In a highly competitive optical market, some eyeglasses shops will use “low price” to attract more customers. Can the customers benefit from the “sales”? Not really, as it is difficult for a shop to give up his profits. When the customers fit the glasses, the shop assistants usually recommend the high index lenses. As high index refractive lenses are thinner and lighter, under consideration for comfort and beauty, most of the customers will prefer it. Generally, high index lenses would be more expensive than the low ones. In order to guarantee the shop’s profits, some of shopkeepers would try to replace their customer’s expensive lenses. For less understanding of the lenses, the customer can’t find this trick. This bad phenomenon does harm not only to the consumers but also to all good-quality suppliers. To solve this problem, Canton Optics shall recommend you a small useful tool – CT4405 Digital Radian Apparatus (also named digital lens clock). This tool includes 8 regular indexes and could be applied to any material lenses. Only in one step, the accurate index can be shown visually for you. So, our consumers are at ease about their eyeglasses and the shops can build their good credit and reputation in the market.

P.S.: With different index testing modes, the power of the lens will be also different.
Sample:  - 7.50D     n=1.56    actual power: -7.50D 
                                  n=1.61     actual power: -8.25D
                                  n=1.67     actual power: -9.25D