Apparatus and method for measuring optical characteristics of an object

• US 6,538,726 B2
• Filed: 06/03/2002
• Issued: 03/25/2003
• Est. Priority Date: 07/10/1998
• Status: Expired due to Fees

• Current Assignee: RPX Corporation
• Original Assignee: LJ Laboratories L.L.C.
• Inventors: Loudermilk, Alan R., DeJung, Wayne, Jung, Russell W.
• Primary Examiner(s): Pham, Hoa Q.
• Application Number:
  US10/161,853
• Publication Number:
  US 20020180953A1
• Time in Patent Office: 295 Days
• Field of Search: 356/73, 356/371, 356/600, 356/614, 356/601, 356/445-448, 356/416, 356/417, 356/419, 356/402, 356/405, 356/406, 356/407, 356/317, 356/318, 356/326, 356/328, 250/277.11, 250/227.21, 250/227.23, 250/237.28, 250/227.24, 250/231.1
• US Class Current: 356/73
• CPC Class Codes: G01J 3/513 having fixed filter-detector pairs
• CPC Class Codes: G01N 2021/4742 comprising optical fibres
• CPC Class Codes: G01N 2021/4747 Concentric bundles
• 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

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 or material and receiving light from the object or material, wherein light is provided by at least one light source and light is received by one or more fiber optic light receivers, wherein the one or more fiber optic light receivers receive light that has a radial and/or angular light distribution pattern;

removing at least part of the radial and/or angular light distribution pattern from the light received by the one or more fiber optic light receivers to produce radial/angular-distribution-pattern-reduced light;

coupling the radial/angular-distribution-pattern-reduced light to a spectral measurement device;

determining one or more optical characteristics of the object or material including at least spectral characteristics of the object or material, wherein at least one spectral measurement is taken with the spectral measurement device, wherein data indicative of the optical characteristics of the object or material is generated based on the at least one spectral measurement.

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 spectral measurement device measures spectral characteristics of light by coupling light to a plurality of sensors through a plurality of filter elements.

4. The method of claim 3, wherein the plurality of sensors comprise light to frequency converter sensing elements.

5. The method of claim 4, further comprising the step of selectively providing light bias to one or more of the light to frequency converter sensing elements.

6. The method of claim 4, wherein the spectral measurement device comprises a spectrophotometer or a color tristimulus measuring device.

7. The method of claim 4, wherein light is coupled to one or more of the light to frequency converter sensing elements by one or more aspheric lenses.

8. The method of claim 3, wherein light is coupled to the plurality of sensors via one or more aspheric lenses.

9. The method of claim 1, wherein the at least one light source and the one or more fiber optic light receivers are part of a probe, wherein the probe is moveable, wherein the probe is positioned in proximity to the object or material by relative movement of the probe in proximity to the object or material.

10. The method of claim 9, wherein the optical characteristics of the object or material are determined without the probe contacting the object or material.

11. The method of claim 9, wherein optical characteristics of the object or material are determined when the probe is at a predetermined distance and/or angle with respect to the object or material.

12. 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 or material based on the data indicative of the optical characteristics, wherein the constituent materials of the second object or material are selected based on the data indicative of the optical characteristics.

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

14. 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.

15. The method of claim 1, further comprising the step of selectively providing light bias to one or more light sensing elements.

16. The method of claim 1, wherein the at least one light source, the one or more fiber optic light receivers, and the spectral measurement device are included within a handheld unit, wherein light is presented to the object or material by directing the handheld unit towards the object or material, wherein one or more optical characteristics of the object or material including at least spectral characteristics of the object or material are determined based on light received by one or more fiber optic light receivers, wherein radial and/or angular light distribution patterns are removed from the light received by the one or more fiber optic light receivers prior to the light being coupled to the spectral measurement device.

17. The method of claim 16, wherein the object or material is selected from the group consisting of skin, paint, fabric, a photograph, a dental object, a printed object, hair, and makeup.

18. The method of claim 17, wherein the optical characteristics further comprise translucence, gloss, opalescence or surface texture characteristics.