Rgb Lasersysteme QWAVE UV Lux-Meter, illumination measuring device, Brightness meter, DSA491006 Datenbogen
Produktcode
DSA491006
Qwave User Manual
14
If the device has been used for a long time or if you need a very precise measurement,
you can easily recalibrate the spectrometer within Waves, if you have a suitable light
source. Recalibration may also be required if the device temperature is outside of the
calibrated temperature range. The device temperature is continuously monitored by the
spectrometer and a warning is displayed, if the temperature has changed considerably.
you can easily recalibrate the spectrometer within Waves, if you have a suitable light
source. Recalibration may also be required if the device temperature is outside of the
calibrated temperature range. The device temperature is continuously monitored by the
spectrometer and a warning is displayed, if the temperature has changed considerably.
After you have recalibrated the spectrometer, you can always restore the factory
calibration in the “Device Properties” window from the File menu.
calibration in the “Device Properties” window from the File menu.
Calibration Accuracy
The wavelength calibration is very accurate and changes only little with time or
temperature. Therefore, most users won’t ever need to recalibrate the wavelengths.
temperature. Therefore, most users won’t ever need to recalibrate the wavelengths.
The dark spectrum calibration also hardly changes. However, if you’re in doubt, you can
always easily recalibrate it because no calibration light source is required.
always easily recalibrate it because no calibration light source is required.
On the other hand, the calibration for the spectral sensitivity depends a lot on your
optical fiber, your measurement probe and how the light is coupled into the
spectrometer. During production of the Qwave spectrometer, we don’t know what your
optical setup is going to be. Therefore the factory calibration for the spectral sensitivity
and especially the absolute intensity is not to be considered as a precise measurement,
but rather as a first estimate. If you require precise intensity measurements, you’ll have to
recalibrate the sensitivity of the whole system including fiber and probe.
optical fiber, your measurement probe and how the light is coupled into the
spectrometer. During production of the Qwave spectrometer, we don’t know what your
optical setup is going to be. Therefore the factory calibration for the spectral sensitivity
and especially the absolute intensity is not to be considered as a precise measurement,
but rather as a first estimate. If you require precise intensity measurements, you’ll have to
recalibrate the sensitivity of the whole system including fiber and probe.
In addition, please note that after changing the exposure time, it takes a few spectra
before the CCD sensor inside the spectrometer reaches its new equilibrium. This means
that after changing the exposure time, the intensities of the following 5 to 10 spectra
may not be as accurate as later measurements. Therefore, for precise measurements we
recommend not to use the auto-exposure feature and to set a fixed exposure time
instead.
before the CCD sensor inside the spectrometer reaches its new equilibrium. This means
that after changing the exposure time, the intensities of the following 5 to 10 spectra
may not be as accurate as later measurements. Therefore, for precise measurements we
recommend not to use the auto-exposure feature and to set a fixed exposure time
instead.
Wavelengths
The mapping of the individual pixels of the spectrum to wavelengths is done using a
third-order polynomial. The four parameters for this function are measured during
manufacturing and stored in the device. Usually, this wavelength calibration does not
change. Therefore, in most cases you don’t need to recalibrate the wavelengths.
However, if the ambient temperature has changed substantially, if the device has been
used for a very long time or if you just would like to make sure that the wavelengths are
really correct, you can recalibrate the wavelength if you have a suitable light source with
several sharp atomic emission lines. These wavelength calibration sources are usually
low-pressure gas discharge lamps filled with Krypton, Neon, Mercury, Argon or Xenon
gas.
third-order polynomial. The four parameters for this function are measured during
manufacturing and stored in the device. Usually, this wavelength calibration does not
change. Therefore, in most cases you don’t need to recalibrate the wavelengths.
However, if the ambient temperature has changed substantially, if the device has been
used for a very long time or if you just would like to make sure that the wavelengths are
really correct, you can recalibrate the wavelength if you have a suitable light source with
several sharp atomic emission lines. These wavelength calibration sources are usually
low-pressure gas discharge lamps filled with Krypton, Neon, Mercury, Argon or Xenon
gas.
To recalibrate, take a spectrum of this light source first. Make sure that the relevant peaks
are automatically detected. If not, adjust the “Peak Finder Parameters” in the Tools Menu.
Then choose “Calibrate Wavelengths” from the Tools menu. In the “Reference Spectrum”
are automatically detected. If not, adjust the “Peak Finder Parameters” in the Tools Menu.
Then choose “Calibrate Wavelengths” from the Tools menu. In the “Reference Spectrum”