The Variable Pathlength Liquid Spectrophotometer Cell can eliminate the need for a large collection of different fixed pathlength cells at an economical price.
The Variable Pathlength Liquid Spectrophotometer Cell consists of a cylindrical stainless steel chamber containing parallel windows. The pathlength may be continuously adjusted from 0.05mm to 5mm and reproduced within 0.001mm (1 micrometer). A vernier scale provided on the cylinder permits the cell pathlength to be read within 0.0005mm (0.5 micrometer).
In order for weaker absorption bands of many liquids to appear with the proper intensity, the stronger bands will be totally absorbed and their exact location thus obscured. In these situations, the Variable Pathlength Cell may be precisely adjusted to provide just the right intensity for exact location of both weak and strong bands.
The Variable Pathlength Liquid Spectrophotometer Cell is useful in both solvent compensation and differential analysis. When filled with solvent and mounted in the reference beam of a dispersive spectrophotometer, its pathlength may be adjusted to compensate for unwanted solvent absorption in the sample beam.
In differential analysis, two liquids are examined that may differ only slightly in the concentration of a minor component. Careful adjustment of the variable cell pathlengths will tend to enhance the spectrum of the minor component contained in a fixed path cell in the sample beam.