Apparatus and method for measuring optical characteristics of an object

• US 7,397,541 B2
• Filed: 09/18/2006
• Issued: 07/08/2008
• Est. Priority Date: 01/02/1997
• Status: Expired due to Fees

• Current Assignee: RPX Corporation
• Original Assignee: SSL Technologies LLC
• Inventors: Jung, Wayne D., Jung, Russell W., Loudermilk, Alan R.
• Primary Examiner(s): EVANS, FANNIE L
• Application Number:
  US11/523,798
• Publication Number:
  US 20070115472A1
• Time in Patent Office: 659 Days
• Field of Search: 356/402, 356/419, 356/73
• US Class Current: 356/73
• CPC Class Codes: A61C 13/0003 Making bridge-work, inlays, implants or the like
• CPC Class Codes: A61C 13/0004 Computer-assisted sizing or machining of dental prostheses
• CPC Class Codes: G01J 2003/1234 Continuously variable IF [CVIF]; Wedge type
• CPC Class Codes: G01J 2003/1239 and separate detectors
• CPC Class Codes: G01J 3/02 Details
• CPC Class Codes: G01J 3/0218 using optical fibers
• CPC Class Codes: G01J 3/0278 Control or determination of height or angle information for sensors or receivers
• CPC Class Codes: G01J 3/0291 Housings; Spectrometer accessories; Spatial arrangement of elements, e.g. folded path arrangements
• 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: G01N 2021/6463 Optics
• CPC Class Codes: G01N 2021/6484 Optical fibres
• CPC Class Codes: G01N 21/251 Colorimeters; Construction thereof
• CPC Class Codes: G01N 21/255 Details, e.g. use of specially adapted sources, lighting or optical systems
• CPC Class Codes: G01N 21/474 Details of optical heads therefor, e.g. using optical fibres
• CPC Class Codes: G01N 21/645 Specially adapted constructive features of fluorimeters
• CPC Class Codes: G01N 21/6486 Measuring fluorescence of biological material, e.g. DNA, RNA, cells G01N21/6428 takes precedence
• CPC Class Codes: G02B 6/3825 with an intermediate part, e.g. adapter, receptacle, linking two plugs
• CPC Class Codes: G02B 6/4292 : the light guide being disconnectable from the opto-electronic element, e.g. mutually self aligning arrangements
• CPC Class Codes: G16H 20/40 : relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture

Abstract

Color/optical characteristics measuring systems and methods are disclosed. Perimeter receiver fiber optics/elements are spaced apart from a central source fiber optic/element and received light reflected from the surface of the object is 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 being measured. Under processor control, the color measurement may be made at a predetermined height and angle. Various color spectral photometer arrangements are disclosed. Translucency, fluorescence 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.

Claims

1. A method for determining optical characteristics of an object, comprising the steps of:

providing light to the object from one or more light sources, and receiving light from the object through one or more light receivers, wherein the one or more light sources and one or more light receivers define at least one minimal height, wherein below the minimal height light that is reflected from a surface of the object is not propagated by the one or more light receivers, wherein the light is provided to the object and received from the object through a protective barrier having a thickness, wherein the thickness is less than the minimal height;

measuring the intensity of light received and propagated by one of the one or more light receivers;

determining the optical characteristics of the object based in response to one or more intensity measurements.

2. The method of claim 1, wherein at least two measurements are taken, wherein the optical characteristics include color characteristics and translucence characteristics.

3. The method of claim 1, wherein at least one measurement is taken below the minimal height.

4. The method of claim 1, wherein light received and propagated by the one of the one or more light receivers is coupled to one or more light-to-frequency converter elements, wherein the intensity of light in a plurality of spectral bands or of a plurality of wavelengths is measured by coupling signals from the one or more light-to-frequency converter elements to a processing element.

5. The method of claim 4, wherein the intensity of light in the plurality of spectral bands or of a plurality of wavelengths is measured by reading a plurality of output signals from the one or more light-to-frequency converter elements at periodic time intervals via a timing loop.

6. The method of claim 5, wherein the timing loop is implemented via software.

7. The method of claim 4, wherein the light is coupled to a plurality of light-to-frequency converter elements via a plurality of filter elements.

8. The method of claim 7, wherein the filter elements comprise bandpass filters.

9. The method of claim 1, wherein the protective barrier comprises a disposable shield.

10. The method of claim 1, wherein a calibration measurement is taken through the protective barrier, wherein the optical characteristics are determined based on data generated by the calibration measurement.

11. The method of claim 1, wherein one or more sensors are coupled to the one or more light receivers, wherein the one or more sensors produce data indicative of a physical position with respect to the object.

12. The method of claim 11, wherein, based on the data indicative of the physical position with respect to the object data from the one or more intensity measurements are selectively accepted, rejected or compensated.

13. The method of claim 1, wherein data indicative of the optical characteristics of the object are output in the form of a closest match or matches to one or more shade values.

14. The method of claim 1, wherein data indicative of the optical characteristics of the object are output in the form of a recipe of materials.

15. The method of claim 14, wherein the recipe of materials is used to produce a second object having optical characteristics corresponding to optical characteristics of the object.

16. The method of claim 14, wherein the recipe of materials comprises one or more materials containing one or more pigments.

17. The method of claim 1, wherein data indicative of the optical characteristics of the object are selectively output in the form of a closest match or matches to one or more shade values or in the form of a recipe of materials.

18. The method of claim 17, wherein the recipe of materials is used to produce a second object having optical characteristics corresponding to optical characteristics of the object.

19. The method of claim 1, wherein audio feedback is provided to an operator, wherein the audio feedback conveys information indicative of the status of the optical characteristics determination process.

20. The method of claim 1, wherein the object comprises a dental object, wherein at least two measurements are taken and data indicative of color characteristics and translucence characteristics are generated, wherein data indicative of the optical characteristics of the object are selectively output in the form of a closest match or matches to one or more shade values or in the form of a recipe of materials, wherein the recipe of materials is used to produce a second object having optical characteristics corresponding to optical characteristics of the object.