When I first started a business a few years ago, I would go to the office buildings to push and promote the glasses frame that we designed ourselves. In the process, I often encounter some very "smart" customers. No matter how I sell frames to them, they will block them back in one sentence: Don't sell the frames! The frame doesn't matter, so I only need the best lens! I have nothing to debate with him when I encounter such a "smart customer." In their eyes, the lens are the most important, and the quality of frames is nothing to care about. But in fact, the phrase goes that "good horse with a good saddle", which can be applied to choose your glasses. A good frame with a pair of ordinary lenses will not affect the optical performance of the lens and will not cause any harm to our eyes. However, if it is a good lens, it is not mounted on an accurate frame, not only can not play its normal optical performance, but also may cause damage to our visi...