What is the benefit of glass lens over a plastic?
There are number of reasons that mineral glass lenses provide exceptional clarity and robustness over that of plastic lenses.
High quality glass mineral lens offers less distortion than plastic as it has a better surface form and refraction index, so allowing more light through providing better optical clarity of the image.
Plastic can be easily scratched and is less durable than glass and can be accidentally melted through contact with a hot source such as solder or splatter as well as being is less resistant to chemical and solvents.
Glass lenses bench magnifiers are usually higher quality than plastic lens versions and are more suited to industrial, scientific and manufacturing applications.