Lens index is the value indication of the lens thickness. There are many levels of index lenses, but we will mention the most common indexes such as 1.56, 1.60, 1.67, and 1.74 lens indexes.
The higher the lens index, the more difference in its ability to bend or refract the light and also the thickness of the plastic lens. The calculation of the lens index curve will indicate the choices for thinner and lighter lenses.
Tips: Choose the size of the frame wisely. Choosing the right frame for the wearer is essential. Choosing the smaller size of the frame can also help those who have very high eye numbers; the thickness of the lens will look thinner with a smaller frame and lighter in weight.
This is the standard plastic lens. This lens index is suitable for the eye numbers ranging approximately from 0.00 to +3.50 and from 0.00 to -3.50.
However, this 1.5 index may be the choice for the wearer who has higher eye numbers than these if they do not mind the thickness of the lens in the final result.
Please note that the material of the 1.5 lens index is not suitable for the frame that needs drilling through the lens. Therefore, if the buyer choose the drilling type of frame, then our system will automatically not allow the buyer to choose the 1.5 lens index.
From the index 1.6 and higher are called High Index or sometimes it is called Thin Lens. This 1.6 lens index is suitable for the eye numbers from 0.00 to +5.00 and 0.00 to -5.50 approximately. The buyer with higher eye numbers than these may also buy this 1.6 lens index if the thickness is not a problem for you. The material of the 1.6 lens index is most commonly used because the price is not very high around medium range, it is also thinner and lighter, and it is suitable for any type of frames and also the drilling type.
This lens index of 1.67 is very thin lens. This lens index is suitable for the eye numbers from around +3.00 to +10.00 and from -3.00 to -10.00 or higher. For the buyers who have high eye numbers and are really concerned about the thickness and the weight of the eyeglasses, then this lens index is the best choice. Though the finished eyeglasses will come out nicely thin, the price for this very thin lens is also quite high.
This 1.67 lens index is most commonly used also in the market. The price is quite high but the lens is also very thin and much lighter. The material is plastic and durable, good for the drilling type of frame and any other types.
This 1.7 lens index is known as The Thinnest Lens. Thus, the lens is highly recommended to those who have very high eye numbers like +4.00 to +12.00 and -4.00 to -18.00. If the price is not your concern, but the look and feel of your eyeglasses are, then the lens index of 1.7 is for you. Let’s say that if you have eye numbers of around 5.00 and you use the lens index of 1.7 for your eyeglasses (frame), people may see and think you have only 3.00 eye numbers. This means that it will help your eyeglasses look less bulky.