Jadak PHOTO RESEARCH SpectraScan PR-655, Руководство пользователя

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PR-655/670 User Manual
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FIGURE 48 – PR-655 / PR-670 SPECTROMETER
The uncorrected or ‘raw’ spectrum is corrected using factors established during the factory calibration of the
instrument. These factors include wavelength accuracy correction, spectral distribution correction and
photometric correction. The wavelength calibration is performed using a helium spectral line source. The line
source provides known spectral emission lines that the software uses to map the dispersion of the grating to the
multi-element detector. The helium lines used during the wavelength calibration are 388.6 nm, 447.1 nm, 471.3
nm, 587.6 nm, 667.8 nm, 706.5 nm and 728.13 nm.
Next, the data is corrected by spectral factors. These factors insure that the spectral power distribution (SPD) of
the target is and calculated values such as CIE Chromaticity are accurately reported. Lastly, a scaling factor
(photometric factor) is applied ensuring the proper photometric levels such as luminance or illuminance are
displayed.
Calculations
The corrected spectral data is then used to calculate photometric and colorimetric values including luminance,
CIE 1931 x, y and 1976 u’, v’ chromaticity coordinates, correlated color temperature and dominant. Following
are some of the basic calculations used to generate photometric and colorimetric parameters:
256-detector
array
Diffracted
light
Diffraction
grating
Objective
lens
Aperture
mirror
Optical
radiation
Eyepiece
Input Slit
Grating
Incident
light