Bellingham and Stanley Abbe 60, Руководство пользователя, Страница: 8 / 26

The upper & lower prism boxes
A liquid sample to be tested is placed on the measurement prism and the upper prism is clamped
down onto it forming a thin layer of the sample. Light from the light source passes through upper
prism, then is refracted through the sample layer and into the measurement prism.
The upper prism box is held in place by a toggle clamp, which also forces the box up by a few
millimetres when opening. The toggle clamp also prevents the upper prism box dropping directly
onto the measurement prism and causing damage to the surface.
The upper & lower prism boxes both incorporate water jackets, each with two hose connection
nozzles. This enables the sample to be temperature controlled from a water circulator.
Measurement prism
Lower prism box
Prism box toggle clamp
Water nozzles
Any deterioration of the surface condition of the measurement prism will limit the performance of
the instrument and make accurate measurements difficult.
It is important to keep the measurement prism in good condition.
The temperature display module
The current temperature of the measurement prism is continually monitored and shown on the
display on the rear face of the instrument in degrees Celsius.
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