Investigation of antistatic properties of spectacle lenses with antireflective coatings

Static electricity arises when two materials in contact are separated after rubbing and the speed of charge movement on surface is slow. Retained electrostatic charge on the surface of materials can create risks and problems in many areas of industry, for example films and light fabrics cling can attract airborne dust or semiconductor devices may be damaged. Therefore electrostatic dissipative and antistatic additives are used in many applications to avoid risks from static electricity. In case of optical lenses antistatic coatings can be used to avoid accumulation of static charge on their surfaces. Quantity of the charge deposited on samples surface and how quickly deposited charge migrated away from the surface was measured using fast response electrostatic fieldmeter. In this work the antistatic properties of optical lenses coated with different antireflective coatings were investigated and their ability to dissipate static electricity was determined. Static dissipation properties were investigated in relation to corona discharge time changes. It has been shown that increasing corona discharge time affected badly on charge decay time of optical lenses.