【Function】You can observe the light and dark stripes of the lens, the force distribution during the injection molding process, and check the changes in installation force and Whether it is crystal lens. 【Brightness Adjustable】This machine can adjust the brightness of the light source by rotating the upper Polarized Turntable. 【How to Use】Place the glasses to be tested between the analyzer and polarizer of the stress meter, observe the stress around the spectacle lenses in the lens ring from top to bottom, determine whether the stress around the spectacle lenses is uniform, and determine Areas that need correction. 【Easy to Use】One-button operation, plug in the power and press the switch to use. Energy saving; easy to use, fast and efficient. 【Application】For all clear lenses and tinted lenses, Suitable for major optical shops, vision care centers, hospitals, optometry training centers, etc.