MXPA98005172A - Apparatus and method for measuring the optical characteristics of the die - Google Patents
Apparatus and method for measuring the optical characteristics of the dieInfo
- Publication number
- MXPA98005172A MXPA98005172A MXPA/A/1998/005172A MX9805172A MXPA98005172A MX PA98005172 A MXPA98005172 A MX PA98005172A MX 9805172 A MX9805172 A MX 9805172A MX PA98005172 A MXPA98005172 A MX PA98005172A
- Authority
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- Mexico
- Prior art keywords
- tooth
- light
- probe
- results
- detectors
- Prior art date
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Abstract
Systems and methods of color measurement are exposed such as to determine the color or other characteristics of the teeth. The optical receiver fibers perimeter are separated from a fiber optic of the central source and receive light reflected from the surface of the object / tooth to be measured. The light of the perimetric optical fibers passes to a variety of filters. The system uses the optical receiver fibers perimeter to determine the information regarding the height and angle of the probe with respect to the object / tooth to be measured. Under a processor control, the color measurement could be done at a certain height and angle. Various arrangements of color spectrum photometer are exposed. The results of transfer, fluorescence and / or surface texture could also be obtained. Audio feedback could be provided to guide the operator using the system. The probe may have a removable or shielded tip to prevent contamination. A production method for dental prostheses based on measured results is also exposed. The measured results could also be stored and / or organized as part of a patient database
Description
Apparatus and Method for Measuring the Optical Characteristics of the Tooth
Field of the Invention
The present invention relates to devices and methods for measuring optical characteristics such as color of objects such as the tooth, and more particularly to devices and methods for measuring color and other optical characteristics of the tooth, or other objects or surfaces with a manual probe that presents minimal problems with height or other angular dependencies.
Background of the Invention
A need is recognized for devices and methods of measuring the color or other optical characteristics of the tooth and other objects in the field of dentistry. Various devices that measure color such as spectrophotometers and colorimeters are known in the art. To understand the limitations of such conventional devices, it is useful to understand certain principles that relate to color. Unintended by the theory, the Requesters provide the following discussion. In the discussion here, reference is made to an "object," etc., and it should be understood that in
REF: 27678 general such discussion could include the tooth as the "object."
The color of an object determines the manner in which light is reflected from the surface of an object. When light is incident on an object, the reflected light will vary in intensity and wavelength depending on the color of the surface of the object. Thus, a red object will reflect red light with greater intensity than a blue object or a green object, and correspondingly a green object will reflect green light with a greater intensity than a red object or a blue object.
One method of quantifying the color of an object is to illuminate it with broadband spectrum or "white" light, and measure the spectral properties of the reflected light during the total visible spectrum and compare the reflected spectrum with the incident light spectrum. Such instruments typically require a broadband spectrophotometer, which are generally expensive, bulky and relatively difficult to operate, hence limiting the practical application of such instruments.
For certain applications, the broadband results provided by a spectrophotometer are unnecessary. For such applications, devices have been produced or proposed that quantify the color in terms of a numerical value or a relatively small group of values representative of the color of the object.
It is known that the color of an object can be represented by three values. For example, the color of an object can be represented by red, green and blue values, an intensity value and color difference values, by a CIÉ value, or by what is known as "triple stimulus values" or numerous other values. orthogonal combinations. It is important that the three values be orthogonal; p. ex. , any combination of two elements in the group can not be included in the third element.
One such method of quantifying the color of an object is to illuminate an object with broadband "white" light and measure the intensity of the reflected light after it has passed through narrow band filters. Three filters (such as red, green and blue) are typically used to provide triple light stimulus values representative of the color of the surface. Yet another method is to illuminate an object with three monochromatic light sources
(such as, red, green and blue) one at a time and then measure the intensity of the reflected light with a simple light detector. The three measurements are then converted to a triple stimulus value representative of the surface color. Such color measurement techniques can be used to produce equivalent triple-stimulus values representative of the color of the surface. In general, it is not a problem if a "white" light source with a plurality of color detectors (or a continuum in the case of the spectrophotometer) is used, or if a plurality of color light sources are used with a color detector. simple light.
There are, however, difficulties with conventional techniques. When light is incident on a surface and reflected to a light receiver, the light and angle of the light detector relative to the surface and to the light source also affects the intensity of the received light. Since the determination of color is made to determine by measurement and quantification of the intensity of light received for different colors, it is important that the angular dependence of the light receiver be eliminated or explained in some way.
One method to eliminate the angular dependence of the light source and receiver is to provide a fixed mounting arrangement where the light source and receiver are stationary and the object is always positioned and measured at an angle of adjustment. The fixed mounting arrangement greatly limits the applicability of such a method. Another method is to add mounting slots to the light source and receiver of the probe and touch the object with the probe to maintain and constant angle. The support grooves in such an apparatus should be wide enough to ensure that a constant angle (usually perpendicular) is maintained relative to the object. Such an apparatus tends to be very difficult to use in small objects or in objects that are difficult to reach, and in general it does not work satisfactorily in measuring objects with curved surfaces. Such devices are particularly difficult to implement in the field of dentistry.
The use of color measuring devices in the field of dentistry has been proposed. In modern dentistry, tooth color is typically quantified by manually comparing a patient's tooth with a group of "shadow guides." There are numerous shade guides available for dentists to properly select the desired color of dentures. Such shade guides have been used for decades and the determination of color is subjectively carried out by the dentist, keeping a group of shadow guides close to the patient's tooth and trying to find the best pair. Unfortunately, however, often the best partner is affected by the color of the ambient light in the dental operation and the color that surrounds the patient's makeup or clothing and by the level of fatigue of the dentist. In addition, such pseudo-tests and error methods based on subjective comparison with existing industrial shade guides to form dental prostheses, fillings and the like often result in unacceptable color comparison, with the result that the prosthesis needs to be reworked, leading to increase costs and inconvenience to the patient, dental professional and / or prosthesis manufacturer.
The subjective color quantification is also carried out in the paint industry by comparing the color of an object with a reference guide of paint. There are numerous paint guides available in the industry and frequently the color determination is affected by the color of the ambient light, the user's fatigue and the color sensitivity of the user. Many individuals are insensitive (color blindness) to certain colors, further complicating the determination of color.
While a need has been recognized in the field of dentistry, however, the limitations of conventional color / optical measurement techniques typically restrict the utility of such techniques. For example, the high cost and bulkiness of typical broadband spectrophotometers, and the fixed mounting arrangements or support grooves required to address it and the angular dependence, often limit the applicability of such conventional techniques.
In addition, another limitation of such conventional methods and devices is that the resolution of angular dependency problems typically requires contacting the object to be measured. In certain applications, it may be desirable to measure and quantify the color of an object with a small probe that does not require contact with the surface of the object. In certain applications, for example, hygienic considerations make such contact undesirable. In other applications, contact with the object may damage the surface (such as if the object is coated in some way) or otherwise cause undesirable effects.
In summary, there is a need for a low cost, small quantity manual probe that can efficiently measure the color and other optical characteristics of an object without requiring physical contact with the object, and also a need for methods based on such a device in the field of dentistry and other applications.
Brief Description of the Invention
In accordance with the present invention, devices and methods are provided for efficiently measuring the color and other optical characteristics of objects such as the tooth, and with minimal problems of angular dependence. A hand probe is used in the present invention, with the hand probe containing a number of optical fibers in certain preferred embodiments. The light is directed from one (or more) light sources to the object / tooth to be measured, which in certain preferred embodiments is a fiber optic light source (other sources of light and light source arrangements could be used). The light reflected to the object is detected by a number of light receptors. Included in the light receptors (which could be light receiving optical fibers) are a plurality of perimetric receivers (which could be optical fibers receiving light, etc.). In certain preferred embodiments, three perimeter optical fibers are used to take measurements to a desired, predetermined and angle, thus minimizing the problems of angular dependence encountered in conventional methods. In certain embodiments, the present invention could also measure the transparency and fluorescence characteristics of the object / tooth to be measured, also the surface texture and / or other optical or surface characteristics.
The present invention could include constituent elements of a broadband spectrophotometer, or, alternatively, could include constituent elements of a triple stimulus type colorimeter. The present invention could employ a variety of color measuring devices to measure color in a practical, reliable and efficient manner, and in certain preferred embodiments include a color filter array and a plurality of color detectors. A microprocessor is included for control and calculation purposes. A temperature sensor is included to measure the temperature to detect abnormal conditions and / or to compensate for temperature effects of the filters or other system components. In addition, the present invention could include audio feedback to guide the operator in the elaboration of color / optical measurements, in addition to one or more representation devices for control of representation, status or other information.
With the present invention, measurements of tooth color / optics or the like could be made with a hand probe in a practical and reliable manner, essentially free from problems of angular dependence, without using accessories, support grooves or other undesirable mechanical arrangements for fix the and the angle of the probe with respect to the object / tooth. In addition, the present invention includes methods that use such color measurement results to implement the process for forming dental prostheses and the like, in addition to methods for maintaining such color and / or other results as part of the patient's record database.
Therefore, it is an object of the present invention to address the limitations of conventional color / optical measurement techniques.
It is another object of the present invention to provide a method and device useful in the measurement of the color or other optical characteristics of the tooth or other objects or surfaces with a hand-held practical sizing probe that does not require contact with the object or surface.
It is a further object of the present invention to provide a probe and color / optical measurement method that does not require mechanical mounting of fixed position, support grooves or other mechanical impediments.
It is still another object of the present invention to provide a probe and method useful for the measurement of color or other optical characteristics that could be used than a probe located simply near the surface to be measured.
It is yet a further object of the present invention to provide a probe and method that are capable of determining the transparency characteristics of the object to be measured.
It is a further object of the present invention to provide a probe and method that is capable of determining the surface texture characteristics of the object / tooth to be measured.
It is still a further object of the present invention to provide a probe and method that are capable of determining the fluorescence characteristics of the object / tooth to be measured.
It is another object of the present invention to provide a probe and method that can measure the area of a small singular spot, or that can also measure the color of irregular shapes by moving the probe over an area and integrating the color of the total area.
It is a further object of the present invention to provide a method of measuring tooth color and preparing dentures, dentures, intraoral tooth-colored fillings or other materials.
It is still another object of the present invention to provide a method and apparatus that minimizes contamination problems, while providing a reliable and convenient way in which to measure the tooth and prepare dental prostheses, dentures, intraoral tooth-colored fillings or other materials.
It is an object of the present invention to provide methods that use measurement results to implement the process forming dentures and the like, in addition to methods for maintaining such measurements and / or other results as part of the patient's record database.
It is also an object of the present invention to provide probes and methods for measuring the optical characteristics with a probe that remains substantially stationary with respect to the object or tooth to be measured.
Finally, it is an object of the present invention to provide probes and methods for measuring optical characteristics with a probe that could have a removable or protective tip that could be removed for cleaning, after use or the like.
Brief Description of the Drawings
The present invention could be more fully understood by a description of certain preferred embodiments in conjunction with the appended drawings in which:
FIG. 1 is a diagram illustrating a preferred embodiment of the present invention;
FIG. 2 is a diagram illustrating a cross section of a probe according to a preferred embodiment of the present invention;
FIG. 3 is a diagram illustrating an arrangement of fiber optic receivers and detectors used with a preferred embodiment of the present invention;
FIGS. 4A to 4C illustrate certain geometrical considerations of the optical fibers;
FIGS. 5A and 5B illustrate the amplitude of light received by fiber optic light receivers as a function of the weight of an object;
FIG. 6 is a flow diagram illustrating a method of measuring color according to an embodiment of the present invention;
FIGS. 7A and 7B illustrate a protective cap that could be used with certain embodiments of the present invention;
FIGS. 8A and 8B illustrate removable probe tips that could be used with certain embodiments of the present invention;
FIG. 9 illustrates a fiber optic package according to another preferred embodiment of the present invention;
FIGS. 10A, 10B, 10C and 10D illustrate and describe other fiber optic package configurations that could be used according to still other preferred embodiments of the present invention;
FIG. 11 illustrates a linear optical detector array that could be used in certain embodiments of the present invention;
FIG. 12 illustrates an array array detector arrangement that could be used in certain embodiments of the present invention;
FIGS. 13A and 13B illustrate certain optical properties of a filter array that could be used in certain embodiments of the present invention;
FIGS. 14A and 14B illustrate examples of light intensities received from receivers used in certain embodiments of the present invention;
FIG. 15 is a flow chart illustrating audio tones that could be used in certain preferred embodiments of the present invention;
FIG. 16 is a flow chart illustrating a method of manufacturing a dental prosthesis according to a preferred embodiment of the present invention;
FIGS. 17A and 17B illustrate a positioning tool used in certain embodiments of the present invention;
FIG. 19 illustrated an integrated unit according to the present invention that includes a measuring device and other tools;
FIG. 20 illustrates one embodiment of the present invention, which utilizes a plurality of rings of light receptors that could be used to take measurements with the probe held substantially stationary with respect to the object to be measured;
FIGS. 21 and 22 illustrate one embodiment of the present invention, which utilizes a mechanical movement and which could also be used to take measurements with the probe held substantially stationary with respect to the object to be measured;
FIGS. 23A to 23C illustrate embodiments of the present invention in which connected light conduits could serve as removable probe tips;
FIGS 24, 25 and 26 illustrate further embodiments of the present invention using intraoral reflectometers, intraoral cameras and / or color calibration charts in accordance with the present invention; Y
FIG. 27 illustrates an embodiment of the present invention in which interoral chamber and / or other instruments in accordance with the present invention could be adapted for use with a dental chair.
Detailed Description of the Preferred Modalities
The present invention will be described in greater detail with reference to certain preferred embodiments. In several places here, reference is made for example to an "object". It should be understood that an exemplary use of the present invention is the field of dentistry, and thus it should be understood that the object typically includes teeth, dentures, dental-type cements, although for the purpose of discussion in certain examples only reference is made to the "object " As described elsewhere here, various refinements and substitutions of various modalities are possible based on the principles of the teachings here.
With reference to FIG. 1, an exemplary preferred embodiment of a characteristic color / optical measurement system and method according to the present invention will be described. It should be noted that, in various places here, such a color measurement system is sometimes referred to as an intraoral reflex, etc.
The tip of the probe 1 includes a plurality of optical fibers, each of which could constitute one or more fiber optic fibers. In a preferred embodiment, the optical fibers contained within the tip of the probe 1 include a single fiber optic light source and three fiber optic light receptors. The use of such optical fibers for measuring the color or other optical characteristics of an object will be described hereinafter. The tip of the probe 1 is connected to the body of the probe 21, on which the switch 17 is fixed. The switch 17 communicates with the microprocessor 10 through the wire 18 and provides, for example, a mechanism by means of which an operator could activate the device to perform a color / optical measurement. The optical fibers within the tip of the probe 1 terminate at the front end thereof (eg, the far end of the body of the probe 2). The forward end of the tip of the probe 1 is directed towards the surface of the object to be measured as described in more detail below. The optical fibers within the tip of the probe 1 optically extend through the fiber optic cable 3 to the light detectors 8, which are coupled to the microprocessor 10.It should be noted that the microprocessor 10 includes associated conventional components, such as memory
(programmable memory, such as PROM, EPROM or EEPROM, working memory such as DRAM or SRAM, and / or other types of memory such as non-volatile memory, such as FLASH), peripheral circuits, clocks and power supplies, although for clarity such components are not explicitly shown. Other types of computing devices (such as other microprocessor systems, programmable logic arrays or the like) are used in other embodiments of the present invention.
In the embodiment of FIG. 1, the optical fibers of the fiber optic cable 3 terminate at the junction connector 4. From the junction connector 4, each of the three fiber optic receivers used in this embodiment join at least five smaller optical fibers (generally it is denoted as fibers 7), which in this embodiment are fibers of the same diameter, but which in other embodiments could be of different diameter (such as a smaller or larger height / angle or perimetric fiber, as fully described herein). One of the fibers of each group of five fibers passes to the light detectors 8 through a neutral density filter (as described more fully with reference to FIG 3), and collectively such neutrally filtered fibers are used for purpose of height / angle determination, (and could also be used to measure surface characteristics, as described more fully here). Four of the fibers that remain in each fiber group pass the light detectors 8 through the color filters and are used to make the color / optical measurement. In still other embodiments, the union connector 4 is not used, and fiber bundles of, for example, five or more fibers each extend from the light detectors 8 to the forward end of the probe tip 1. In certain embodiments, unused fibers or other materials could be included as part of a bundle of fibers for the purpose of, for example, ease of the manufacturing process for the fiber bundle. What should be noted is that, for the purpose of the present invention, a plurality of light-receiving optical fibers or elements (such as fibers 7) are presented to the light detectors 8, with the light of the optical fiber elements receiving the light. light representing light reflected from an object 20. While the different modalities described here present changes and benefits that could not have been apparent before the invention (and thus could be independently new), what is important for the present discussion is that the light of the fiber optic elements at the front end of the tip of the probe 1 is presented to the detectors 8 for color / optical measurements in the determination of angle / height, etc.
The light source 11 in the preferred embodiment is a halogen light source (of, for example, 5-100 watts, with the chosen voltage of the particular application), which could be under the control of the microprocessor 10. The light of the light source 11 reflects from the cold reflector 6 and within the fiber optic source 5. The fiber optic source 5 passes through the forward end of the tip of the probe 1 and provides the light stimulus used for the purpose of Preparation of the measurements described here. The cold reflector 6 reflects visible light and passes infrared light, and is used to reduce the amount of infrared light produced by the light source 11 before the light is introduced into the fiber optic source 5. Such a reduction in Infrared light from the halogen source such as the light source 11 can help to avoid saturation of the light received by the detectors, which can reduce the overall sensitivity of the system. The fiber 15 receives light directly from the light source 11 and passes to the light detectors 8 (which could be through a neutral density filter). The microprocessor 10 monitors the light output from the light source 11 through the fiber 15, and in this way could monitor and, if necessary compensate, scatter from the output of the light source 11. In certain embodiments, the microprocessor 10 could also sound an alarm (such as by means of speaker 16) or otherwise provide some indication if abnormality or other undesired performance of the light source is detected 11.
The output data of the light detectors 8 is passed to the microprocessor 10. The microprocessor 10 processes the data of the light detectors 8 to produce a color measurement and / or other characteristics. The microprocessor 10 is also coupled to open attenuator switches 12, which serve as an input device. By means of the open attenuator switches 12, the operator could enter control information or commands, or information referring to the object to be measured or the like. In general, open attenuator switches 12, or other appropriate data input devices (such as push button, toggle lever, membrane or other switches or the like), serve as a mechanism for inputting the desired information to the microprocessor 10.
The microprocessor 10 also communicates with UART 13, which allows the microprocessor 10 to be coupled to an external device such as computer 13A. In such modalities, the data provided by the microprocessor 10 could be processed as desired for the particular application, such as for averaging, format conversion or for various options in screen or print presentation, etc. In the preferred embodiment, UART 13 is configured to provide what is known as an RS232 interface, such as is commonly found in personal computers.
The microprocessors 10 also communicate with LCD 14 for display status purpose in display, control or other information as desired for the particular application. For example, color bars, charts or other graphic representations of the color or other data collected and / or the measured object or tooth could be displayed on the screen. In other embodiments, other on-screen display devices, such as CRTs, matrix-type LEDs, lights or other mechanisms are used to produce a visible Index of the state of the system or the like. Due to system initialization, for example, LCD 14 could provide an indication that the system is stable, ready and available to take color measurements.
Also coupled to the microprocessor 10 is the horn 16. The horn 16 in a preferred embodiment as discussed more fully below, serves to provide audio feedback to the operator, which could serve to guide the operator in the use of the device. The horn 16 could also serve to provide status or other information that notifies the operator of the condition of the system, including an audio tone, short duration tones or other audible indication (eg, voice) that the system is initialized and available to take the measurements. The horn 16 could also present audio information indicative of the measured data, shadow guidance or reference values that correspond to the measured data, or an indication of the status of the color / optical measurements.
The microprocessor 10 also receives an input from the temperature sensor 9. Since many types of filters (and perhaps light source or other components) could operate reliably only in a given temperature range, the temperature detector 9 serves to provide information of temperature to the microprocessor 10. In particular, the color filters could be included in the light detectors 8, they could be temperature sensitive, and they could operate reliably only during a certain temperature range. In certain embodiments, if the temperature is within the range of use, the microprocessor 10 could compensate for temperature variations of the color filters. In such embodiments, color filters are characterized according to filtering characteristics as a function of temperature, either by data provided by the filter manufacturer, or by measurement as a function of temperature. Such filter temperature compensation data could be stored in the form of a lookup table in the memory, or they could be stored as a group of polyester coefficients from which the temperature characteristics of the filters could be calculated by the microprocessor 10.
In general, under control of the microprocessor 10, which could be in response to operator activation (by means of, for example, open dimmer switches 12 or switch 17), light is directed from the light source 11, and reflected it is reflected from the cold reflector 6 through the fiber optic source 5 (and through the fiber optic cable 3, the body of the probe 2 and the tip of the probe 1) or by means of some other light source element appropriate) and is directed into the object 20. Light reflected from the object 20 passes through the receiving fiber optic element at the tip of the probe 1 to the light detectors 8 (by means of the body of the probe 2, the fiber optic cable 3 and fibers 7). Based on the information produced by the light detectors 8, the microprocessor 10 produces a color / optical measurement result or other information for the operator. The measurement of color or other data produced by the microprocessor 10 could be displayed on screen on the screen 14, pass from UART 13 to the computer 13A, or used to generate audio information that is presented to the speaker 16. Other operational aspects of the preferred embodiment illustrated in FIG. 1 will be explained later.
With reference to FIG. 2, a preferred embodiment of an optical fiber array presented at the front end of the probe tip 1 will now be described. As illustrated in FIG. 2, a preferred embodiment of the present invention utilizes a single central fiber optic light source, denoted as an optical fiber light source S, and a plurality of perimeter optical light receiving fibers, denoted as light receivers Rl, R2 and R3. As illustrated, a preferred embodiment of the present invention uses three perimetric optical fibers, although in other embodiments two, four or some other number of receiving optical fibers are used. As described more fully herein, the light receiving optical fibers do not serve only to provide reflected light for the purpose of processing the color / optical measurement, but such perimeter fibers also serve to provide information regarding the angle and height of the light. tip of the probe 1 with respect to the surface of the object to be measured, and also provide information regarding the surface characteristics of the object to be measured.
In the preferred embodiment illustrated, the receiver optical fibers Rl to R3 are symmetrically positioned around the optical fiber source S, with a spacing of approximately 120 degrees from each other. It should be noted that the spacing t is provided between the receiver optical fibers Rl to R3 and the fiber optic source S. While the precise angular location of the receiving optical fibers around the perimetry of the fiber bundle is generally not critical, it is have determined that three receiving optical fibers positioned 120 degrees in general could give acceptable results. As discussed above, in certain embodiments the light-receiving optical fibers Rl to R3 constitute each single fiber, which is divided into the joining connector 4 (again with reference to FIG. 1), or, in alternative embodiments, the Light receiving optical fibers R1 to R3 each constitute a bundle of fibers, which number, for example, at least five fibers per pack. It has been determined that, with available fibers of uniform size, a packet of, for example, seven fibers could be efficiently produced (although as will be apparent to one skilled in the art, the precise number of fibers could be determined in view of the desired number of fibers. fibers of receiving optical fibers, manufacturing considerations, etc.). The use of light receiving optical fibers Rl to R3 produce color / optical measurements according to the present invention is further described elsewhere here, although it could be observed that the optical receiving fibers Rl to R3 could serve to detect if, for example, the angle of the tip of the probe 1 with respect to the surface of the object to be measured is 90 degrees, or if the surface of the object to be measured contains surface texture and / or spectral irregularities. In the case where the tip of probe 1 is perpendicular to the surface of the object to be measured is a diffuse deflector (eg, a matte reflector, as compared to a bright type deflector that could have "dots"). "), after the entrance of the light intensity in the perimeter fibers should be approximately equal. It should also be noted that the spacing t serves to adjust the optimal height at which color / optical measurements should be made (as described more fully here).
In a particular aspect of the present invention, the area between the optical fibers on the tip of the probe 1 could be completely or partially filled with a non-reflective and / or surface material (which could be a black matte surface, or another non-reflective surface). reflective). Having such an exposed area of the tip of the probe 1 the non-reflector helps reduce unwanted reflections, thereby helping to increase the efficiency and reliability of the present invention.
With reference to FIG. 3, a partial arrangement of the light receiving optical fibers and detectors used in a preferred embodiment of the present invention will now be described. The fibers 7 represent the optical fibers that receive the light, which transmit the reflected light from the object to be measured to the light detectors 8. In a preferred embodiment, sixteen detectors (two groups of eight) are used, although for ease of discussion only 8 are illustrated in FIG. 3 (in this preferred embodiment, the circuit of FIG.3 is duplicated, for example, to result in ten and six detectors). In other embodiments, other numbers of detectors are used in accordance with the present invention.
The light of the fibers 7 is presented to the detectors 8, which in a preferred embodiment passes through the filters
22 to the detector elements 24. In this preferred embodiment, the detector elements 24 include frequency light converters, manufactured by Texas Instruments and sold under part number TSL230. Such converters, in general, constitute photo diode arrangements that integrate the light received from the fibers 7 and from the AC output signal with a frequency proportional to the intensity (not frequency) of the incident light. Without being destined by theory, the basic principle of such devices is that, as the intensity increases, the output voltage integrator increases more rapidly, and the shorter integrator increases the time, of the higher output frequency. The outputs of the TSL230 detectors are TTL or CMOS compatible digital signals, which could be coupled to several digital logic devices.
The outputs of the detector elements 24 are, in this mode, asynchronous signals of the frequencies that depend on the light intensity presented to the particular detector elements, "which are presented to the processor 26. In a preferred embodiment, the processor 26 is a microprocessor. Microchip PICI6C55 or PICI6C57, which as described more fully here implements an algorithm for measuring the frequencies of the output signals by the detector elements 24. In other embodiments, a more integrated microprocessor / microcontroller, such as Hitachi SH RISC icrocontrollers, is used to provide additional system integration or the like.
As previously described, the processor 26 measures the frequencies of the output signals of the detector elements 24. In a preferred embodiment, the processor 26 implements a time control cycle of the programming element, and at periodic intervals the processor 26 reads the states of the outputs of the detector elements 24. An internal counter is incremented each step through the time control cycle of the programming element. The accuracy of the time control cycle is generally determined by the time base of the crystal oscillator (not shown in FIG.3) coupled to the processor 26 (such oscillators are typically more stable). After reading the outputs of the detector elements 24, the processor 26 performs a unique operation ("XOR") OR with the last data read (in a preferred embodiment such data is read in bit length). If any bit has been changed, the XOR operation will produce 1, and, if the bits have not changed, the XOR operation will produce 0. If the result is not zero, the input bit is saved together with the value of the internal counter (which each step is increased through the time control cycle of the programming element). If the result is zero, the systems expect (eg, execute non-operation instructions) the same amount of time as if the data had to be saved, and the cyclic operation continues. The process continues until all eight entries have been loaded at least twice, allowing the measurement of a full period of each entry. Due to the conclusion of the cyclic process, the processor 26 analyzes the stored input bits and the internal states of the counter. There should be 2 to 16 saved entries (for the total of 8 detectors in FIG 3) and the counter states (if two or more entries change at the same time, they are saved simultaneously). As will be understood by a person skilled in the art, the stored values of the internal counter contain information determining the period of the signals received from the detector elements 24. It could be calculated by appropriately subtracting the internal values of the counter at times when one bit Input has changed. Such calculated periods for each of the outputs of the detector elements is provided by the microprocessor 26 to the microprocessor 10 (see, eg, FIG 1). From such calculated periods, a measurement of the received light intensities could be calculated.
It should be noted that the detector circuit and the methodology illustrated in FIG. 3 have been determined to provide a practical and useful way in which to measure the light intensities received by the detector elements 24. In other embodiments, other circuits and methodologies are used (other exemplary detector schemes are described elsewhere) .
As discussed above with reference to FIG. 1, one of the fibers 7 measures the light source 11, which could be by means of a neutral density filter, which serves to reduce the intensity of the received light to keep the intensity approximately in the range of the other light intensities received. Three of the fibers 7 are also of the light receiving optical fibers R1 through R3 (see, eg, FIG 2) and could also pass through the neutral density filters. Such receiver fibers 7 serve to provide data from which the angle / height information and / or surface characteristics could be determined.
The remaining twelve fibers (of the total of the 16 fibers of the preferred embodiment) of the fibers 7 pass through color filters and are used to produce the color measurement. In a preferred embodiment of the invention, the color filters are Wratten Gelatine Filters Coated at Kodak Point, which pass light at wavelengths greater than the cut-off value of the filter (e.g., values tending to red) , and absorb light with wavelengths less than the cut-off value of the filter (eg, values that tend to blue). The "Cut to Tip" filters are available in a wide variety of frequency / wavelength cutoffs, and the cutoff values in general could be selected by the appropriate selection of the desired cut filter. In a preferred embodiment, the cut-off values of the filter are chosen to cover the entire visible spectrum and, in general, to have bands spaced from approximately the range of the visible band (or other desired range) divided by the number of receivers. As an example, 700 nanometers minus 400 nanometers, divided by 11 bands (produced by twelve color receivers / detectors), is approximately 30 nanometers of band space.
With an array of shear filters as described above, and without being bound by the specific theory or modalities described herein, the received optical spectrum could be measured / calculated by subtracting the light intensities of the "adjacent" light receptors. . For example, band 1 (400 nm to 430 nm) = (receiver intensity 12) minus (receiver intensity 11), and so on for the remaining bands. Such an arrangement of shear filters, and the intensity values that could result from filtering with such an arrangement, are more fully described in connection with FIGS. 13A to 14B.
It should be noted here that in alternate modes other color filter arrays are used. For example, "notch" or through-band filters could be used, such as could be developed using Schott glass type filters (either constructed from separate long-pass / short-pass filters or otherwise).
In a preferred embodiment of the present invention, the specific characteristics of the light source, filters, detectors and optical fibers, etc., are normalized / calibrated by directing the probe to, and measuring, a known color standard. Such normalization / calibration could be developed by placing the probe in a suitable fixed part, with the probe directed from a predetermined position (eg, height and angle) of the known color standard. Such results of the normalization / calibration measurement could be stored, for example, in a look-up table, and using the microprocessor 10 to normalize or correct the measured or other color results. Such procedures could be addressed at the beginning, at regular periodic intervals, or by operator command, etc.
What should be observed from the above description is that the optical fibers and the receiving and sensing circuitry illustrated in FIG. 3 provides a convenient and convenient way to determine color by measuring the intensity of light reflected from the surface of the object being measured.
It should also be noted that such a system measures the spectrum band of the light reflected from the object, and once measured such a spectrum result could be used in a variety of ways. For example, such a spectrum result could be displayed directly as intensity-wavelength values of the band. In addition, triple stimulus type values could be easily calculated (through, for example, conventional matrix mathematics), thus it could be with any other value of the desired color. In a particular embodiment useful in dental applications (such as dental prostheses), the color value is derived in the form of a matching or closer matches of the guide value of the tooth shape. In a preferred embodiment, several existing shade guides (such as shadow guides produced by Vita Zahnfabrik) are characterized and stored in a look-up table, or in the Pantone references of the graphic arts industry, and the results of the Color measurements are used to select the value or values of the closest shadow guides, which could be accompanied by a confidence level or other suitable factor that indicates the degree of matching or close matches, which include, for example, known as values of? E or ranges of values of? E, or criteria based on standard deviations, such as minimization of standard deviation. In still other embodiments, the color measurement results are used (such as search tables) to select materials for the paint composition or ceramics such as for prosthetic teeth. There are many other uses of the spectrum results measured in accordance with the present invention.
It is known that certain objects such as human teeth could fluoresce, and such optical characteristics could also be measured in accordance with the present invention. A light source with an ultraviolet component could be used to produce more accurate color / optical results with respect to such objects. In certain embodiments, a tungsten / halogen source (as used in a preferred embodiment) could be combined with a UV light source (such as a mercury vapor, xenon or other fluorescent light source, etc.) to produce a light output capable of causing the object to fluoresce. Alternatively, a separate source of UV light, combined with a filter that blocks visible light, could be used to illuminate the object. Such a UV light source could be combined with red LED light (for example) to provide a visual indication of when the UV light is on and also serves as an aid to the directional positioning of the probe operating with such a light source. A second measurement could be taken using the UV light source in a manner analogous to that described above, with the red LED band or other supplementary light source being ignored. The second measurement could thus be used to produce an indication of the fluorescence of the tooth or other object to be measured. With such a UV light source, a silica optical fiber (or other suitable material) would typically be required to transmit light to the object (standard fiber optic materials such as glass and plastic generally do not propagate the UV light in a desired way, etc.).
As described above, in certain preferred embodiments the present invention utilizes a plurality of peripheral receiving fiber optics spaced from and around the optical fiber of the central source to measure the color and determine the information that relates to the height and angle of the probe. with respect to the surface of the object to be measured, which could include other information characteristic of the surface, etc. Without being related by theory, certain principles that underline this aspect of the present invention will be described with respect to FIGS. 4A to 4C.
FIG. 4A illustrates a typical optical fiber step index consisting of a core and a coating. For this discussion, it is assumed that the core has a refractive index of n0 and the coating has a refractive index of n1. Although the following discussion is directed to the "Pass Rate" fibers, it will be apparent to those skilled in the art that such a discussion in general also applies to gradient index fibers.
To propagate light without loss, light must be incident within the fiber optic core at an angle greater than the critical angle, which could be represented as Sen-1. { ? .1 / ?. 0 } , where n0 is the refractive index of the core and nx is the refractive index of the coating. Thus, all light must enter the optical fiber at an acceptance angle equal to or less than fi, with fi = 2 x Sen-1. { v (n02 - n! 2)} , or it will not spread in a desired way.
For light entering an optical fiber, it must enter with the acceptance angle fi. Similarly, when the light leaves an optical fiber, it must exit the optical fiber in an angle cone fi as illustrated in FIG. 4A. The value V (n02-n12) is referred to as the aperture of the optical fiber. For example, . A typical optical fiber could have an aperture of 0.5, and an acceptance angle of 60 °.
Consider using an optical fiber as a light source.
One end is illuminated by a light source (such as light source 11 of FIG 1), and the other end is kept near a surface. The optical fiber will emit a cone of light as illustrated in FIG. 4A .. If the optical fiber is kept perpendicular to a surface it will create a circular light pattern on the surface. As the optical fiber goes up, the radius r of the circle will increase. As the optical fiber is lowered, the radius of the light pattern will decrease. Thus, the intensity of the light (luminous energy per unit area) in the illuminated circular area will increase as the optical fiber is lowered and will decrease as the optical fiber goes up.
In general the same principle is true for an optical fiber that is used as a receiver. Consider mounting a light detector on one end of an optical fiber and keeping the other end near the illuminated surface. The optical fiber can propagate only light without loss when the light entering the optical fiber is incident on the end of the optical fiber near the surface if the light enters the optical fiber within its acceptance angle fi. An optical fiber used as a light receiver near a surface will accept only light from the circular area of radius r on the surface. As the optical fiber rises from the surface, the area increases. As the optical fiber falls to the surface, the area decreases.
Consider two optical fibers parallel to one another as illustrated in FIG. 4B. For simplicity of discussion, the two optical fibers illustrated are identical in size and aperture. The following discussion, however, in general would be applicable for optical fibers that differ in size and aperture. An optical fiber is a source of optical fiber, the other optical fiber is a receiving optical fiber. As the two fibers remain perpendicular to a surface, the fiber optic source emits a cone of light that illuminates a circular area of radius r. The receiving optical fiber can accept only light that is within its acceptance angle fi, or only light that is received within a cone of angle fi. If only the available light is emitted by the fiber optic source, then only the light that can be accepted by the receiving optical fiber is the light that hits the surface at the intersection of the two circles as illustrated in FIG. 4C. As the two optical fibers rise from the surface, the ratio of the intersection of the two circular areas relative to the circular area of the optical fiber source increases. As they are close to the surface, the ratio of the intersection of the two circular areas relative to the circular area of the fiber optic source decreases. If the optical fibers are kept too close, the circular areas will no longer intersect and light emitted from the fiber optic source will not be received by the receiving optical fiber.
As previously discussed, the intensity of light in the circular area illuminated by the fiber source increases as the fiber is lowered to the surface. The intersection of the two cones, however, decreases as the pair the optical fiber is lowered. Thus, as the fiber optic pair is lowered to the surface, the total luminous intensity received by the receiving optical fiber increases to a maximum value, and then suddenly decreases as the fiber optic pair is further lowered to the surface. Eventually, the intensity will essentially decrease to zero (assuming that the object being measured is not transparent, as described more fully here), and will remain essentially zero until the fiber optic pair is in contact with the surface. Thus, as a receiver pair of the optical fibers as described above is positioned close to a surface and as its height is varied, the light intensity received by the receiving optical fiber reaches a maximum value at a peak or "critical height" h ~ .
It has been observed again, without being destined by the theory, an interesting property of the critical height hc. The critical height hc is an elementary function of the geometry of the set parameters, such as fiber apertures, fiber diameters and fiber spacing. Since the receiving optical fiber in the illustrated arrangement only detects a maximum value and does not attempt to quantify the value, its maximum in general is independent of the surface characteristics. It is only necessary that the surface reflects enough light from the area of intersection of the source and receiver optical fibers to be within the detection range of the light detector of the receiving optical fiber. Thus, in general red or green or blue or any other matic surface will exhibit a maximum at the same critical height hc. Similarly, smooth reflection surfaces and rough surfaces will also have intensity values that vary at the maximum value, but generally speaking all of these surfaces will exhibit a maximum at the same critical height hc,. The current value of the light intensity will be a function of the surface color and surface characteristics, but the height where the maximum intensity value in general does not occur. This is particularly true with respect to types or categories of similar materials, such as tooth, industrial objects, etc.
Although the discussion has focused on two optical fibers perpendicular to a surface, similar analysis is applicable for pairs of optical fibers at other angles.
When an optical fiber is not perpendicular to a surface, they generally illuminate an elliptical area. Similarly, the acceptance area of the receiving optical fiber in general becomes elliptical. As the fiber optic pair moves closer to the surface, the receiving fiber optic will also detect a maximum value at a critical height independent of surface color or characteristics. The maximum value of the intensity measured when the fiber optic pair is not perpendicular to the surface, however, will be less than the value of the maximum intensity measured when the fiber pair is perpendicular to the surface.
Referring now to FIGS. 5A and 5B, the received light intensity will now be described as a source pair fiber optic receiver moving to and from a surface. FIG. 5A illustrates the intensity of the light received as a function of time. Correspondingly FIG. 5B illustrates the height of the optical fiber pair of the surface of the object to be measured. FIGS. 5A and 5B illustrate (for ease of discussion) a relatively uniform speed of movement of the fiber optic pair to and from the surface of the object to be measured (although analysis / illustrations would also be applicable for non-uniform velocities).
FIG. 5A illustrates the intensity of the received light as the optical fiber moves to and from a surface. While FIG. 5A illustrates the intensity ratio for a single receiving fiber optic, similar intensity ratios would be expected to be observed for other receiver optical fibers, such as, for example, the multiple receiver optical fibers of FIGS. 1 and 2. In general with the preferred embodiment described above, the fifteen receiving optical fibers (of the fibers 7) will exhibit curves similar to those illustrated in FIG. 5A.
FIG. 5A illustrates five regions. In region 1, the probe moves towards the surface of the object to be measured, which causes the received light intensity to increase. In region 2, the probe moves past the critical region, and the peaks of received light intensity and then drops sharply. In region 3, the probe is essentially in contact with the surface of the object to be measured. As illustrated, the intensity received in region 3 will vary depending on the transparency of the object to be measured. If the object is opaque, the luminous intensity will be very low, or almost zero (perhaps outside the range of the detector circuit). If the object is transparent, however, the luminous intensity will be very high, but in general it should be less than the compensation value. In region 4, the probe rises and the light intensity increases sharply to a maximum value. In region 5, the probe also rises away from the object, and again the light intensity decreases.
As illustrated, two peak intensity values
- (discussed later as Pl and P2) should be detected as the optical fiber pair moves to and from the object at the critical height hc. If the peaks Pl and P2 produced by a receiving optical fiber are the same value, this is generally an indication that the probe has moved to and from the surface of the object to be measured in a consistent manner. If the peaks Pl and P2 are different values, then these could be an indication that the probe did not move to and from the surface of the object in a desired way, or that the surface is curved or textured, as described more fully here. In such a case, the results could be considered untrustworthy and rejectable. Furthermore, the peaks Pl and P2 for each of the perimetric optical fibers (see, eg, FIG 2) should be presented at the same critical height (assuming that the geometrical attributes of the perimetric optical fibers, such as aperture, diameter and spacing of the fiber optic source, etc.) Thus, the perimetric optical fibers of a probe moved in a consistent manner, perpendicular to and from the surface of an object to be measured should have the peaks Pl and P2 that are presented to the same critical height. Monitoring the receptor fibers from the perimeter optical fibers and looking for the simultaneous Pi and P2 peaks provides a mechanism to determine if the probe is maintained at a desired perpendicular angle with respect to the object to be measured.
In addition, the relative intensity level in region 3 serves as an indication of the level of transparency of the object to be measured. Again, in general such principles are applicable to all of the receiver optical fibers in the probe (see, eg, fibers 7 of FIGS 1 and 3). Based on such principles, the measurement techniques according to the present invention will now be described.
FIG. 6 is a flow diagram illustrating a measurement technique in accordance with the present invention. Step 49 indicates the start or start of a color / optical measurement. During step 49, any initiation, diagnostic or calibration equipment procedure could be developed. The audio or visual information or other signal could be given to the operator to inform the operator that the system is available and ready to take a measurement. The initiation of the color / optical measurement begins with the operator moving the probe towards the object to be measured, and could be performed by, for example, activation of the switch 17 (see FIG 1).
In step 50, the system on a continuous basis monitors the intensity levels for the receiving optical fibers (see, eg, fibers 7 of FIG 1). If the intensity is increasing, step 50 is repeated until a peak is detected. If a peak is detected, the process proceeds to step 52. In step 52, the intensity of the peak Pl is measured, and the time at which such compensation occurs, they are stored in the memory (such as in memory as a part of the microprocessor 10), and the process proceeds to step 54. In step 54, the system continues to monitor the intensity nodes of the receiving optical fibers. If the intensity is falling, step 54 repeats. If a "valley" or plateau is detected (eg, the intensity is no longer falling, which generally indicates contact or next contact with the object), then the process proceeds to step 56. At the stage 56, the measured surface intensity (IS) is stored in the memory, and the process proceeds to step 58. In step 58, the system continues to monitor the intensity levels of the receptor fibers. If the intensity is increasing, step 58 is repeated until a peak is detected. If a peak is detected, the process proceeds to step 60. In step 60, the measured peak intensity P2, and the time in which such compensation is presented, are stored in the memory, and the process proceeds to step 62 In step 62, the system continues to monitor the levels of the receiving optical fibers. Once the received intensity levels begin to fall from peak P2, the system perceives that region 5 has been entered (see, eg, FIG 5A), and the process proceeds to step 64.
In step 64, the system, under the control of the microprocessor 10, could analyze the results collected by the detector circuit for the different receiving optical fibers. In step 64, the peaks Pl and P2 of one or more of the different optical fibers could be compared. If any of the peaks Pl and P2 for any of the different optical fibers have different peak values, then the results could be rejected and the total measurement process repeated. Again, the unequal values of peaks Pl and P2 could be indicative, for example, that the probe moved in a non-perpendicular or otherwise unstable manner (eg, angular or lateral movement), and, for example, the peak Pl could be representative of a second point on the object. As the results are unreliable, in a preferred embodiment of the present invention, the results taken in such circumstances are rejected in step 64.
If the results are not rejected in step 64, the process proceeds to step 66. In step 66, the system analyzes the results taken from the neutral density filters receivers of each of the perimetric optical fibers (e.g. , R1 to R3 of FIG 2). If the peaks of the perimetric optical fibers do not occur at or near the same point in time, this could be indicative, for example, that the probe was not perpendicular to the surface of the object to be measured. As the non-perpendicular alignment of the probe with the surface of the object to be measured could cause unreliable results, in a preferred embodiment of the present invention, the results taken in such circumstances are rejected in step 66. In a preferred embodiment, the Simultaneous or near simultaneous compensation detection (compensation within a predetermined time range) serves as an acceptance criterion for the results, in general as perpendicular alignment is indicated by the simultaneous and near simultaneous compensation of the perimeter optical fibers . In other embodiments, step 66 includes an analysis of the peak values Pl and P2 of the perimeter optical fibers. In such modalities, the system seeks to determine whether the peak values of the perimetric optical fibers (perhaps normalized with any initial calibration result) are equal within a defined range. If the peak values of the perimetric optical fibers are within the defined range, the results could be accepted, and if not, the results could be rejected. In still other modalities, a combination of simultaneous compensation and equal values are used as acceptance / rejection criteria for the results, and / or the operator could have the capacity (such as by means of open attenuator switches 12) to control one or more of the ranges of acceptance criteria. With such capacity, the sensitivity of the system could be controllably altered by the operator depending on the particular application and the operating environment, etc.
If the results are not rejected in step 66, the process proceeds to step 68. In step 68, the color results could be processed in a desired manner to produce the output of optical / color measurement results. For example, such results could be normalized in some way, or adjusted based on temperature compensation or other data detected by the system. The results could also be converted to different representation or other formats, depending on the intended use of the results. In addition, results indicative of object transparency could also be quantified and / or represented in step 68. After step 68, the process could proceed to start stage 49, or the process could be terminated, etc.
In accordance with the process illustrated in FIG. 6, three values of luminous intensity (Pl, P2 and IS) are stored by the receiving optical fiber to make measurements of color and transparency, etc. If the stored peak values Pl and P2 are not equal (for some or all of the receivers), this is an indication that the probe does not remain stationary in one area, and the results could be rejected (in other modalities, the results could not be rejected, although results could be used to produce an average of the measured results). In addition, -the peak values Pl and P2 for the three perimeter optical fibers of neutral density should be equal or approximately equal; if this is not the case, then this is an indication that the probe is not kept perpendicular to or a curved surface to be measured. In other embodiments, the system attempts to compensate for curved surfaces and / or non-perpendicular angles. In any event, if the system can not perform a color / optical measurement, or if the results are rejected because the peak values Pl and P2 are unequal to an unacceptable degree, then the operator is notified so that another measurement or another action could be taken (such as adjusting sensitivity).
With a system built and the operation as described above, they could be taken from an object, with accepted results that have height and angular dependencies removed. The results not taken at the critical height, or the results not taken with the probe perpendicular to the surface of the object to be measured, etc., are rejected in a preferred embodiment of the present invention. In other embodiments, the results received from the perimetric optical fibers could be used to calculate the angle of the probe with respect to the surface of the object to be measured, and in such modalities the non-perpendicular or curved surface could be compensated instead of rejected. It should also be noted that the peak values Pl and P2 for the neutral density perimeter optical fibers provide a measurement of the luminescence (gray value) of the surface to be measured, and could also serve to quantify the value of the color.
The transparency of the object to be measured could be quantified as a ratio or percentage, such as, for example, (IS / PI) X 100%. In other embodiments, other methods of quantifying the results of the transparency provided in accordance with the present invention are used, such as other arithmetic functions using IS and Pl or P2, etc.
In another particular aspect of the present invention, the results generated in accordance with the present invention could be used to implement an automated mixing / generation material machine. Certain objects / materials, such as dental prostheses, are made of porcelain or other powder materials that could be combined in the correct ratios to form the desired color of the objects / prostheses. Certain powders often contain pigments that generally obey Beer's law and / or act according to the Kubelka-Munk equations and / or Saunderson's equations (if needed) when mixed in a container. The color and other results taken from a measurement in accordance with the present invention could be used to determine or predict the desired amounts of pigment or other materials for the container. Porcelain powders and other materials are available in different colors, opacities, etc. Certain objects, such as dental prostheses, could be constituted to stimulate the degree of transparency of the desired object (such as to stimulate a human tooth). The results generated in accordance with the present invention could also be used to determine the thickness and position of the porcelain or other layers of materials to more closely produce the desired color, transparency, surface characteristics, etc. In addition, based on the fluorescence results for the desired object, the container material could be adjusted to include a desired amount of fluorescent type material. In still other embodiments, the information of the surface characteristics (such as texture) (as fully described herein) could be used to add a texturizing material to the container, all of which could be carried out in accordance with the present invention.
For more information regarding such technology of the pigment type of vessel material, reference is made to: "The Measurement of Appearance," Second Edition, edited by Hunter and Harold, copyright 1981; and "Pigment Handbook," edited by Lewis, copyright 1988. All precedents are believed to have been published by John Wiley & Sons, Inc., New York, NY, and everything is incorporated here by reference.
In certain operating environments, such as dental applications, contamination of the probe belongs. In certain embodiments of the present invention, implements are provided to reduce such contamination.
FIGS. 7A and 7B illustrate a protective cap that could be used to adjust the tip end of the probe 1. Such a protective layer consists of the body 80, the end of which is covered by the optical window 82, which in a preferred embodiment consists of a structure having a fine sapphire window. In a preferred embodiment, the body 80 consists of stainless steel. The body 80 fits over the tip end of the probe 11 and could be held in place of, for example, indentations formed in the body 80, which fit with flanges 84 (which could be a spring clamp or other retainer) formed on the tip of the probe 1. In other embodiments, other methods of attaching such a protective layer to the tip of the probe 11 are used. The protective layer could be removed from the tip of the probe 11 and sterilized in a typical autoclave, steam hot, chemoclavable or other sterilization system.
The thickness of the sapphire window should be less than the critical height of the probe to preserve the ability to detect compensation according to the present invention, and preferably has a thickness less than the minimum height at which the source / receiver cones overlap (see FIGS 4B and 4C). It is also believed that sapphire windows could be produced in a reproducible manner, and thus any attenuation of light from one cover to another could be reproducible. In addition, any distortion of the color / optical measurements produced by the sapphire windows could be calibrated by the microprocessor 10.
Similarly, in other embodiments the body 80 has a lid with a hole in the center (opposite a sapphire window), with the hole positioned over the fiber optic source / receivers.
The cover with the hole serves to prevent the probe from coming into contact with the surface, which reduces the risk of contamination. It should be noted that, with such embodiments, the orifice is located so that light from the source / light receiving elements of the probe tip is not adversely affected by the cap.
FIGS. 8A and 8B illustrate another embodiment of the removable probe tip that could be used to reduce contamination according to the present invention. As illustrated in FIG. 8A, the tip of the probe 88 is removable, and includes four (or a different number, depending on the application) fiber optic connectors 90, which are positioned within an optical protection 92. The optical protection 92 serves to prevent " crosstalk "between adjacent optical fibers. As illustrated in FIG. 8B, in this embodiment the removable tip 88 is secured in the probe tip housing 92 by the spring clamp 96 (the other remaining removable tools are used in the other embodiments). The probe tip housing 92 could be secured to the base connector 94 by a screw or other conventional adjustment. It should be noted that, with this embodiment, different tip sizes could be provided for different applications, and that an initial stage of the process could be to install the appropriate sizing (or adjusted tip) for the particular application. The removable tip 88 could also be sterilized in a typical autoclave, hot steam, chemoclave or other sterilizing system, or disposed of. In addition, the assembly of the complete probe tip is constructed so that it could be easily disassembled for cleaning or repair. In certain embodiments the light source / receiver elements of the removable tip are constructed of glass, silica or other materials, so they are made particularly suitable for autoclaving or similar high temperature / pressure cleaning methods, which in certain embodiments the elements of source / light receptors of the removable tip are constructed of plastic or other similar materials, which could be of lower cost, making them particularly suitable for removable tips of the available type.
In still other embodiments, a plastic, paper or other type of protector (which could be available, cleanable / reusable or the like) could be used to address any contamination that might exist in the particular application. In such modalities, the methodology could include positioning such a protector over the tip of the probe before taking color / optical measurements, and could include removing and disposing / cleaning the protector after taking color / optical measurements, etc.
With reference to FIG. 9, a modality of triple stimulus type values of the present invention will now be described. In general, the overall system depicted in FIG. 1 and discussed in detail elsewhere could be used with this modality. FIG. 9 illustrates a cross section of the probe tip of the optical fibers used in this embodiment.
The tip of the probe 100 includes an optical fiber of the central source 106, surrounded by (and spaced apart) three perimeter receiving optical fibers 104 and three color receiving optical fibers 102. The three optical receiving optical fibers 104 are optically coupled to the Neutral density filters and serve as height / angle detectors in a manner analogous to the modality described above. The three color-receiving optical fibers are optionally coupled to filters with triple-stimulus values, such as red, green and blue filters. With this embodiment, a triple-stimulus color value measurement of the object could be made, and the process described with reference to FIG. 6 in general is applicable to this modality. In particular, the perimetric optical fibers 104 could be used to detect simultaneous compensation or otherwise if the probe is perpendicular to the object to be measured. In addition, taking color measurement results at critical height could also be used with this modality.
FIG. 10A illustrates one embodiment of the present invention, similar to the embodiment discussed with reference to FIG. 9. The tip of the probe 100 includes an optical fiber of the central source 106, surrounded by (and spaced apart) three perimeter receiver optical fibers 104 and a plurality of color receiving optical fibers 102. The number of color receiving optical fibers 102, and the filters associated with the receiver optical fibers 102, could be chosen based on the particular application. In accordance with the embodiment of FIG. 9, the process described with reference to FIG. 6 in general is applicable to this modality.
FIG. 10B illustrates an embodiment of the present invention in which there is a plurality of receiver optical fibers surrounding the optical fiber of the central source 240. The receiving optical fibers are arranged in rings surrounding the optical fiber of the central source. FIG. 10B illustrates three rings of the receiving optical fibers (consisting of optical fibers 242, 244 and 246, respectively), in which there are six receiver optical fibers per ring. The rings could be arranged in successive larger circles as illustrated to cover the entire area of the end of the probe, with the distance of each receiving optical fiber within a given ring to the central optical fiber that is equal (or approximately). The central optical fiber 240 is used as the optical fiber of the light source 5 is illustrated in * FIG. 1.
The plurality of the receiving optical fibers each are coupled to two or more optical fibers in a manner similar to the arrangement illustrated in FIG. 1 for the junction connector 4. An optical fiber of such junction connector of each receiving optical fiber passes through a neutral density filter and then into the light detector circuit similar to the light detector circuit illustrated in FIG. 3. A second optical fiber of the receiver fiber optic junction connector passes through a Wrattan Cut-to-Point Gelatine Filter and then to the light sensor circuit as discussed elsewhere elsewhere. In this way, each of the optical fibers receiving at the tip of the probe includes elements for measuring color and measuring neutral light or "perimetric" elements.
FIG. 10D illustrates the geometry of the probe 260 (as described above) which illuminates an area on the diffuse flat surface 272. The probe 260 creates the light pattern 262 that diffusely reflects from the surface 272 in the uniform hemispherical pattern 270. With such a reflection pattern, the reflected light that is incident on the receiving elements in the probe will be equal (or nearly equal) to all the elements if the probe is perpendicular to the surface as described here above.
FIG. 10C illustrates a probe that illuminates the rough surface 268 or a surface that reflects light spectrally. The reflected spectral light will exhibit hot spots or regions where the reflected light intensity is considerably higher than on the other areas. The pattern of reflected light will be non-uniform when compared to a smooth surface as shown in FIG. 10D.
Since a probe as illustrated in FIG. 10B has a plurality of receiver optical fibers arranged over a large surface area, the probe could be used to determine the surface texture of the surface as well as being able to measure the color and transparency, etc., of the surface described above. If the luminous intensity received by the receiving optical fibers is the same for all the optical fibers within a given ring of receiving optical fibers, then in general the surface is diffuse and smooth. If, however, the luminous intensity of the receptor fibers in one ring varies with respect to each other, then in general the surface is rough or spectral. By comparing the luminous intensities measured within the receiver optical fibers in a given ring and from ring to ring, the texture and other characteristics of the surface could be quantified.
FIG. 11 illustrates an embodiment of the present invention in which linear optical detectors and a chromatic gradient filter are used in place of light detectors 8 (and filters 22, etc.). The receiver optical fibers 7 that could be optically coupled to the tip of the probe 1 as with the embodiment of FIG. 1, are optically coupled to the linear optical detector 112 through the color gradient filter 110. In this embodiment, the color gradient filter 110 may consist of strips of narrow strips of cut type filters on a transparent or open substrate, which it is constructed to correspond positionally to the areas of the linear optical detector 112. An example of a commercially available linear optical detector 112 is Texas Instruments part number TSL 213, which has 61 photodiodes in a linear array. The light-receiving optical fibers 7 are correspondingly arranged in a line on the linear optical detector 112. The numbers of the receiving optical fibers could be chosen for the particular application, enough so much as they are included to cover more or less uniformly the full length of the optical fiber. color gradient filter 110. With this embodiment, light is received and output from the receiver optical fibers 7, and the light received by the linear optical detector 112 is integrated for a short period of time (determined by the light intensity, characteristics of the filter and the desired accuracy). The output of the line array detector 112 is digitized by ADC 114 and output to the microprocessor 116 (which could be the same processor as a microprocessor 10 or another processor).
In general with the embodiment of FIG. 11, the perimetric receiver optical fibers could be used as in the embodiment of FIG. 1, and in general the process described with reference to FIG. 6 is applicable to this modality.
FIG. 12 illustrates one embodiment of the present invention in which an optical matrix detector and the chromatic filter grid are used in place of the light detectors 8 (and filters 22, etc.). The receiver optical fibers 7, which could be optically coupled to the tip of the probe 1 as with the embodiment of FIG. 1, optically coupled to the array optical detector 122 through the filter grid 120. The filter grid 120 is an array of filters consisting of a number of small color dot filters passing through the narrow bands of light visible. The light from the receiving optical fibers 7 passes through the corresponding points of the filter to the corresponding points in the optical array detector 122. In this embodiment, the optical array detector 122 could be a monochromatic optical detector array, such as CCD type or other type of light detector element such as could be used in a video camera. The output of the optical array detector 122 is digitized by an ADC 124 and output to the microprocessor 126 (which could be the same processor as a microprocessor 10 or another processor). Under the control of the microprocessor 126, the optical array detector 126 collects the results of the receiving optical fibers 7 through the color filter grid 120.
In general, with the embodiment of FIG. 12, the perimetric receiver optical fibers could be used as with the embodiment of FIG. 1, and in general the processes described with reference to FIG. 6 is also applicable to this modality.
As will be apparent from the above description, with the present invention a variety of types of color / optical spectrum photometers (or triple-stimulus type colorimeters) could be constructed, with the perimeter receiving optical fibers used to collect color results. / optics essentially free of height and angle deviations. In addition, in certain embodiments, the present invention allows color / optical measurements taken at a critical height from the surface of the object to be measured, and thus the color / optical results could be taken without physical contact with the object being removed. to be measured (in such embodiments, color / optical results are taken only by passing the probe through region 1 and within region 2, but not necessarily within region 3 of FIGS 5A and 5B) Modalities could be used if contact with the surface is undesirable in a particular application. In the embodiments described above, however, physical contact (or close physical contact) of the probe with the object could allow the five regions of FIGS. 5A and 5B to be used, thus allowing to obtain also the measurements to be taken such information or transparency. In general, both types of modalities are within the scope of the invention described herein.
The additional description will now provide with respect to cut-off filters of the types described in connection with the preferred embodiment (s) of FIGS. 1 and 3 (such as the filters 22 of FIG 3). FIG. 13A illustrates the properties of a simple Koratk Cut Wratten Gelatine Filter discussed in connection with FIG. 3. Such a cut filter passes light below a cutoff frequency (eg before a cut-off wavelength). Such filters could be manufactured to have a wide range of cutting frequencies / wavelengths. FIG. 13B illustrates a number of such filters twelve in a preferred embodiment, with frequencies / cut-off wavelengths being chosen so that essentially the entire visible band is covered by the collection of cut-off filters.
FIGS. 14A and 14B illustrate exemplary intensity measurements using an ordered cut filter as illustrated in FIG. 13B, first in the case of a white surface to be measured (FIG 14A), and also in the case of a blue surface to be measured (FIG 14B). As illustrated in FIG. 14A, in the case of a white surface, the neutrally filtered perimeter optical fibers that are used to detect height and angle, etc., will generally produce the highest intensity (although this depends at least in part on the characteristics of the filters of neutral density). As a result of the stepper filtration provided by the filters having the characteristics illustrated in FIG. 13B, the remaining intensities will gradually decrease in value as illustrated in FIG. 14 TO. In the case of a blue surface, the intensities will generally decrease in value as illustrated in FIG. 14B. Regardless of the surface, however, the output intensities of the filters will always decrease in value as illustrated, with the higher intensity value being the filter output having the lowest cut-off wavelength value (eg, it passes all visible light to blue), and the value of the lowest intensity that is the output of the filter that has the highest cut-off wavelength (eg, passes only visible light). red). As will be understood from the foregoing description, any detected color result that does not conform to the intensity decrease profiles of FIGS. 14A and 14B could be detected as an abnormality, and in certain detection modalities such a condition results in the rejection of the results, generation of an error message or initiation of a diagnostic routine, etc.
The reference should be made to FIGS. 1 and 3 and the related description of a detailed discussion of how such a cut filter arrangement could be used in accordance with the present invention.
FIG. 15 is a flow diagram illustrating the audio tones that could be used in certain preferred embodiments of the present invention. It has been found that audio tones (such as tones, ring tone, voice or the like as will be described) particularly present a useful and instructive means for guiding an operator in the proper use of the color measurement system of the type here. described.
The operator could initiate a color / optical measurement by activating a switch (such as switch 17 of FIG.1) in step 150. After this, if the system is ready (fixed, initialized, calibrated) , etc.), a tone from the lowest probe is emitted (such as through a loud voice 16 of FIG. 1) in step 152. The system attempts to detect the peak intensity Pl in step 154. If detect a peak, in step 156 a determination is made if the measured peak Pl satisfies the applicable criterion (as discussed above in connection with FIGS 5A, 5B and 6) if the measured peak Pl is accepted, a acceptance tone of. first peak in step 160. If the measured peak is not accepted, an unsuccessful tone is generated in step 158, and the system could wait for the operator to initiate an additional color / optical measurement. Assuming that the first peak was accepted, the system attempts to detect the intensity of peak P2 in step 162. If a second peak is detected, a determination is made in step 164 if the measured peak P2 satisfies the applicable criterion. If the measured peak P2 is accepted the process proceeds to the color calculation step 166 (in other embodiments, an acceptance tone of the second peak is also generated in step 166). If the measured peak P2 is not accepted, an unsuccessful tone is generated in step 158, and the system could wait for the operator to initiate a color / optical measurement. Assuming that the second peak was accepted, a color / optical calculation is made in step 166
(such as, for example, the microprocessor 10 of FIG 1 which processes the output results of the light detectors 8 etc.). In step 168, a determination is made if the color calculation satisfies the applicable criteria. If the color calculation is accepted a successful tone is generated in step 170. If the color calculation is not accepted an unsuccessful tone is generated in step 158, and the system could wait for the operator to start a color measurement / optics.
With unique audio tones presented to an operator according to the particular operating state of the system, the use of the system operator could be greatly facilitated. Such audio information also tends to increase operator satisfaction and improve level, as, for example, acceptance tones provide positive and encouraging feedback when the system is operated in a desired manner.
The optical / color measuring systems and methods according to the present invention could be applied to the particular advantage in the field of dentistry, as will be explained more fully below. In particular, the present invention includes the use of such systems and methods for measuring the color and other attributes of a tooth to prepare a dental prosthesis or intraoral tooth-colored fillings, or to select the denture or to determine a cement color suitable for a prosthesis. porcelain / resin. The present invention also provides methods for storing and organizing measured results such as in the form of a patient database.
FIG. 16 is a flow diagram illustrating a general dental application process flow for use of the color / optical measurement systems and methods according to the present invention. In step 200, the color / optical measurement system could be strengthened and stabilized, with some required initialization or other fixed routines executed. In step 200, an indication of the state of the system could be provided to the operator, such as through LCD 14 or loudspeaker 16 of FIG. 1 also in step 200, the tip of the probe could be covered or a tip of the clean probe could be inserted to reduce the likelihood of contamination (see, eg, FIGS 7A to 8B and related description). In other embodiments, a plastic or other protection (which could be available, cleanable / reusable, etc., as described above) could also be used, as long as it is constructed and / or positioned so as not to adversely affect the measurement process.
In step 202, the patient and the tooth to be measured are prepared. Any required cleaning or other preparation of the tooth would be performed in step 202. Any required patient consultation about the type of prosthesis or area of a tooth to be paired would be performed at (or prior to) step 202. In certain embodiments , a positioning device is prepared in step 202 as illustrated in FIGS. 17A and 17B. In such embodiments, for example, a black material or other suitable color 282, which could be adhered to the tooth 280 (such as with an appropriate adhesive), is formed to have the opening 281 larger than the diameter of the measuring probe, with opening 281 centered in the area of tooth 280 to be measured. The material of the positioning device 282 is formed in a manner to fit in / on the tooth 280 (such as on the incision edge of the tooth 280 and / or on one or more adjacent teeth) so as to be able to be placed in / on the tooth 280 in a repeatable manner. Such a positioning device can serve to ensure that the desired area of tooth 280 is measured, and also allows repeating measurements of the same area for confirmation purposes or the like. Any other pre-measurement activity could be done at (or before) step 202.
In step 204, the operator (typically a dentist or other dental professional) moves the probe to the area of the tooth to be measured. This process is preferably conducted according to the methodology described with reference to FIGS. 5A, 5B and 6, and preferably it is accompanied by audio tones as described with reference to FIG. 15. With the present invention, the operator could obtain color and transparency results, etc., for example, from a desired area of the tooth to be measured. During step 204, an acceptable color / optical measurement is made, or some indication is given to the operator that the measurement step needs to be repeated or some other action taken. After an acceptable color / optics measurement is made in step 204, for example, the dentist could operate on the desired tooth or teeth or take another action. Before or after such action, additional measurements may be taken as necessary (see, eg, FIG.18 and related description).
In the successful completion of one or more measurements taken in step 204, the process continues in step 206. In step 206, any conversion or processing of results of the results collected in step 204. could be performed. For example in the mode of FIG. 1, detailed information about the color spectrum and transparency could be generated. In a particular dental application, however, it could be that a dental laboratory, for example, requires that the color be presented in Munsell format (eg, chroma, hue and value), RGB values, XYZ coordinates, CIELAB values , Hunter values, or some other color result formats. With the spectrum / color information produced by the present invention, the results could be converted to such formats through conventional matrix mathematics, for example. Such mathematics could be done by a microprocessor 10 or computer 13A of FIG. 1, or in some other way. It should also be noted that, in certain embodiments, the results produced in step 204 according to the present invention could be used directly without the conversion of results. In such embodiments, step 206 could be omitted. In other embodiments, step 206 consists of the result format, such as the preparation of results for reproduction in hard copy, pictorial or other form, or for transmission as facsimile or modem results. Finally, in certain modalities, a transparency factor is computerized in a format suitable for the particular application. Even in other modalities, a surface texture or detail factor is computerized in a format suitable for the particular application.
In step 208, an equalization is optionally attempted between the results produced in steps 204 and 206 (if performed) and a desired color (in other embodiments, the process could proceed from 204 directly to 210, or alternatively the steps could be combined 206 and 208). For example, a number of "shadow guides" are available in the market, some of which are known in the industry as Vita shadow guides, Bioform shade guides or other standards, color matching guides or references or guides. common shadows. In certain preferred embodiments, a lookup table is prepared and loaded into the memory (such as memory associated with the microprocessor 10 or computer 13A of FIG. 1), and an attempt is made for the closest match or equalization of the results. collected with known shade guides, common shadow guides or reference values. In certain embodiments, a transparency factor and / or a surface texture or detail factor is also used in an effort to select the best possible match.
In a particular aspect of certain embodiments of the present invention, a correlation material is entered into the search table in step 208. Based on the color and transparency results obtained in step 204, a proposed materials recipe, pigments or other instructional information is prepared for a prosthesis or embossment, etc., of the desired color and transparency, etc. With the detailed color and other information made available in accordance with the present invention, a direct correlation could be made with the relevant constituent materials. In yet other embodiments, such information is made available for an automated mixing or manufacturing machine for the preparation of prostheses or material of the desired color and transparency, etc., as more fully described elsewhere herein.
In step 210, based on the results of the previous steps, the prosthesis, denture, intraoral tooth-colored filling material or other articles are prepared. This step could be performed in a dental laboratory, or, in certain modalities, in or near the dental operator. For remote preparation, the relevant results produced in steps 204, 206 and / or 208 could be sent to the remote laboratory or be provided by hard copy, facsimile, or modem or other transmission. What should be understood from the above is that, based on results collected in step 204, a prosthesis could be prepared from a desired color and / or other optical characteristic in step 210.
In step 212, the prosthesis or other material prepared in step 210 could be measured for confirmation purposes, preferably conducted again according to the methodology described with reference to FIGS. 5A, 5B and 6, and preferably accompanied by audio tones as described with reference to FIG. 15. A re-measurement of the tooth in the patient's mouth, etc. It could also be done in this step for confirmation purposes. If the confirmation process gives satisfactory results, the prosthesis, denture, composite fill or other material could be installed or preliminarily applied to the patient in step 214. In step 216, a re-measurement of the prosthesis, denture could optionally be made , composite fill or other materials. If the results of step 216 are acceptable, then the prosthesis could be installed or applied more permanently to the patient in step 218. If the results of step 216 are not acceptable, the prosthesis could be modified and / or another step repeated as appropriate. necessary in the particular situation.
In another particular aspect of the present invention, for example, the processing of results as illustrated in FIG. 18 could be taken in conjunction with the process of FIG. 16. In step 286, the client's database program is run in a computing device, such as computer 13A of FIG.l. Such a program could include record of each patient's results, including fields that store the history of dental services performed on the patient, information that refers to the condition or condition of the patient's teeth, billing, address and other information. Such a program could enter a mode by which it is in a condition to accept color results or others taken in accordance with the present invention.
In step 288, for example, the dentist or other dental professional could select parameters of a particular tooth of the patient to be measured. Depending on the size and condition of the tooth (such as chromatic gradient or the like), the dentist could section the tooth in one or more regions, such as a grid. Thus, for example in the case of the tooth for which it is decided to take four measurements, the tooth could be divided into four regions.
Such parameters, which could include a pictorial representation on the computer of the tooth sectioned into four regions (such as by grid lines), along with tooth identification and patient information could be entered into the computer at this time.
In step 290, one or more measurements of the tooth could be "taken, such as a system" and method as described in connection with FIGS. 1, 5A, and 5B and / or 6. The number of such measurements are preferably associated with the parameters introduced in step 288. Subsequently, in step 292, the results collected from the measurement (s) could be sent to the computer for subsequent processing. As an illustrative example, four color / optical measurements could be taken (for the four regions of the tooth in the previous example) and sent to the computer, with the results of the four color / optical measurements (such as RGB or other values) associated with the four regions according to the parameters introduced. Also as an example, the displayed pictorial representation of the tooth could have overlaying results of the same indicative color / optical measurements. In step 294, such as after finishing the color / optical measurements in the particular patient, the results collected during the process could be stored associatively as a part of the patient's dental records in the database. In modalities accompanied by the use of an intraoral camera, for example (see, eg, FIG.19 and related description), images captured from one or more of the patient's teeth could also be stored associatively as a part of the records dental of the patient. In certain embodiments, a photograph taken by the intraoral camera is passed overhead with the grid or sector lines (such as could be defined in step 288), with measurements of color results or others as described here going through above also the captured image. In this way, the color or other results could be associated electronically and visually with a photograph of the particular measured tooth, thus facilitating the use of the system and the sub-understanding of the results collected. In still other embodiments, all captured images and color measurement records include a time and / or date, so that a record of the particular history of a particular tooth of a particular patient can be maintained. See FIGS. 24-26 and the related description for additional modalities using an intraoral camera, etc., according to the present invention.
In yet another particular aspect of the present invention, a measuring device and method (as described elsewhere herein) could be combined with an intraoral camera and other implements. As illustrated in FIG. 19, the control unit 300 contains electronics and conventional circuits, such as power supplies, electronic controls, light sources and the like. Coupled to the control unit 300 is the intraoral camera 301 (for viewing and capturing images of a patient's tooth or mouth, etc.), the healing light 302 (such as intraoral healing material for light healing), the measuring device 304 (as described elsewhere herein) and visible light 306 (which could be an auxiliary light for intraoral examinations and the like). With such embodiments, color, transparency, fluorescence, surface texture and / or other results collected for a particular tooth of the measuring device 304 could be combined with images captured by the intraoral camera 301, with complete examination and patient processing facilitated by having the measuring device 304, the intraoral camera 301, the healing light 302 and the visible light 306 integrated into a single unit. Such integration serves to provide synergistic benefits in the use of the instruments, while also reducing costs and saving physical spaces. In another particular aspect of such embodiments, the light source is divided for measurement devices 304 and intraoral camera 301, thus resulting in additional benefits.
Additional embodiments of the present invention will now be described with respect to FIGS. 20 to 23. In general, the modalities described previously have movement of the probe with respect to the object / tooth to be measured. While such modalities provide great utility in many applications, in certain applications, such as robotics, industrial control, automated manufacturing, etc. (such as positioning the object and / or the probe that will be in proximity to each other, detecting the object's color / optical properties, and then directing the object, eg, separating, based on the color properties / detected optics, for additional industrial processing, packaging, etc.) it may be desirable to have the measurement made with the probe maintained or positioned substantially stationary above the surface of the object to be measured (in such embodiments, the positioned probe could not be maintained by hand as other certain modalities). Such modalities could also have applicability in the field of dentistry (in such applications, in general the "object" refers to teeth, etc.).
FIG. 20 illustrates such additional mode. The probe of this embodiment includes a plurality of perimeter detectors and a plurality of color detectors coupled to receivers 312-320. The color detectors and related components, etc., could be constructed to operate in a manner analogous to the modalities previously described. For example, fiber optic cables or the like could couple the light from the source 310 that is received by the receivers 312-320 for net-cut filters, with the measurement of the received light over precisely defined wavelengths (see, p. eg, FIG 1, 3 and 11-14 and related description). The color / optical characteristics of the object could be determined by the plurality of measurements of the color detector, which could include three such detectors in the case of a triple-stimulus type instrument, or 8, 12, 15 or more detectors color for a more complete broadband system (the precise number could be determined by the desired color resolution, etc.).
With this embodiment, a relatively large number of perimeter detectors are used (as opposed, for example, to the three perimeter detectors used in certain preferred embodiments of the present invention). As illustrated in FIG. 20, a plurality of triads of receivers 312-320 coupled to the perimeter detectors are used, where each triad in the preferred embodiment consists of three optical fibers positioned at an equal distance from the light source 310, which in the preferred embodiment is a fiber central optics of light source. The triads of the perimeter receivers / detectors could be configured as concentric rings of detectors around the central optical fiber of the light source. In FIG. 20, ten of lime triad rings are illustrated, although in other embodiments a smaller or larger number of triad rings could be used, depending on the desired accuracy and range of operation, as well as costly and similar considerations.
The probe illustrated in FIG. 20 could be operated within a range of heights (eg, distances of the object to be measured). As with the previous modalities, such height characteristics are determined initially by the geometry and constituent materials of the probe, with the spacing of the minimum of perimeter detector rings determining the minimum height, and the spacing of the maximum number of perimeter detector rings that determine the maximum height, etc. It is therefore possible to build the probes of various ranges of height and precision, etc., by varying the number of rings of perimeter detectors and the range of ring distances of the optical fiber of the central source. It should be noted that such modalities could be suitable particularly when similar types of materials are measured, etc.
As described above, the light receiving elements of the plurality of peripheral receivers / detectors could be individual elements such as Texas Instruments TSL 230 frequency light converters, or they could be constructed with rectangular arrangement elements or the like as it could be in a camera. of CCD. Other types of broad band light measuring elements are used in other modalities. Given the large number of perimeter detectors used in such embodiments (such as 30 of the embodiment of FIG.16), an arrangement such as CCD camera type detection elements could be desired. It should be noted that the absolute intensity levels of light measured by the perimeter detectors is not as critical for such embodiments of the present invention; in such modalities the differences between the triads of perimeter light detectors are profitably used to obtain optical measurements.
Optical measurements could be made as long as the probe is holding / positioning the probe near the surface of the object to be measured (eg, within the range of acceptable heights of the particular probe). The light source that provides light to the light source 310 is turned on and the reflected light received by the receivers 312-320 (coupled to the perimeter detectors) is measured. The light intensity of the rings of the triad detectors is compared. In general, if the probe is perpendicular to the surface and the surface is flat, the light intensity of the three detectors of each triad should be approximately equal. If the probe is not perpendicular to the surface or if the surface is not flat, the light intensity of the three detectors in the triad will not be the same. Thus it is possible to determine if the probe is perpendicular to the measured surface, etc. It is also possible to compensate for non-perpendicular surfaces by mathematically adjusting the measurements of the light intensity of the color detectors with the variance in the measurements of the triads of the perimeter detectors.
While the three detectors forming the triad of detectors are at different distances (radii) from the central light source 310, it is expected that the light intensities measured by the light receivers 312-320 and the perimeter detectors will vary. For any given triad of detectors, as the probe moves closer to the surface, the received light intensity will increase to a maximum and then sharply decrease as the probe moves closer to the surface. As with the modalities described previously, the intensity decreases rapidly as the probe moves less than the critical height and decreases rapidly to zero or near zero for opaque objects. The value of the critical height depends mainly on the distance of the particular receiver of the light source 310. Thus, the detector triads will have peaks at different critical heights. By analyzing the variation in the light values received by the triad of detectors, the height of the probe can be determined. Again, this is particularly true when measuring similar types of materials.
Initially the system is calibrated against a neutral background (eg, gray background), and the calibration values are stored in non-volatile memory (see, eg, processor 10 of FIG. 1). For any given color or intensity, the intensity for the perimeter receivers / detectors (regardless of the distance of the optical fiber from the central source) should generally vary equally. Therefore, a white surface must produce the highest intensities for the perimeter detectors, and a black surface will produce the lowest intensities. Although the color of the surface will affect the intensities of the measured light of the perimeter detectors, it should affect them substantially the same. The height of the probe on the surface of the object, however, will affect differently the triads of the detectors. In the minimum height range of the probe, the triad of detectors in the smallest ring (those closest to the optical fiber of the source) will be at or approximately their maximum value. The rest of the rings of the triad will measure light at intensities lower than their maximum values. As the probe rises / positions from the minimum height, the intensity of the smaller ring of the detectors will decrease and the intensity of the next ring of detectors will increase to its maximum value and then decrease in intensity as the probe rises / positions still plus. Similarly for the third ring, fourth ring and so on. Thus, the pattern of intensities measured by the triad rings will depend on the height. In such modalities, the characteristics of this pattern could be measured and stored in non-volatile RAM (or similar) search tables for the probe calibrating in a fixed part using a neutral color surface. Again, the actual intensity of light is not as important in such modalities, but the degree of variation from one ring of perimeter detectors to another if it is.
To determine a measurement of the height of the probe from the surface to be measured, the intensities of the perimeter detectors (coupled to receivers 312-320) are measured. The variation in the light intensity of the inner ring of the perimeter detectors to the next ring, etc., are analyzed and compared in the search table to determine the height of the probe. The determined height of the probe with respect to the surface could thus be used by the processor system to compensate for the light intensities measured by the color detectors to obtain reflection readings that are generally independent of height. As in the previously described embodiments, the reflection measurements could then be used to determine the optical characteristics of the object to be measured, etc.
It should be noted that audio tones, as previously described, could be advantageously employed when such modality is used in a manual configuration. For example, the audio tones of pulses that vary, frequencies and / or intensities could be used to indicate the operational status of the instrument, when the instrument is positioned within an acceptable range for color measurements, when measurements have been taken. Valid or invalid colors, etc. In general, audio tones as previously described could be adapted to advantageously use such additional modalities.
FIG. 21 illustrates such additional embodiment of the present invention. The preferred implementation of this embodiment consists of a central light source 310 (which in the preferred implementation is an optical fiber of the central light source), surrounded by a plurality of receiver lights 322 (which in the preferred implementation consists of three fibers). optical receiving light perimeter). The three optical fibers receiving perimetric light, as in the modalities described above, could each be put together within the additional optical fibers that pass to the light intensity receptors / detectors, which could be implemented with frequency converters Texas Instruments TLS 230 as previously described. A fiber of each perimeter receiver is coupled to a detector and the entire wide band is measured (or substantially over the same wide band) such as via a neutral density filter, and other fibers of the perimeter receivers are They couple detectors in such a way that the light passes through the sharp or notch cut filters to measure the intensity of light over different ranges of light frequency (again, as in the modalities described above). There are color light detectors and neutral "perimeter" detectors as in the previously described modes. The color detectors are used to determine the color or other optical characteristics of the object, and the perimeter detectors are used to determine whether the probe is perpendicular to the surface and / or are used to compensate at non-perpendicular angles within certain angular ranges. .
In the embodiment of FIG. 21., the angle of the optical fibers of the perimetric detector is mechanically varied with respect to the optical fiber of the central source. The angle of the perimeter receivers / detectors with respect to the optical fiber of the central source is measured and used as described hereinafter. An example of the mechanical mechanism, the details of which are not critical as much as desired, the control of movement of the perimeter receivers with respect to the light source is obtained, is described with reference to FIG. 22
The probe is kept within the usual range of the instrument (determined by the particular configuration and construction, etc.), and a color measurement is initiated. The angle of the perimeter receivers / detectors with respect to the central light source is varied from parallel to sharp with respect to the optical fiber of the central source. While the angle is varied, the intensities of the light detectors of the perimeter detectors (eg, neutral detectors) and the color detectors are measured and stored along with the angle of the detectors at the moment of the light measurement. The light intensities are measured over a range of angles. As the angle increases, the light intensity will increase to a maximum value and then decrease as the angle increases more. The angle where the light values are at a maximum is used to determine the height of the probe from the surface. As will be apparent to those skilled in the art based on the techniques provided herein, with suitable calibration results, simple geometry could be used to calculate the height based on the results measured during the variation of the angle. The height measurement could then be used to compensate for the intensity of the color / optical measurements and / or used to normalize the color values, etc.
FIG. 22. illustrates an exemplary embodiment of a mechanical arrangement for adjusting and measuring the angle of the perimeter detectors. Each receiver / detector 322 is mounted with a pivot arm 326 on the structure of the probe 328. The pivot arm 236 adjusts the central ring 332 in a manner that forms a cam mechanic. The central ring 332 includes a cavity that holds a portion of the pivot arm 326 with the cam mechanism. The central ring 332 could move perpendicular with respect to the structure of the probe 328 via the linear driver 324 and the slotted thread 330. The position of the central ring 322 with respect to the linear driver 324 determines the angle of the peripheral receivers / detectors 322 with respect to the light source 310. Such results of the angular position versus the position of the linear driver 324 could be precalibrated and stored in non-volatile memory, and then used to produce color / optical characteristics measurements results. as previously described.
A further embodiment of the present invention utilizing an alternating removable probe tip will now be described with reference to FIGS. 23A-23C. As illustrated in FIG. 23A, this embodiment utilizes a removable coherent light conduit 340 as a removable tip. The light conduit 340 is a short segment of a light conduit that could preferably be a fused bundle of small optical fibers, in which the fibers remain essentially parallel to one another, and the ends of these are highly polished. The cross section 350 of the light conduit 340 is illustrated in FIG. 23B. Light conduits similar to light conduit 340 have been used in what are known as extended holes, and also be used in medical applications such as endoscopies.
The light conduit 340 in this mode serves to conduct light from the light source to the surface of the object to be measured, and also to receive light reflected from the surface and conduct it to the light receiving optical fiber 346 in the manual probe 344. The light conduit 340 is held in position with respect to the optical fibers 346 in this way or by pressure clamps 342 or other suitable fitting or coupling which securely positions the light conduit 340 to effectively couple the light towards / from the optical fiber 346. The optical fibers 346 could be separated within the separate fiber / light conduits 348, which could be coupled to the appropriate light detectors, etc., as in the previously described embodiments.
In general, the aperture of the optical fibers used in the light conduit 340 could be chosen to equalize the aperture of the optical fibers of the light source and the light receptors. Thus, the central part of the light conduit could conduct light from the light source and illuminate the surface as if it constituted a simple fiber within a bundle of fibers. Similarly, the outer portion of the light conduit could receive reflected light and conduct it towards the light receiving optical fibers as if they constituted simple fibers. The light conduit 340 has ends that are preferably highly polished and cut perpendicularly, particularly the light end coupled to the optical fibers 346. Similarly the end of the optical fibers 346 which supports the light conduit 340 is also highly polished and cut perpendicular to a high degree of accuracy to minimize light reflection and crosstalk between the optical fiber of the light source and the light of the receiving optical fibers and between the adjacent optical receiver fibers. The light conduit 340 offers significant advances that are included in the manufacture and installation of such a removable tip. For example, the tip of the probe needs not to be particularly aligned with the tip of the clamping probe; rather, it only needs to be held against the probe tip holder such as in a compression mechanism (such as in pressure clips 342) to effectively couple light to / from optical fibers 346. ThusSuch a removable tip mechanism could be implemented without the alignment clamps or the like, thus facilitating the easy installation of the removable probe tip. Such an easy-to-install probe tip could thus be removed and cleaned before installation, thus facilitating the use of the color / optical measuring device for dentists, medical professionals or other workers in the environment in which contamination might be of interest. . The light conduit 340 could also be implemented, for example, as a small section of the light conduit, which could facilitate and lower the cost of mass production and the like.
An additional embodiment of such a probe tip of a light conduit is illustrated as light conduit 352 in FIG. 23C. The light conduit 352 is a light conduit that is narrower than one end (end 354) than the other end (end 356). The profiled / conical light conduits such as the light conduit 352 could be manufactured by heating and stretching the bundle of small optical fibers as part of the melting process. Such light conduits have an additional interesting property of magnification or reduction. Such a phenomenon results because they are the same numbers of fibers at both ends. Thus, the narrow end of light entering 354 is led to a wider end 356, and since the wider end 356 covers a larger area, which has a magnifying effect.
The light conduit 352 of FIG. 23C could be used in a similar manner for light conduit 340 (which in general could be cylindrical) of FIG. 23A. The light conduit 352, however, measures smaller areas due to its reduced size at the end 354. Thus, a relatively larger probe body could be fabricated where the optical fiber of the source is widely spaced from the optical fibers receptors, which could provide an advantage in reduced light reflection and crosstalk at the junction, while still maintaining a small area of the measurement probe. Additionally, the relative sizes of the narrow end 354 of the light conduit 352 could be varied. This allows the operator to select the size / characteristic of the removable probe tip according to the conditions in the particular application. Such ability to select probe tip sizes provide an additional advantage in performing measurements of optical characteristics in a variety of applications and operating environments.
As should be apparent to those skilled in the art from the point of view of the expositions here, the light conductors 340 and 356 of FIGS. 23A and 23C do not necessarily need to be cylindrical / conical as illustrated, but could be curved such as for special applications, where a curved probe tip (such as a confined or elusive location) can be advantageously employed. It should also be evident that the light conduit 352 of FIG. 23C could be inverted (with the narrow end 354 that couples the light inside the optical fibers 346, etc., and wide end 356 positioned to take measurements) to cover larger areas.
Referring now to FIG. 24, a further embodiment of the present invention will be explained.
The 380 intrao reflectometer that could be constructed as described above, includes the probe 381. The output of the results of the reflectometer 380 is coupled to the computer 384 on the busbar (which could be a standard or parallel busbar, etc.). ). Computer 384 includes a video frame capacity frozen and preferably a modem. Intraoral camera 382 includes handpieces 383 and couples video results to computer 384 on bus 392. Computer 384 is coupled to remote computer 386 via telecommunication channel 388, which could be a standard telephone line , ISDN line, a LAN or WAN connection, etc. With such modality, video measurements could be taken by intraoral camera 382 of one or more teeth, together with the optical measurements taken by intraoral reflectometer 380. Computer 384 could still store pictures of images taken from the intraoral camera outlet 382 .
Teeth are known to have variations in color from tooth to tooth, and teeth are known to have variations in color over the area of a tooth. The intraoral cameras are known to be used showing the details of the tooth. Intraoral cameras, however, generally have poor color reproducibility. This is due to variations in the camera's detection elements (from camera to camera and over time etc.), in computer monitors, printers, etc. As a result of such variations, it is currently not possible to accurately quantify the color of a tooth with an intraoral camera. In the present embodiment, the measurement and quantification of color or other optical properties of the tooth could be simplified through the use of an intraoral reflectometer according to the present invention, together with an intraoral camera.
According to this modality, even the dentist could capture a picture of the tooth and its adjacent teeth using the frozen picture feature of the computer 384.
The computer 384, according to the appropriate program and control operator, could "freeze" after the image of the tooth and its adjacent teeth, such as limiting the number of gray levels of the light signal, which can result in a color image that shows contours of adjacent color boundaries. As illustrated in FIG. 25, such a freezing process could result in tooth 396 which is to be divided into regions 398, which follow the color contours of tooth 396. As illustrated, in general the boundaries will be irregular in shape and follow the variations of Various colors found in the particular tooth.
With the freezing of the tooth as illustrated in FIG.
, the computer 384 could then have high light points (such as a colored border, shading, bright spots or the like) a particular color region on a tooth to be measured, and then the dentist could then measure the region of bright spots with intraoral reflectometer 380. The output of the infraoral reflectometer 380 is the input to the computer 384 and over the busbar 390, and the computer 384 could store the color results in memory or on a hard disk or other storage medium. optics associated with the region of bright spots. Then the computer 384 could illuminate another region with high light and continue the process until the color / optical results associated with all the desired bright spot regions have been stored in the computer 384. Such color / optical results could then be stored in an adequate database, together with the video image and the frozen video image of the particular tooth, etc.
The computer 384 could then evaluate whether the measured value of a particular color region is consistent with the color measurements of the adjacent color regions. If, for example, a color / optical measurement for a region indicates a darker region when compared to an adjacent region, but the frozen image indicates that the inverse should be true, then computer 384 could notify the dentist (as with an audio tone) that one or more regions should be re-measured with the intraoral reflectometer 380. The computer 384 could make such relative color determinations (although the color values stored in the 384 computer of the frozen frame process are not true the color values) because the variations from region to region must follow the same pattern as the color / optical measurements taken by means of the intraoral reflectometer 380. Thus, if a region is darker than its neighbors, then the computer 384 will expect that the color measurement results from the 380 intraoral reflectometer for the region will also be more obscure with respect to the results and color measurement for neighboring regions, etc.
As with the results of color measurement and captured images previously discussed, the frozen image of the tooth, together with the results of color / optics measurement for various regions of the tooth, could be conveniently stored, maintained and entered as part of the patient's records . Such stored results could be used advantageously in the creation of dental prostheses that more correctly match the adjacent colors / regions of the tooth.
In an additional refinement of previous mode, the compiler 384 preferably includes here, or coupled thereto, a modem. With such modem capacity
(which could be accessories or program), the computer 384 could couple the results to the remote computer 386 via the telecommunication channel 388. For example, the remote 386 computer could be located in a remotely located dental laboratory. Video images captured using the 382 intraoral camera and the color / optical results collected using the intraoral reflectometer could be transmitted to a dental technician (for example) at the remote location, who could use such an image and results to build a dental prosthesis. Additionally, computer 384 and remote computer 386 could be equipped with an internal or external video teleconferencing capability, thus allowing a dentist and a dental technician or ceramist, etc., to have a live video or audio teleconference while see such images and / or results.
For example, a live teleconference could be performed, so the dental technician or ceramist observes the video images captured using the intraoral camera 383, and after observing the images of the patient's tooth and facial characteristics and complexion, etc., instructs the dentist as to which areas of the patient's teeth it is recommended to measure using the intraoral 380 reflectometer. Such interaction between the dentist and the dental technician or ceramist could be presented with or without freezing as previously described. Such interaction could be especially desirable in, for example, a probe phase of a dental prosthesis, when minor changes or subtle characterizations might be needed to modify the prosthesis for optimal esthetic results.
Even in an additional refinement it could be understood with reference to FIG. 26. As illustrated in FIG. 26, the color calibration chart 404 could be used in combination with several elements of the previously described modes, including the intraoral camera 382. The color calibration chart 404 could provide a chart of known color values, which could be used, by example, in the video image to further improve the correct skin tones of patient 402 in the displayed video image. Since the patient's gingival tissue, complexion and facial features, etc., could influence the final aesthetic results of the dental prosthesis, such a color calibration chart might be desirable to use to provide better aesthetic results.
As a further example, such color calibration chart could be used by computer 384 and / or 386 to "calibrate" the color results within a captured image to know or know the color values. For example, color calibration chart 404 could include one or more orientation marks 406, which could allow computers 384 and / or 386 to find a position on color calibration chart 404 within the video frame. Subsequently, computers 384 and / or 386 could then compare values of "known" color results from the color calibration chart (the results indicative of the colors within the 404 color calibration chart and their position relative to the mark or orientation marks 406 are stored within computers 384 and / or 386, such as in the search table, etc.) with the colors captured within that of the video image in the positions corresponding to the different colors of the color calibration chart 404. Based on such comparisons, the computer 384 and / or 386 could adjust the color to the video image to effect a more serried correspondence between the colors of the video image or and the true or known colors of the color calibration chart 404.
In certain embodiments, such color adjustment video results could be used in the prosthesis preparation process, such as to adjust the color of the video image (whether or not it is frozen) in conjunction with the collected color / optical results. using the intraoral reflectometer 380 (eg, as described above or using the results of the intraoral reflectometer 380 to further adjust the color portions of the video image), or to add subtle characterizations or modifications to a dental prosthesis or to prepare yet a dental prosthesis, etc. As long as it is not believed to be accurate, etc. As the color / optical results collected using the 380 intraoral reflectometer, such color adjustment video results could be suitable in certain applications, environments, situations, etc., and such color adjustment video results could be used from a similar to the color results taken by means of a device such as the intraoral reflectometer 380, which includes, for example, the preparation of prosthesis, collection and storage of the patient's results, preparation of materials, as described in another part here.
It should also be noted that the 404 color calibration chart could be specifically adapted (size, shape and constituent materials, etc.) to be positioned inside the patient's mouth to be placed close to the tooth or teeth to be examined, to be subjected to the same or almost the same environmental lighting and environmental conditions, etc., as is the tooth or teeth to be examined. It should also be noted further that the use of color calibration chart 404 for the results of the correct color video image with a computer as provided herein could also be adapted for use in other fields, such as medical, industrial, etc. , although its new and advantageous use in the field of dentistry as described here is one of observation and particular emphasis.
FIG. 27 illustrates a further embodiment of the present invention in which an intraoral reflectometer according to the present invention could be adapted to be mounted on, or removably fixed to, a dental chair. An exemplary dental chair arrangement in accordance with the present invention includes the dental chair 410 which is mounted on the base 412 and could include typical accessories for such chairs, such as control foot 414, hose (s) 416 (for suction or water , etc.) Tarja and water supply 420 and light 418. A preferably movable arm 422 extends outwardly of support 428 to provide a conveniently located support 430 in which various dental instruments 424 are removably mounted or fixed. Tray 426 could also be included, in which a dentist could place other instruments or materials. According to this embodiment, however, the instruments 424 include an intraoral reflectometer according to the present invention, which is conveniently positioned and removably mounted / fixed to the holder 430, so that color / optical measurements, collection and Storage of results and preparation of prostheses can be carried out conveniently by the dentist. Opposed to the large and bulky prior art instruments, the present invention allows an intraoral reflectometer for collection of color / optical results, in some embodiments combined or used with an intraoral camera as described elsewhere herein, which could be adapted easily to be placed in a convenient place on a dental chair. Such a dental chair could also be easily adapted to maintain other instruments, such as intraoral cameras, drills, lights, etc.
AdiGionally, and to emphasize the wide utility and variability of several of the inventive concepts and techniques set forth herein, it should be apparent to those skilled in the art from the point of view of the foregoing that apparatus and methodology could be used to measure the properties optical objects / teeth using other focusing and optical joining elements, in addition to the optical fibers employed in the preferred embodiments herein. For example, lenses or mirrors or other optical elements could also be used to construct the light source element and the light receiving element. A flash light or other commonly available light source, as particular examples, could be used as the light source element, and a common telescope with a photoreceptor could be used as the receiving element in a larger scale embodiment of the invention. Such refinements using the indications provided herein are expressly within the scope of the present invention.
As will be apparent to those skilled in the art, certain refinements could be made in accordance with the present invention. For example, an optical fiber of the central light source is used in certain preferred embodiments, but other light source arrays (such as a plurality of light source fibers, etc.). In addition, the search tables are used for various aspects of the present invention, but calculations of the polynomial type could be used similarly. Thus, while several preferred embodiments of the present invention have been set forth for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and / or substitutions are possible without departing from the scope and spirit of the present invention as set forth in the claims. .
The reference is also made to the compendium of the international application filed on the same date with it according to the Patent Cooperation Treaty, for "Apparatus and Method of Measurement of Optical Characteristics of an Object", by the inventors thereof, which is incorporated herein by reference.
It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it refers.
Having described the invention as above, the content of the following is claimed as property.
Claims (81)
1. A method for producing a dental prosthesis for a patient, characterized in that it comprises the steps of: measuring a tooth of the patient, the measurement step comprises moving a probe in proximity to the tooth, wherein the probe provides light to the surface of the tooth from one or more light sources, and receives light reflected from the tooth by means of a plurality of light receptors, which determine the intensity of the reflected light received by more than one of the light receivers with the first detectors, and which measure the optical characteristics of the tooth with the second detectors based on the light received by one or more of the light receptors in response to the intensity determinations made by the first detectors, where the measurement produces results indicative of the optical characteristics of the tooth; generate results of the dental prosthesis based on the measurement results; Y Prepare the dental prosthesis based on the results generated.
2. The method of claim 1, characterized in that the step of generating results for the dental prosthesis comprises generating results that determine an equalization between the measured results and a dental shadow guide.
3. The method of claim 1, characterized in that the optical characteristics of the tooth comprise color characteristics.
4. The method of claim 1, characterized in that the optical characteristics of the tooth comprise transparency characteristics.
5. The method of claim 1, characterized in that the optical characteristics of the tooth comprise fluorescence characteristics.
6. The method of claim 1, characterized in that the optical characteristics of the tooth comprise surface texture characteristics.
7. The method of claim 1, characterized in that the probe comprises one or more optical fibers of the light source coupled to a light source and a plurality of light receiving optical fibers coupled to the first and second detectors.
8. The method of claim 1, characterized in that the plurality of light receptors are each spaced a first distance from a first light source in the probe, and wherein the plurality of light receivers are spaced from the adjacent light receptors in the probe for a second distance.
9. The method of claim 8, characterized in that the probe comprises three light receptors spaced around the first light source, wherein the light receptors are spaced from the adjacent light receptors with a spacing angle of about 120 degrees.
10. The method of claim 1, characterized in that the first detectors comprise light measuring detectors measuring the same wide band, and wherein the second detectors comprise a color spectrophotometer.
11. The method of claim 10, characterized in that the second detectors comprise a plurality of filters optically coupled to a plurality of light measuring devices.
12. The method of claim 11, characterized in that the filters comprise filters that pass light below a predetermined frequency of received light.
13. The method of claim 1, characterized in that the first detectors comprise light measuring detectors measuring the same wide band, and wherein the second detectors comprise a color measuring device of triple stimulus type values.
14. The method of claim 1, characterized in that it also comprises the steps of: process the results' measured with a computing device; Y display a representation that corresponds to the results measured in an exhibition device.
15. The method of claim 14, characterized in that the counting device is coupled to a telecommunication device, the method further comprising the transmission of results corresponding to the measured results to a remote installation, wherein the step of preparing the dental prosthesis is performs at least in part on the remote installation.
16. The method of claim 15, characterized in that the remote installation comprises a laboratory for preparing dental prostheses, wherein the method further comprises the step of measuring the prepared dental prosthesis.
17. The method of claim 1, characterized in that the step of generating results for the dental prosthesis comprises generating results indicative of the constituent materials of the dental prosthesis.
18. The method of claim 17, characterized in that the step of preparing the dental prosthesis comprises manufacturing the dental prosthesis based on the constituent materials.
19. The method of claim 18, characterized in that the dental prosthesis comprises a colored filling material for the tooth.
20. The method of claim 18, characterized in that the dental prosthesis comprises a dental crown having optical characteristics corresponding to the adjacent tooth.
21. The method of claim 18, characterized in that the dental prosthesis comprises a cement having color content and an element of the dental prosthesis that is semi-transparent.
22. The method of claim 1, characterized in that it further comprises the generation of audio information, wherein the audio information is indicative of the state of the measurement step.
23. The method of claim 1, characterized in that the probe has a removable cover element.
24. The method of claim 23, characterized in that the removable cover element comprises a buckle.
25. The method of claim 23, characterized in that it further comprises positioning the cover element on the probe before measuring the tooth.
26. The method of claim 23, characterized in that it further comprises sterilizing the removable cover element and placing the covered element on the probe before measuring the tooth.
27. The method of claim 1, characterized in that the probe has a removable tip.
28. The method of claim 27, characterized in that it also comprises the placement of the removable tip in the probe before measuring the tooth.
29. The method of claim 27, characterized in that it further comprises the sterilization of the removable tip and placement of the removable tip in the probe before measuring the tooth.
30. The method of claim 1, characterized in that it comprises the step of determining the intensity of reflected light with the first detectors comprising the steps of: determining a first peak intensity value with one or more of the first detectors as the probe moves toward the tooth; and determining a second peak intensity value with one or more of the first detectors as the probe moves away from the tooth.
31. The method of claim 30, characterized in that the tooth is measured with the second detectors when the first and second peak values of intensity are substantially equal.
32. The method of claim 30, characterized in that it also comprises the steps of; compare the first and second peak intensity values; accepting the results measured by the second detectors if the first and second peak intensity values compared are within a predetermined range; Y reject the results measured by the second detectors if the first and second peak intensity values compared are outside the predetermined range.
33. The method of claim 32, characterized in that it also comprises the steps of: generate the first audio information if the measured results are acceptable; Y »Generate the second audio information if the measured results are rejected.
34. The method of claim 32, characterized in that it further comprises the step of modifying the predetermined range.
35. The method of claim 30, characterized in that it further comprises the step of determining an intermediate intensity value with the first detectors at an intermediate time between the time when the first and second peak intensity values are determined, wherein the intermediate intensity value correspond to the transparency of the tooth.
36. The method of claim 35, characterized in that the intermediate intensity value is determined when the probe is in contact or almost in contact with the tooth.
37. The method of claim 1, characterized in that the optical characteristics of the tooth are measured without the probe making contact with the tooth.
38. The method of claim 1, characterized in that the tooth is measured at a time when a plurality of the first detectors measure peak intensity values as the probe moves with respect to the tooth.
39. The method of claim 1, characterized in that the tooth is measured when the probe is at a predetermined distance from the tooth.
40. The method of claim 1, characterized in that the tooth is measured when the probe is at a predetermined distance and angle with respect to the tooth.
41. A method for determining the optical characteristics of a tooth, characterized in that it comprises the steps of: measuring the tooth by moving a probe in proximity to the tooth, wherein the probe provides light to the tooth surface of one or more light sources, and receives light reflected from the tooth by means of a plurality of light receptors; determine the intensity of reflected light received by more than one of the light receivers with the first detectors; Y measuring the optical characteristics of the tooth with the second detectors based on the light received by one or more of the light receptors in response to the intensity determinations made by the first detectors, where the measurement produces results indicative of the optical characteristics of the tooth .
42. The method of claim 41, characterized in that the optical characteristics of the tooth comprise color characteristics.
43. The method of claim 41, characterized in that the optical characteristics of the tooth comprise transparency characteristics.
44. The method of claim 41, characterized in that the optical characteristics of the tooth comprise fluorescence characteristics.
45. The method of claim 41, characterized in that the optical characteristics of the tooth comprise surface texture characteristics.
46. The method of claim 41, characterized in that the probe comprises one or more optical fibers of the light source coupled to a light source and a plurality of light receiving optical fibers coupled to the first and second detectors.
47. The method of claim 41, characterized in that the plurality of light receivers are each spaced a first distance from a first light source in the probe, and wherein the plurality of light receivers are spaced from the light receptors adjacent to the probe by means of a second distance.
48. The method of claim 47, characterized in that the probe comprises three light receptors spaced around the first light source, wherein the light receivers are spaced from the adjacent light receptors with an angular space of approximately 120 degrees.
49. The method of claim 41, characterized in that the first detectors comprise the light measuring detectors measuring the same wide band, and wherein the second detectors comprise a color spechotometer.
50. The method of claim 49, characterized in that the second detectors comprise a plurality of filters optically coupled to a plurality of light measuring devices.
51. The method of claim 50, characterized in that the filters comprise filters that pass light below a predetermined frequency of received light.
52. The method of claim 41, characterized in that the first detectors comprise light measuring detectors measuring the same wide band, and wherein the second detectors comprise a color measuring device of triple stimulus type values.
53. The method of claim 41, characterized in that it also comprises the steps of: process the measured results with a computing device; Y Display a representation that corresponds to the results measured on a display device.
54. The method of claim 53, characterized in that the computing device is coupled to a telecommunication device, the method further comprising the transmission of results corresponding to the results measured in a remote installation.
55. The method of claim 41, characterized in that the method further comprises generating audio information, wherein the audio information is indicative of the state of the determination of the optical characteristics.
56. The method of claim 41, characterized in that the probe has a removable cover element.
57. The method of claim 56, characterized in that the removable cover element comprises a buckle.
58. The method of claim 56, characterized in that it also comprises the placement of the removable cover element in the probe before measuring the tooth.
59. The method of claim 56, characterized in that it further comprises the steps of sterilizing the removable cover element and placing the cover element on the probe before measuring the tooth.
60. The method of claim 41, characterized in that the probe has a removable tip.
61. The method of claim 60, characterized in that it also comprises the placement of the removable tip in the probe before measuring the tooth.
62. The method of claim 60, characterized in that it further comprises sterilizing the removable tip and placing the removable tip on the probe before measuring the tooth.
63. The method of claim 41, characterized in that the step of determining the intensity of light reflected with the first detectors comprises the steps of: determining a first peak intensity value with one or more of the first detectors as the probe moves toward the tooth; and determining a second peak intensity value with one or more of the first detectors as the probe moves away from the tooth.
64. The method of claim 63, characterized in that the tooth is measured with the second detectors when the first and second peak values of intensity are substantially equal.
65. The method of claim 63, characterized in that it further comprises the steps of; compare the first and second peak intensity values; accepting the results measured by the second detectors if the first and second peak intensity values compared are within a predetermined range; Y reject the results measured by the second detectors if the first and second peak intensity values compared are outside the predetermined range.
66. The method of claim 65, characterized in that it further comprises the steps of; generate the first audio information if the measured results are acceptable; Y generate the second audio information if the measured results are rejected.
67. The method of claim 65, characterized in that it further comprises the step of modifying the predetermined range.
68. The method of claim 63, characterized in that it further comprises the step of determining an intermediate intensity value with the first detectors at an intermediate time between the time when the first and second peak intensity values are determined, wherein the intermediate intensity value corresponds to the transparency of the tooth.
69. The method of claim 68, characterized in that the intermediate intensity value is determined when the probe is in contact or almost in contact with the tooth.
70. The method of claim 41, characterized in that the optical characteristics of the tooth are measured without the probe making contact with the tooth.
71. The method of claim 41, characterized in that the tooth is measured in time when a plurality of the first detectors measure peak peak intensity values as the probe moves with respect to the tooth.
72. The method of claim 74, characterized in that the tooth is measured when the probe is at a predetermined distance from the tooth.
73. The method of claim 41, characterized in that the tooth is measured when the probe is at a predetermined distance and angle with respect to the tooth.
74. The method of claim 41, characterized in that it also comprises the steps of: store a record of patient results in a computer system; provide the measured results to the computer system; and update the patient's results record with the measured results.
75. The method of claim 74, characterized in that it also comprises the steps of: measuring a plurality of teeth of the patient; providing the measured results of the plurality of teeth to the computer system; Y update the record of patient results with the measured results of the plurality of teeth.
76. The method of claim 74, characterized in that it further comprises the steps of; prepare the image results corresponding to the tooth with an intraoral camera; provide the image results to the computer system; Y update the patient's results record with the image results.
77. The method of claim 75, characterized in that it further comprises the steps of; preparing the image results corresponding to the plurality of teeth with an intraoral camera; provide the image results to the computer system; Y update the patient's results record with the image results.
78. The method of claim 74, characterized in that the tooth is divided into a plurality of sectors, wherein the measurements of the optical characteristics of the tooth are made in the plurality of sectors, wherein the measured results of the plurality of sectors are stored in the record of patient results.
79. The method of claim 41, characterized in that it further comprises the step of placing a device positioned on the tooth before measuring the tooth, wherein the placement of the positions of the device are relative to the placement of the probe with respect to the tooth.
80. The method of claim 41, characterized in that the probe is adapted to be mounted on the dental chair in which a patient whose tooth is to be measured is positioned, where the probe is removable from the dental chair and can be placed close to the tooth for the measurement of the tooth.
81. An apparatus for measuring the color of a tooth with a probe as the probe moves with respect to the tooth, characterized in that it comprises: a probe having a central light source and a plurality of light receptors spaced from the central light source, wherein the light from the central light source is reflected in the plurality of light receptors; detectors coupled to receive light from the light receivers, wherein at least some of the detectors measure the value of the intensity of the light in predetermined color bands; a processor coupled to receive results of the light detectors; wherein the processor monitors the intensity values of one or more of the light receivers and stores the results of the detectors in time when one or more light receivers have a peak intensity value.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US08582054 | 1996-01-02 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| MXPA98005172A true MXPA98005172A (en) | 1999-06-01 |
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