thickness less than the first and second critical heights.

33. The method of claim 1, wherein the probe is moved over an area of the gem or precious stone, wherein the step of measuring the optical characteristics is based on multiple measurements taken over the area.

34. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes coupling light to a light sensing element, wherein prior to coupling of the light to the light sensing element a radial or angular distribution pattern of the light is reduced or removed.

35. The method of claim 1, wherein the gem or precious stone comprises a diamond, pearl, ruby, sapphire, emerald, opal, amethyst or coral.

36. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes at least a first measurement of a first gem or precious stone taken at a first point in time and a second measurement taken at a second point in time;

wherein based on the first and second measurements a determination is made of whether the second measurement is a measurement of the first gem or precious stone or another object.

37. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes a valuation assessment of the gem or precious stone.

38. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone results in an insurance assessment of the gem or precious stone.

39. The method of claim 1, wherein the step of measuring the optical characteristics of the gem or precious stone includes an assessment of whether the gem or precious stone has undergone a change.