A colorimeter in general is composed of two parts: (1) A device which records the optical data, and (2) a means of interpreting the acquired optical signal. The most basic (and one of the best) colorimeter is the eye-brain combination; however, the results depend on the observer. In 1931 the Commission Internationale de l'Eclairage (CIE) laid down the color matching properties of a standard observer. These properties enable an unbiased classification of an arbitrary spectral distribution and have become the basis of applied colorimetry since 1931. The colorimeter described herein consists of a spectrograph with a solid state array detector for collecting the data and a computer with software for controlling the detector and interpreting the acquired signal using the CIE standard colorimetric observer.