THE AUTOPOL I is Rudolph's most economical automatic polarimeter designed for education and less demanding applications where the budget is critical, but quality is still important. It is available from A.L.P.E .
Rudolph manufactures its least expensive polarimeter with the same high quality optics as its more expensive instruments. While other manufacturers in this price range use Polaroid Plastic Dichroic Sheet Polarisers, Rudolph does not. Instead, Rudolph uses the same high quality Glan Thompson Calcite Polarisers used in its high accuracy models.
High quality polarising prisms are important because polarising prisms are the most critical optical components in the polarimeter. Polaroid prisms are made of a polymeric plastic where the molecules are stretched and oriented in a specific direction so as to linearly polarise light.
These types of plastic sheet polarisers are inexpensive and are vulnerable to heat, warp over time, deteriorate from moisture, and also have greater light absorption than Calcite Polarisers.
In many cases, the plastic polarisers must be replaced in 3 - 5 years. Glan Thompson Calcite Polarisers are comprised of a carbon crystalline structure similar to diamond and have excellent light transmission characteristics. Rudolph guarantees its prisms over the life of the polarimeter.