A visual colorimeter was designed to implement a new model for the det
ermination of color-matching functions developed in the Munsell Color
Science Laboratory. An instrument utilizing laser primaries was origin
ally developed. The instrument was later improved to incorporate CRT p
rimaries and seven interference filters to make matches to simulated d
aylight in a 2-degrees bipartite field. The system was designed to min
imize the strain on observers. Color-matching functions of naive obser
vers can be measured in approximately 30 minutes. Results from an indi
vidual observer correlate well with data collected on the National Res
earch Council of Canada's Trichromator. Part II of this article gives
the color-matching functions results for 18 observers and 20 repetitio
ns by a single observer.