Specular Reflectance is a technique for analyzing
transparent films which usually yield weak spectra by
ordinary transmission techniques. Applications include
surface coatings on reflecting substrates; film thickness
measurements by interference fringes and reflectivity
coefficient determinations of metals. The application is
the determining factor when deciding which angle of
incidence should be selected. A 30 degree angle of
incidence is normally chosen for more routine samples which
have coating thicknesses in the micrometer range. For very
thin coatings in the nanometer thickness range, an 80 degree
angle of incidence would be appropriate. When sample
thickness is unknown, the full range of specular reflectance
analysis can be performed conveniently with the VeeMax II,
Variable Angle 30 - 85 degree accessory. Simply move the
sliding lever on the graduated scale to the desired angle.
Using the precision angle adjustment, the angle of incidence
can be increased or decreased depending upon the
sensitivity requirements of the sample. As the angle of
incidence changes the depth of penetration and absorbance
intensity....the angle is selected to optimize sensitivity.
Measured absorbance is directly related to the depth of
penetration controlled by the angle of incidence.
Sensitivity can be further enhanced with the use of a wire
The VeeMax II is also available as an automated accessory. The
automated version offers high performance and conveniently
selects incidence angles that are programmed independently
or simultaneously. Software is integrated to control motion
and data acquisition.
The order details provide for the VeeMax II, Variable Angle
30 - 85 degree Specular Reflectance accessory only. The 30
degree, 80 degree and automated Specular accessories remain
as options and can be ordered separately.