Colorimeter for dental applications

Abstract

The invention is a colorimeter for dental applications comprising a hand-held probe, similar in size to a dental drill, attached by an electrical cable to a small self-contained display module. The calorimeter provides the capability for measuring the colors of a number points along a line on the surface of an object such as a tooth. A measurement is made while placing the tip of the probe against, or in close proximity to, the surface of the object. The display module to which probe attaches contains a microprocessor and provides a control, display and data interface to the operator. The display module can be adapted for fastening to the wrist of the operator thereby leaving both hands free to manipulate the probe and other tools. The calorimeter is particularly well suited for measuring the color of teeth in a dentist's office in preparation for making dental prostheses which accurately match the color of natural teeth. The colorimeter generates from a single measurement an array of color data points measured along a line on the surface of an object. From those data points, the processor can perform statistical analysis yielding a single color value, generate and display a color profile along a surface, compare measured values with a preloaded table of values, or upload color data to a remote location for laboratory or manufacturing purposes. The colorimeter can also use variations in the color values measured along a line to identify boundaries of areas on a surface. For example, the color profile can be used to identify the gum line on a tooth. The probe comprises multiple light emitting diodes (LEDs) for successively emitting light of different colors toward a surface, a linear photosensor array for receiving light reflected from the surface, and a lens for directing light from the target to the array, all contained within the probe itself. The calorimeter may also comprise a cradle for storing the probe and display module when not in use. The cradle may provide a battery charger, calibration references, and data links for uploading or downloading data from a remote location.