the Beer's law applies only to dilute solution.
1.1.3.6 Stray light, stray light is wavelength component which is not
required, but enters the detector and is outside the tested
spectral bandwidth range. It comes mainly from the
spectrometer dispersion element prism or a grating, mirrors,
scattering of lens surface, monochrome dust of inner wall
and reflection and diffuse of other elements scars, etc.
Stray light can cause serious measurement errors. When
the instrument energy is at the minimum wavelength, stray
light is usually at its maximum (e.g. deuterium lamp 220nm,
tungsten lamp 340nm).
1.1.3.7 Slit width, slit width not only affects the purity of the
spectrum, but also the absorbance values. In quantitative
analysis, in order to obtain sufficient measurement signal,
should use a larger slit, in the qualitative analysis a small
slit is used, when the exit slit width is equal to the width of
the entrance slit, error caused by slit width is minimal.
1.1.3.8 Wavelength gauge error, wavelength gauge is the
wavelength accuracy of the instrument, if the error is
considerably large or no error correction, the spectral
measurement will cause errors that affect the accuracy of
absorbance measurements (in the peak of absorption
spectrum is more significant).
1.1.3.9 The impact of non-parallel incident light, one of the
prerequisites in Beer's law is the use of a parallel incident
beam, to ensure that all the beam passing through the
same thickness of the absorbing medium, when incident
beam has large deviation from parallel light, obviously
lead to deviations from Beer law. If deviation of parallel
beam is in the instrument moderate, absorbance
measurement error is generally within 0.5%.
1.1.3.10 Luminosity scale error, the accuracy of transmittance, the
error size directly affects the accuracy of photometric
measurements.
