Halma Ocean Optics QE65000, Инструкция по установке и эксплуатации

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4: Sample Experiments
Note
If possible, do not turn off the light source when taking a dark spectrum. If you must turn
off your light source to store a dark spectrum, allow enough time for the lamp to warm up
again before continuing your experiment.
You must take a dark spectrum before measuring transmission.
5. Put the sample in place and ensure that the light path is clear. Then, take a reflection
measurement by clicking on the Transmission Mode icon on the toolbar or selecting Spectrum |
Transmission Mode from the menu bar (since the mathematical calculations used to calculate
transmission and reflection are identical). To save the spectrum to disk, click the Save icon on the
toolbar or select File | Save | Processed from the menu bar.
Note
If you change any sampling variable (integration time, averaging, smoothing, angle,
temperature, fiber size, etc.), you must store a new dark and reference spectrum.
Relative Irradiance Experiments
Irradiance is the amount of energy at each wavelength emitted from a radiant sample. In relative terms, it
is a comparison of the fraction of energy the sample emits and the energy the sampling system collects
from a lamp with a blackbody energy distribution (normalized to 1 at the energy maximum). OOIBase32
calculates relative irradiance with the following equation:
S
λ
- D
λ
I
λ
= B
λ
(
R
λ
- D
λ
)
Where:
B
λ
= the relative energy of the reference (calculated from the color temperature) at wavelength
λ
S
λ
= the sample intensity at wavelength
λ
D
λ
= the dark intensity at wavelength
λ
R
λ
= the reference intensity at wavelength
λ
The following figure shows a typical relative irradiance setup. A light source with a known color
temperature (such as the LS-1 or LS-1-LL) is used to take a reference spectrum. The light to measure is
accumulated through a CC-3 Cosine Corrector (or FOIS integrating sphere) into an input fiber, which
carries the light information to the spectrometer. The spectrometer then transmits the information to the
PC, which compares the measured spectra against the reference spectrum, thus removing wavelength-
dependent instrument response from the measurement.
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