Abstract:
An instrument and related process for measuring color, shade, gloss, shape and/or translucence of a tooth. First, the instrument uses searchlight illumination to illuminate a tooth with constant irradiance. Second, the instrument uses calorimetric imaging to collect time-separated frames of different wavelengths of light reflected from a tooth and to combine those frames into a color image. Third, the instrument includes a sanitary shield to establish a reference color and a predetermined distance to a target tooth. Fourth, the instrument provides line-of-sight viewing so an operator may simultaneously view a display of the image on the instrument and the object being measured. Fifth, the instrument is impervious to pollutants because it incorporates a sealed measurement window. Sixth, optical measurements of a tooth taken by a dentist are compared to optical measurements of a prosthetic restoration for that tooth to confirm satisfactory matching of optical characteristics of the tooth and restoration.
Abstract:
A color measurement instrument includes a housing and illuminators, a two-dimensional photodetector array, and an optics system within the housing. A UV filter wheel closes the housing to prevent contaminants from entering the housing. The filter wheel supports UV filters and non-UV glass that can be selectively aligned with the illuminators. The photodetectors can be read in parallel, and each photodetector includes a unique spectral filter The optics system delivers light from the sample target area equally to each of the photodetectors.
Abstract:
A color measuring system includes a portable spectrophotometer connectable to a general-purpose computer. The portable unit includes a microprocessor with a read-only program memory storing machine executable instructions to implement data processing for color measurement purposes and input/output functions including key reading and data transfer functions and display functions. A random-access data memory is used to temporarily store process data for later transfer to the general-purpose computer. An editor program and a compiler program in the general-purpose computer may be used to generate a program for the microprocessor using high-level, generalized commands. After such a program has been written and compiled in the general-purpose computer, it is transferred to a command buffer area in the random-access data memory of the microprocessor. The microprocessor, in its program memory, includes a command interpreter including a predefined sequence of machine executable instructions for each generalized command. When executed, the command interpreter reads a generalized command from the data memory and, if necessary, updates relevant data pointers and executes the predefined sequence of machine executable functions in the program memory corresponding to the generalized command being processed. A user, using the general-purpose computer, may specify any desired sequence of measurement operations by specifying functions to be performed by the microprocessor, including the display of prompts to the operator of the portable spectrophotometer to instruct the operator to perform various specified operations.
Abstract:
A method for measuring a like-color region of an object. The method includes defining a first region of a colorimetric image of the object, determining a statistical representation of the first region based on a color metric, and defining a second region of the colorimetric image such that the second region comprises at least a portion of the first region.
Abstract:
An instrument and related process for measuring color, shade, gloss, shape and/or translucence of a tooth. First, the instrument uses searchlight illumination to illuminate a tooth with constant irradiance. Second, the instrument uses colorimetric imaging to collect time-separated frames of different wavelengths of light reflected from a tooth and to combine those frames into a color image. Third, the instrument includes a sanitary shield to establish a reference color and a predetermined distance to a target tooth. Fourth, the instrument provides line-of-sight viewing so an operator may simultaneously view a display of the image on the instrument and the object being measured. Fifth, the instrument is impervious to pollutants because it incorporates a sealed measurement window. Sixth, optical measurements of a tooth taken by a dentist are compared to optical measurements of a prosthetic restoration for that tooth to confirm satisfactory matching of optical characteristics of the tooth and restoration.
Abstract:
A color measurement instrument includes a housing and illuminators, a two-dimensional photodetector array, and an optics system within the housing. A UV filter wheel closes the housing to prevent contaminants from entering the housing. The filter wheel supports UV filters and non-UV glass that can be selectively aligned with the illuminators. The photodetectors can be read in parallel, and each photodetector includes a unique spectral filter. The optics system delivers light from the sample target area equally to each of the photodetectors.
Abstract:
An instrument and related process for measuring color, shade, gloss, shape and/or translucence of a tooth. First, the instrument uses searchlight illumination to illuminate a tooth with constant irradiance. Second, the instrument uses calorimetric imaging to collect time-separated frames of different wavelengths of light reflected from a tooth and to combine those frames into a color image. Third, the instrument includes a sanitary shield to establish a reference color and a predetermined distance to a target tooth. Fourth, the instrument provides line-of-sight viewing so an operator may simultaneously view a display of the image on the instrument and the object being measured. Fifth, the instrument is impervious to pollutants because it incorporates a sealed measurement window. Sixth, optical measurements of a tooth taken by a dentist are compared to optical measurements of a prosthetic restoration for that tooth to confirm satisfactory matching of optical characteristics of the tooth and restoration.
Abstract:
Imaging that uses glare to confirm proper measurement of a sample. An imaging device illuminates an object and generates glare (i.e., specular reflection, diffuse reflection or a combination of the two) off the object's surface, which is displayed on a display as a glare artifact. The location of the glare artifact is compared to a predetermined location to establish adjustment to obtain a desired angular orientation. The imaging device optionally highlights the glare artifact and steers a user to obtain the desired presentation angle. In two other embodiments, the spatial relationship between the imaging device and the object is time-varied. In one, the imaging device monitors changing glare and acquires a measurement when a desired glare is detected. In the other, the imaging device captures multiple images including varying glare artifacts and analyzes the images to select a preferred image having a glare artifact indicative of a desired angular orientation.
Abstract:
A color measuring system (10) includes a portable spectrophotometer (100) connectable to a general-purpose computer (130). The portable unit (100) includes a microprocessor with a read-only program memory for storing machine executable instructions and input/output functions. A random-access data memory is used to temporarily store process data for later transfer to the general-purpose computer (130) or to store in a command buffer area transferred high-level, generalized commands from the general-purpose computer (130). The microprocessor also includes a command interpreter which reads a generalized command from data memory and executes the predefined sequence of machine executable functions.