|dc.description.abstract||Techniques of colour measurement and colour reproduction are important in a
wide range of commercial and social activities in most modern economies.
Their study thus constitutes one of the major areas of interest to the CIE.
The project described in this thesis began as an outgrowth of studies of new
types of light sources and of the colorimetry of colour-TV systems; plus a
conviction that modern TV cameras can operate effectively with a wide range of
different illuminating spectra.
It was soon evident that two important prerequisites for this research were: an
understanding of the processes of human colour vision; and a knowledge of the
standard, international, colorimetric terminology of the CIE. These topics are
discussed fully in the text.
Also included is a review of modern gas-discharge lamps, the~y properties, and
their applications. Both high-pressure (HID) types and low-pressure
(fluorescent-tube) types are considered.
Because of the need to measure the colours of surfaces and their TV
reproductions as accurately as possible, various forms of colorimeter were
examined, leading to the choice of a spectrophotometer system for this work.
The design, construction, and evaluation of an original spetrophotometer
system (the UND Spectrophotometer) are described fully in the text.
Finally, attention is given to the operation of a television system under nonstandard
lighting. Twelve different light sources were evaluated as TV ((taking"
illuminants, using both subjective and colorimetric methods of assessment. The
experimental results tend to confirm that colorimetric methods are unsuited to
colour reproduction evaluation, and that subjective methods are more
meaningful. A subjective scale of colour reproduction performance was
established, and it was found to correlate closely with the CIE general colour
rendering index (Ra) for the various test lamps.
The work reported herein predates similar experiments with TV lighting by
other workers, and it includes a wider range of light sources. In spite of
differences in experimental technique, however, there is broad agreement with
their general results.||en