Optical properties of lens(4)

(Four) the impact of

Impact resistance is one of the necessary requirements of the Cheap Ray Ban Sunglasses lens material mechanical properties. Test method for impact resistance of commonly used by the United States Food and Drug Administration (FDA) provides a falling ball test to say. The specific method of falling ball test: the use of a 16 g ball from a height of 1.27 meters, at the center of the lens to fall, if the lens is not damaged, the impact resistance performance is good; otherwise the impact resistance performance is poor.

(Five) resistant to breaking point

One of the resistance to breaking point and lens materials required mechanical properties.

Resistance to breaking point test method adopted by the European Standardization Committee formulated the "CEN static deformation test" method. The specific method is: the test at a constant speed, the lens to be measured and gradually increase the pressure, until it reaches the 100 Newton, if the lens is not damaged, its resistance to breaking point performance is good; if the material deformation over 4.5mm, its resistance to breaking point performance deviation; if the lens is corrupted, then the poor performance of resistance to breaking point.

Five, thermal properties

Thermal properties of refers to a change in state of lens material under the influence of heat. The thermal properties include thermal conductivity, specific heat capacity, coefficient of linear expansion, melting point, boiling point, Ray Ban Sunglasses lens of stress temperature.

Six, electrical properties

Electrical properties characteristic of electromagnetic wave and the effect of electric material, sometimes need to lens optical and electrical properties linked to consider. Usually the lens material needs to consider the following two parameters at the time of manufacture, dielectric loss factor and dielectric strength under a predetermined frequency.

Seven, chemical properties

Chemical property refers to the manufacturing Ray Bans Outlet lenses and lens material for daily use, reflecting the characteristic of chemical substances, or is reflected in the characteristics of lens material in some extreme conditions. For example, the accelerated aging experiment for reliability test material, usually use cold water, hot water, acid and various organic solvent test.