In Gemmology

Due to the rarity of occurrence, gemstones are very expensive. This is why their identification process of observation and testing is very crucial. This requires huge skill set and a very efficient device. You need more than just naked eyes to determine the flaws in a gemstone. Wherever gemstone is used, its identification becomes extremely important. In gemology, the quality is defined and segregated on the basis of their grades. To categorise them into grades, efficient devices like Polariscopes are used to avoid any financial losses in long run. A layman is absolutely clueless about on what a gemstone is defined as superior or inferior. So, this becomes the moral responsibility of a trader or gemologist to guide him in the best way.

In PET Testing

Polariscope offered by Presto are primarily used for identification of preforms which are used in making PET bottles. Preforms are prone to internal strains and defects, which might result in failure of the final product. These defects appear due to external stress caused by the surroundings. To conveniently make the observations, a preform holder is carved on the observation glass.

What Is a Polariscope and Its Operating Principle?

A polariscope is an optical device that has two Polaroid lenses and an incident light. The three components are arranged in a manner that upper lens also called analyser, then incident light and the polarizer. The analyser has a reeded edge and can be moved into left and right direction. The polarizer is non-movable and completely aligned in line with the analyser.

The incident light is made to pass through the preform sample under test. The PET preform allows the incident to completely pass through it without any refraction. If there is any defect, the light would change its path and refract double. This refraction causes the creation of birefringence phenomenon. According to the pattern formed, the pattern can be matched with the defect chart to analyse the type of defect.

 

 

How to Maintain Your Polariscope?

When not using your Presto bench top model of Polariscope, there are certain measures that are needed to be taken. This definitely helps in increasing the shelf life of the product.

  • Turn off the power of device when not in use.
  • Try avoiding touching the lenses, this causes finger impressions. To wipe off the prints and dust, use a lint free cloth.
  • Always cover the device when not in use.

Try to store in ideal laboratory conditions.