Whether it is an inorganic material or organic material made of optical lenses, in the daily use, due to the friction with the dust or grit (silicon oxide) will cause the lens wear, scratches on the surface of the lens. Compared with the glass sheets, the hardness of organic materials is relatively low, and it is easier to produce scratches. Through the microscope, we can observe to scratch the surface of the lens is mainly divided into two, one is due to the gravel scratches, shallow and small, wearing glasses is not easy to detect; another is generated by the larger gravel scratches and deep and surrounding rough in regional center will affect visual acuity test method for estimation and testing of abrasion resistant film wear resistance of the most fundamental method to be of clinical use, let glasses wearers for a period of time, then observed with a microscope and compared with lens wear. Of course, this is usually in the new technology before the formal promotion of the method used, at present we commonly used more rapid and intuitive test method is:

1) scrub trial will be optical lens are placed in filled with gravel propaganda (set of gravel size and hardness) and in certain under the control of back and forth friction. After the end of the fog, the amount of light before and after friction was measured and compared with the standard lenses.

2) test the steel wool with a specified steel wool, under certain pressure and velocity, in the number on the surface of the lens friction to and with Haze Meter before and after the friction test lens light diffuse reflection, and compare it with the standard lens.

3) the anti reflective coating on the surface of the lens is a very thin inorganic metal oxide material (thickness less than 1 microns), hard and brittle. When plated on the glass lens, the film base is relatively hard, gravel in the above across. The film is less prone to scratches; but anti reflection film is plated on the organic lens, the film base is relatively soft, gravel across the film. The film is very prone to scratches.