Contact Lens Selection Guide
Many people focus solely on color and diameter when purchasing contact lenses, overlooking comfort and safety. Alternatively, while they may want to choose a comfortable lens, they often feel confused about how to make the right selection.
In fact, by remembering a few important parameters when selecting contact lenses, even beginners can quickly find suitable and comfortable lenses.
1. Material
Contact lenses are primarily categorized into three types: HEMA, Silicone Hydrogel, and Polymacon. There is no single “best” material among these; it is recommended to choose the one that best suits your eye condition.
HEMA
HEMA lenses have a high water affinity and are soft, but they are more prone to protein deposits. If your eyes are generally healthy, this material offers a good cost-performance ratio.
Silicone Hydrogel
Silicone hydrogel lenses provide a balance of oxygen permeability and comfort, and they are better shaped, making them easy for beginners to wear. Generally, these lenses are priced higher and are suitable for individuals who need to wear them for extended periods.
Polymacon
Polymacon lenses are very lightweight and soft, with a lower tendency for protein deposits. This reduces the feeling of foreign bodies in the eye while extending the lifespan of the lenses. For those with sensitive eyes, choosing polymacon lenses can provide greater comfort.
2. Lens Diameter
The diameter of contact lenses refers to the actual size of the lens, including the colored part and the clear edges. Whether the lens diameter is too large or too small can affect the wearing experience.
If the lens diameter is too small, it may restrict the optical area and increase the likelihood of lens displacement. Conversely, if the lens diameter is too large, it could lead to discomfort or even damage to the eyes.
3. BC (Base Curve)
The base curve determines the curvature of the lens surface and directly affects how well the lens fits the eye and the overall comfort during wear. If the base curve is too large, meaning the lens is too flat, it may not adhere well to the eye, increasing the chance of lens displacement. On the other hand, if the base curve is too small, it can cause a foreign body sensation and eye irritation.
Before purchasing lenses, it’s advisable to have an eye exam at a clinic to understand your specific parameters, ensuring you choose the base curve that best suits your eyes.
4. Water Content
In general international classification, lenses with a water content exceeding 50% are considered high water content, while those below 50% are classified as low water content.
Many people believe that a higher water content means less dryness during wear; however, this is not always the case. If the water content is too high, the lens may absorb moisture from the eye after some time, leading to dryness and discomfort.
Therefore, if you typically live in a humid environment or wear lenses for a shorter duration, choosing high water content lenses can indeed provide a softer and more comfortable fit.
Conversely, if you live in a dry environment or need to wear lenses for extended periods, low water content lenses would be the more suitable choice.
In summary, selecting the right contact lenses involves considering various factors such as material, diameter, base curve, and water content.
By understanding your eye’s specific needs and preferences, you can find lenses that provide comfort and clarity. We hope you have a delightful shopping experience and enjoy your new lenses!