15
6 Click next and cover the sensor or turn off
the calibration source so the dark
reference spectra can be measured
7 Click next
–
and the calibration is then
finished.
When you close the calibration dialog will you be asked if you want to save the
calibration to the device. When selecting yes, the custom calibration will be saved
inside the device you can always switch back to the factory calibration at any time.
Accuracy
The accuracy of the LightSpion device consists of the sum of individual accuracies of
the involving parts as follows:
▪
Photo spectrometer accuracy
▪
Optical sensor accuracy
▪
Circular field accuracy
The accuracies of these devices are described below.
Photo spectrometer accuracy
The spectrometer used in the LightSpion is Ocean Optics STS-VIS.
The accuracy of the spectrometer has been previously tested in a wide temperature
range from -10 to +50 degrees, therefore the device is adjusted for a temperature
drift.
The linearity of the photo spectrometer is corrected to have an error < +/- 0.5% from
15-95% full scale (2,500
–
14,000 counts net).
The effect of the linearity error will also affect the color and CRI measurements so
the complete series of measurement errors are as follows:
▪
Intensity error
< +/- 0.5%
▪
Color temperature error < +/- 35 Kelvin
▪
CRI error
< +/- 0.7%
Optical sensor accuracy
The accuracy of the sensor depends on a change of a sensitivity field as a function of
position (it is also called the sensitivity span). The measurement setup with an
indicated sensitivity span of less than 8.5% is presented below.
