Progressive eyeglass lenses, also known as progressive addition lenses or PALs, are a type of multifocal lens that provides a gradual change in lens power for people who need both distance and reading vision correction. Unlike traditional bifocals or trifocals, which have visible lines separating the different powers of the lens, progressive lenses have a seamless transition between the various powers, allowing for a more natural viewing experience.
Progressive lenses are designed to correct for presbyopia, a condition that occurs as people age and the eye’s ability to focus on close objects decreases. This condition typically affects people over the age of 40 and can make it difficult to read, work on the computer, or perform other close-up tasks.
Progressive lenses work by providing different powers of correction across the lens surface. The top portion of the lens is for distance vision, the middle portion is for intermediate vision, and the bottom portion is for reading and close-up tasks. This allows the wearer to look through different parts of the lens depending on what they are doing, without the need to constantly switch between different pairs of glasses.
One of the key benefits of progressive lenses is that they provide a more natural viewing experience. With traditional bifocals or trifocals, the line separating the different powers of the lens can be distracting and make it difficult to transition between different visual tasks. Progressive lenses eliminate this issue and provide a smooth transition between different powers, allowing the wearer to move their eyes naturally without having to adjust their head position.
Progressive lenses are available in a wide range of materials, including plastic, polycarbonate, and high-index materials. They can also be treated with coatings to reduce glare and scratches and can be made in a variety of designs to suit different preferences and needs.
In conclusion, Progressive eyeglass lenses are multifocal lenses that provide a gradual change in lens power for people who need both distance and reading vision correction. They are designed to correct for presbyopia, a common age-related condition that affects the ability to focus on close objects. Progressive lenses offer a more natural viewing experience and allow the wearer to look through different parts of the lens depending on what they are doing, without the need to constantly switch between different pairs of glasses.