If you are over 40, then there is chance that you will need to start considering the utility of multifocal contact lenses. Contact lenses have become more popular throughout every generation, which is a primary reason that multifocal lenses have become more popular. The reason that people in their 40's are the primary benefactors of these types of contact lenses is because they are designed to help treat presbyopia. Presbyopia will primarily affect a persons ability to focus on close objects and most noticeable when trying to read, especially in low light environments. There are several different designs that are being used in multifocal lens construction, so it is important to understand what type of contact lenses you should use.
The most common design is the concentric bifocal design. With this type of contact lenses, the correct for seeing items that are near is located in a small circle that is located at the center of contact. It is then surrounded by a much larger circle that helps with correctly your distance vision. The reason that this design has been so effective is because when people focus on items nearer to them, they tend to focus more intently on the item or get "tunnel vision". However, when looking into the distance the entire cornea is taking in the picture.
Another design for these types of contact lenses is known as the alternative image design. Within these designs, there are specific zones that allow for the correction of near and far sight. When describing this type of lens, it is easiest to picture a bifocal. The top of the contact lenses are for distance viewing and the bottom is for viewing nearer objects. It also designed so that if you look straight ahead, you will be viewing through the bottom part of the distance prescription Because this type of lens has only two zones (near and far) they are great for reading or driving, but can be less useful for mid-range tasks such as working on a computer or watching television.
The third option is the simultaneous image design. This design has proven to be extremely complicated, but has shown promising results. The idea behind this design is to have both near and far vision portions location in front of the pupil at the exact same time. It is then up to your brain to decide which area of the lens to pay attention to and which area to ignore. The reason that creating simultaneous or blended designs can be so complicated is that it intends to only correct the specific problem areas of your eyes, which should lead to the most natural vision.
When it comes to multifocal contact lenses, there are a variety of options available. The three most common options that people choose to utilize include: the concentric bifocal design, the alternative image design, and the simultaneous image (blended) design. All of these designs carry specific benefits and drawbacks so it is important to talk to an optometrist in order to determine which solution is the best for your specific situation.
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