Apparatus and method for measuring optical characteristics of an object

• US 6,417,917 B1
• Filed: 01/08/2001
• Issued: 07/09/2002
• Est. Priority Date: 01/02/1996
• Status: Expired due to Term

• Current Assignee: RPX Corporation
• Original Assignee: LJ Laboratories L.L.C.
• Inventors: Jung, Wayne D., Jung, Russell W., Loudermilk, Alan R.
• Primary Examiner(s): Pham, Hoa Q.
• Application Number:
  US09/657,770
• Time in Patent Office: 547 Days
• Field of Search: 356/73, 356/371, 356/372, 356/373, 356/445, 356/446, 356/416, 356/417, 356/419, 356/402, 356/405, 356/406, 356/407, 356/317, 356/318, 356/326, 356/328, 250/227.11, 250/227.21, 250/227.23, 250/227.28, 250/231.1, 250/227.24, 433/29, 433/26, 433/203.1
• US Class Current: 356/73
• CPC Class Codes: A61B 2560/0233 Optical standards
• CPC Class Codes: A61B 2562/247 Hygienic covers, i.e. for covering the sensor or apparatus during use
• CPC Class Codes: A61B 5/0088 for oral or dental tissue
• CPC Class Codes: A61C 19/10 Supports for artificial teeth for transport or for comparison of the colour
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/0272 Handheld
• CPC Class Codes: G01J 3/04 Slit arrangements slit adjustment
• CPC Class Codes: G01J 3/10 Arrangements of light sources specially adapted for spectrometry or colorimetry
• CPC Class Codes: G01J 3/46 Measurement of colour; Colour measuring devices, e.g. colorimeters measuring colour temperature G01J5/60
• CPC Class Codes: G01J 3/50 using electric radiation detectors
• 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
• CPC Class Codes: G07D 7/1205 Testing spectral properties
• CPC Class Codes: G07D 7/17 Apparatus characterised by positioning means or by means responsive to positioning

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. Such methods and implements may be desirably utilized for purposes of detecting and preventing counterfeiting or the like.

Claims

1. A method comprising the steps of:

providing light to a surface of an object with a probe and receiving light from the object, wherein light is provided from the probe by a light source and light is received by one or more light receivers, wherein the light source and one or more of the light receivers define a critical height from the surface below which no light from the light source that is specularly reflected from the object is received by the one or more of the light receivers;

determining an intensity of light received by the one or more light receivers by coupling the received light to a plurality of sensors through a plurality of filter elements; and

measuring the optical characteristics of the object including at least spectral characteristics of the object, wherein the measurement produces data indicative of the optical characteristics of the object, wherein at least first and second measurements are taken, including at least one measurement taken with the probe below the critical height for one or more of the light receivers.

2. The method of claim 1, wherein the optical characteristics further comprise translucence, gloss, opalescence or surface texture characteristics.

3. The method of claim 1, wherein the sensors comprise first and second optical sensors, wherein the second optical sensors measure received light of the same bandwidth, and wherein the first optical sensors and filter elements comprise a spectrophotometer or a color tristimulus measuring device.

4. The method of claim 1, wherein the probe is moveable, wherein the probe is positioned in proximity to the object by relative movement of the probe in proximity to the object.

5. The method of claim 1, wherein the optical characteristics of the object are determined without the probe contacting the object.

6. The method of claim 1, wherein optical characteristics of the object are determined when the probe is at a predetermined distance and/or angle with respect to the object.

7. The method of claim 1, wherein a material mixing unit receives data indicative of the optical characteristics, wherein the material mixing unit prepares constituent materials for a second object based on the data indicative of the optical characteristics, wherein the constituent materials of the second object are selected based on the data indicative of the optical characteristics.

8. The method of claim 1, wherein the object is selected from the group consisting of skin, paint, fabric, a photograph, a dental object, a printed object, hair, and makeup.

9. The method of claim 1, wherein the optical characteristics are determined by the generation of first data indicative of color characteristics and second data indicative of translucence characteristics, wherein the first data are adjusted based on the second data.

10. The method of claim 1, further comprising the step of selectively providing light bias to one or more of the sensors.

11. A method comprising the steps of:

providing light to a surface of an object with a probe and receiving light from the object, wherein light is provided from the probe by a light source and light is received by one or more light receivers, wherein the light source and one or more of the light receivers define a critical height from the surface below which no light from the light source that is specularly reflected from the object is received by the one or more of the light receivers;

determining an intensity of light received by the one or more light receivers by coupling the received light to a plurality of light to frequency converter sensing elements through a plurality of filter elements; and

measuring the optical characteristics of the object including at least spectral characteristics of the object, wherein the measurement produces data indicative of the optical characteristics of the object, wherein at least first and second measurements are taken, including at least one measurement taken with the probe below the critical height for one or more of the light receivers.

12. The method of claim 11, wherein the optical characteristics further comprise translucence, gloss, opalescence or surface texture characteristics.

13. The method of claim 11, wherein the light to frequency converter sensing elements comprise first and second optical sensors, wherein the second optical sensors measure received light of the same bandwidth, and wherein the first optical sensors and filters comprise a spectrophotometer or a color tristimulus measuring device.

14. The method of claim 11, wherein the probe is moveable, wherein the probe is positioned in proximity to the object by relative movement of the probe in proximity to the object.

15. The method of claim 11, wherein the optical characteristics of the object are determined without the probe contacting the object.

16. The method of claim 11, wherein optical characteristics of the object are determined when the probe is at a predetermined distance and/or angle with respect to the object.

17. The method of claim 11, wherein a material mixing unit receives data indicative of the optical characteristics, wherein the material mixing unit prepares constituent materials for a second object based on the data indicative of the optical characteristics, wherein the constituent materials of the second object are selected based on the data indicative of the optical characteristics.

18. The method of claim 11, wherein the object is selected from the group consisting of skin, paint, fabric, a photograph, a dental object, a printed object, hair, and makeup.

19. The method of claim 11, wherein the optical characteristics are determined by the generation of first data indicative of color characteristics and second data indicative of translucence characteristics, wherein the first data are adjusted based on the second data.

20. The method of claim 11, further comprising the step of selectively providing light bias to one or more of the light to frequency converter sensing elements.

21. The method of claim 11, wherein the light is coupled to one or more of the light to frequency converter sensing elements by one or more aspheric lenses.

22. A method comprising the steps of:

providing light to a surface of an object with a probe and receiving light from the object, wherein light is provided from the probe by a light source and light is received by one or more light receivers, wherein the light source and one or more of the light receivers define a critical height from the surface below which no light from the light source that is specularly reflected from the object is received by the one or more of the light receivers;

determining an intensity of light received by the one or more light receivers by coupling the received light to a plurality of sensors through a plurality of filter elements; and

measuring the optical characteristics of the object including at least spectral characteristics of the object, wherein the measurement produces data indicative of the optical characteristics of the object, wherein at least one measurement is taken, wherein the at least one measurement comprises a measurement taken with the probe below the critical height for one or more of the light receivers.

23. The method of claim 22, wherein the optical characteristics further comprise translucence, gloss, opalescence or surface texture characteristics.

24. The method of claim 22, wherein the sensors comprise first and second optical sensors, wherein the second optical sensors measure received light of the same bandwidth, and wherein the first optical sensors and filters comprise a spectrophotometer or a color tristimulus measuring device.

25. The method of claim 22, wherein the probe is moveable, wherein the probe is positioned in proximity to the object by relative movement of the probe in proximity to the object.

26. The method of claim 22, wherein the optical characteristics of the object are determined without the probe contacting the object.

27. The method of claim 22, wherein optical characteristics of the object are determined when the probe is at a predetermined distance and/or angle with respect to the object.

28. The method of claim 22, wherein a material mixing unit receives data indicative of the optical characteristics, wherein the material mixing unit prepares constituent materials for a second object based on the data indicative of the optical characteristics, wherein the constituent materials of the second object are selected based on the data indicative of the optical characteristics.

29. The method of claim 22, wherein the object is selected from the group consisting of skin, paint, fabric, a photograph, a dental object, a printed object, hair, and makeup.

30. The method of claim 22, wherein the optical characteristics are determined by the generation of first data indicative of color characteristics and second data indicative of translucence characteristics, wherein the first data are adjusted based on the second data.

31. The method of claim 22, further comprising the step of selectively providing light bias to one or more of the sensors.

32. A method comprising the steps of:

providing light to a surface of an object with a probe and receiving light from the object, wherein light is provided from the probe by a light source and light is received by one or more light receivers, wherein the light source and one or more of the light receivers define a critical height from the surface below which no light from the light source that is specularly reflected from the object is received by the one or more of the light receivers;

determining an intensity of light received by the one or more light receivers by coupling the received light to a plurality of light to frequency converter sensing elements through a plurality of filter elements; and

measuring the optical characteristics of the object including at least spectral characteristics of the object, wherein the measurement produces data indicative of the optical characteristics of the object, wherein at least one measurement is taken, wherein the at least one measurement comprises a measurement taken with the probe below the critical height for one or more of the light receivers.

33. The method of claim 32, wherein the optical characteristics further comprise translucence, gloss, opalescence or surface texture characteristics.

34. The method of claim 32, wherein the light to frequency converter sensing elements comprise first and second optical sensors, wherein the second optical sensors measure received light of the same bandwidth, and wherein the first optical sensors and filters comprise a spectrophotometer or a color tristimulus measuring device.

35. The method of claim 32, wherein the probe is moveable, wherein the probe is positioned in proximity to the object by relative movement of the probe in proximity to the object.

36. The method of claim 32, wherein the optical characteristics of the object are determined without the probe contacting the object.

37. The method of claim 32, wherein optical characteristics of the object are determined when the probe is at a predetermined distance and/or angle with respect to the object.

38. The method of claim 32, wherein a material mixing unit receives data indicative of the optical characteristics, wherein the material mixing unit prepares constituent materials for a second object based on the data indicative of the optical characteristics, wherein the constituent materials of the second object are selected based on the data indicative of the optical characteristics.

39. The method of claim 32, wherein the object is selected from the group consisting of skin, paint, fabric, a photograph, a dental object, a printed object, hair, and makeup.

40. The method of claim 32, wherein the optical characteristics are determined by the generation of first data indicative of color characteristics and second data indicative of translucence characteristics, wherein the first data are adjusted based on the second data.

41. The method of claim 32, further comprising the step of selectively providing light bias to one or more of the light to frequency converter sensing elements.

42. The method of claim 32, wherein the light is coupled to one or more of the light to frequency converter sensing elements by one or more aspheric lenses.