Lens is one of the most important components of a pair of glasses, and the quality of the lens directly affects the quality of the glasses. With the improvement of living standards, the prices of many high-end brand glasses are also very high. We have spent a lot of money and definitely hope to buy a good pair of glasses. For example, the current popular plate glasses, metal glasses, or cowhorn glasses have a rich variety of styles and colors. Choosing a pair of glasses that you like in appearance is definitely easy, but the functionality of the lenses is also important. And the lens is the most important functional component of a pair of glasses. Let’s take a look at how glasses factories inspect the quality of lenses. Of course, if you are an ordinary consumer, I also hope it will be helpful to you.

1. Appearance inspection. For other surface issues such as color, noise, pitting, scratches, etc. Place a piece of pollution-free white paper underneath and carefully examine whether there are any of the above issues under QC lighting (stronger and more uniform lighting than regular sunlight).

2. Specification inspection. The main tools include oil level calipers, thickness gauges, and curvature gauges. Measure the diameter of the lens using an oil gauge card, measure the thickness of the lens using a thickness gauge, and measure the actual curvature of the lens using a curvature gauge.

3. Anti friction test. Rub a certain amount of rough paper, cloth, or other material back and forth on the surface of the lens with a certain amount of force, and then observe the effect. High quality eyeglass lenses have good anti friction effects.

4. Adhesion test. Commonly used methods include hundred grid testing and using a knife to cut. Face grid test is to use a blade to cut small squares on the surface of the lens, then use transparent adhesive to stick and tear, repeat several times, and observe the effect.

5. Impact resistance test. Also known as drop ball testing, using a drop ball testing machine to test the impact resistance of lenses.

6. Lens function test. Firstly, it is necessary to determine the specific functions of the lens and then conduct corresponding tests. Common ones include anti oil, waterproof, reinforced, UV400, polarized light, etc.

A. Oil proof function test: Use an oil pen to draw on the surface of the lens. If it can quickly gather together, gently wipe it off with the lens, indicating that it has an oil proof function. Observe the degree to which the oily water gathers and is wiped clean, and evaluate its oil proof effect.

B. Waterproof function test: Place the lens in clean water and remove it. With a gentle shake, the surface water will fall off, indicating that the lens has waterproof function. Evaluate the waterproof effect based on the degree of drop.

C. Enhanced function test: Observe under QC light whether there is a transparent adhesive layer on the surface and around the lens, and gently wrap it with a blade to ensure good strength and toughness.

D. Polarization function test: Use a polarizer for testing. Alternatively, open the computer WORD document and rotate the lens clockwise, facing it. The color of the lens will be light to dark and then all black, and continue to rotate, gradually turning from black to light. It is a polarizer. Pay attention to observing the uniformity of color, and whether it is black enough to determine the quality of polarization function when it is not transparent. The simplest way to check whether the lenses are polarized is to stack the two polarized lenses vertically without any light passing through, which is called polarized glasses.

E. UV400 means 100% UV blocking. Not all sunglasses on the market may have the effect of isolating ultraviolet rays. To know if the lenses can isolate ultraviolet rays: find a UV money detection lamp and a 100 yuan bill. Directly irradiating the RMB can reveal the 100 yuan ultraviolet anti-counterfeiting effect. If separated by lenses with UV400 function, anti-counterfeiting cannot be seen. The US dollar should have the same effect.

The above are some inspection and testing methods for lenses. Of course, there is no absolute standard for it, and the requirements for lenses vary from customer to brand. Some focus more on appearance, while others focus more on functionality, so the focus of inspection will also be different.