Dynamica HALO DB-20, Инструкция по эксплуатации

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2-3
DB-20 is a double beam system, which features a half mirror to split the beam to
reference beam and sample beam.
The white light emitted from the light source is fed to the Seya-Namioka
monochromator utilizing a concave diffraction grating (with a grating constant
of 1/600 mm, a blaze wavelength of 250nm and a grating area of 20mm ×
25mm), where it is transformed into a monochromatic beam. The beam sent
from the monochromator is reflected by the toroidal mirror (M2), and then
separated into reference beam and sample beam by the half mirror (HM).
The two beams have passed through the sample compartment are focused by
lenses, and are then irradiated into the detector (D1 and D2) where they are
converted into electric signals.
Listed below are the features of this optical system.
The Seya-Namioka optical system utilizing Dynamica’s reputable concave
diffraction grating realizes a monochromator featuring high-energy efficiency
and low stray light level.
The beam is separated by using a half mirror rather than a rotary mirror like in
the conventional double beam spectrophotometer. This structure serves to
eliminate the moving parts, thus realizing a highly stable and reliable
monochromator.
The optical systems on the sample and reference beam sides are absolutely the
same to enable acquiring highly stable data.
2.2.2 Signal Processing and Control System
The electric signal converted from optical signal enters the LOG amplifier
where it is LOG converted to provide absorbance data.
This data is amplified, and is then A/D converted to be processed as digital
value.
The processed results are displayed on the LCD and recorded onto the printer.
2.3 Proper Use of Spectrophotometer
2.3.1 Solvent Selection
When selecting a solvent for sample preparation, keep the following
requirements in mind.
Small absorption in the spectral region of measurement wavelength.
Non – interactive with solute.