CS-200 from Konica Minolta is an instrument that enables highly
accurate luminance and chromaticity measurements, comparable to those
of the spectroscopic type of instrument while maintaining the
simplicity, operability, and competitive price of the tristimulus type.
The CS-200 features 40 sensors and performs calculations using the
spectral sensitivity characteristics (colour-matching functions)
corresponding to the sensitivity of human eye. With this newly
developed spectral fitting method, tristimulus values (XYZ for red,
green, and blue) with a far higher accuracy than those of conventional
tristimulus colorimeters can be obtained, providing excellent accuracy.
Measurements over a wide range of luminance levels from a low luminance
of 0.01 cd/m2 through high luminance of 20,000,000cd/m2 (with measuring
angle of 0.1°) can be done.
Three measuring angles can be selected: 1°, 0.2°, and 0.1°.
The measuring angle can be switched according to the measurement
target, ranging from display devices or other objects with large areas
to measure through objects with tiny areas to measure, such as car
audio control panels, vehicle instrument panels, and compact LCDs.
Areas of application
Light sources of all types can be measured with the CS-200, for example
signal, traffic lights, airport lighting, lamps, LEDs, picture tubes,
LCDs, PDPs, etc., simply anything that emits light. With the
ever-growing demand for diversified media stimulated by the growth of
information-technology business and full-scale service of digital
broadcasting, research and development have been accelerated for
various display devices, centering on plasma displays and LCDs.
Innovations in LED technology have led to remarkable breakthroughs in
the development of LED products including traffic lights, backlights
for reflective LCDs, and large outdoor display screens.
There are two ways of determining luminance and chromaticity values for a light source.
A tristimulus type of instrument measures light sources with three
sensors (red, green, blue) that have sensitivity similar to the
sensitivity of human eyes to light. The filters used to reach this
sensitivity have a limit in precision and thus the readings of
tristimulus instruments can not be perfect on all kind of light
sources. Best accuracy is reached when measuring light sources with a
similar spectral distribution like that of the light source used for
calibration of the instrument.
The second method, which is used by the CS-200, is to measure the
spectral emittance of the light source and perform calculations using
the spectral sensitivity characteristics (color-matching functions)
corresponding to the sensitivity of human eye. By this method, the
mis-matching of filters is avoided and thus the measurement results are
much more precise.