Abstract

An analog computer for the color evaluation of spectral data is described; ac is used because multiwinding transformers allow isolation of circuits as well as the representation of standard weighting factors by turns-ratios.

The spectrum is fed into the computer by applying suitable voltages to the primaries of 39 “coefficient transformers,” each with three secondary windings. The secondary voltages, summated by series connection, are compared by a null method. The chromaticity coordinates of the test spectrum are thereby rapidly obtained. The computer is relatively inexpensive, easy to operate, and the results are of reasonable accuracy.

© 1964 Optical Society of America

Computation of the Total Illuminance (Encircled Energy) of an Optical System from the Design Data for Rotationally Symmetric Aberrations

Richard Barakat and Marie V. Morello
J. Opt. Soc. Am. 54(2) 235-240 (1964)

Spectral Distribution of Typical Daylight as a Function of Correlated Color Temperature

Deane B. Judd, David L. MacAdam, Günter Wyszecki, H. W. Budde, H. R. Condit, S. T. Henderson, and J. L. Simonds
J. Opt. Soc. Am. 54(8) 1031-1040 (1964)

Calibration of the Donaldson Colorimeter

G. Wyszecki and Y. Nayatani
J. Opt. Soc. Am. 54(5) 705-709 (1964)

Spectral Energy Distribution of Daylight*

H. R. Condit and F. Grum
J. Opt. Soc. Am. 54(7) 937-944 (1964)

Effect of Field Size and Position on Mesopic Spectral Sensitivity

Jo Ann S. Kinney
J. Opt. Soc. Am. 54(5) 671-677 (1964)