PROCEEDINGS ARTICLE | August 21, 2013
Proc. SPIE. 8908, International Symposium on Photoelectronic Detection and Imaging 2013: Imaging Sensors and Applications
KEYWORDS: Sensors, Calibration, Spectroscopy, Reflectivity, Colorimetry, Personal digital assistants, Detector arrays, Spectral resolution, CCD image sensors, Diffraction gratings
A reflectance colorimetry measurement system is constructed using scanning spectrometer with array detector, and the
color measurement can be achieved under 45:0 and 0:45 geometry conditions. Typically, there are two types of
spectrometer for colorimetry measurement: the scanning spectrometer with single-channel detector requires
point-by-point spectral reading, and the measurement is time consuming; array sensor spectrometer (multichannel
spectrometer) can completes the measurement in a few milliseconds, but its spectral resolution and range are limited by
the array sensor and the optical elements. This colorimetry measurement system is designed for color calibration service,
it using a scanning spectrometer with array detector, which divides the board spectral measurement range into sections,
and uses the array detector to measure each section respectively, thus achieving the rapid measurement of spectral data
with high resolution and wide wavelength range, so as to realized fast color measurement with high precision. The array
sensor of the system using a photo diode array (PDA) with 1024 pixel, having a larger dynamic range and better linearity
compared to CCD. The grating is rotated with a precision rotation stage, and the rotation angle is calculated basing the
parameters of grating and collimator lens, so as to stitch the spectral data of each measurement section., the measurement
signal is mutated at the junction point between measurement sections, due to the rotation angle and the shape of grating
efficiency curve. The theoretical analysis and experiment shows that the signal mutation at the junction point can be
eliminated by comparison measurement of reflectance.
