Adjustable glasses, also known as adjustable focus glasses or self-adjusting glasses, are a type of eyewear designed to allow users to adjust the focus of the lenses themselves without the need for prescription eyeglasses or optometrist services. These glasses are particularly helpful for people with presbyopia, a common age-related condition that affects the eye’s ability to focus on nearby objects.

Here’s how adjustable glasses work:

1. Fluid-filled lenses: The glasses have lenses filled with a special fluid, typically silicone or glycerin, placed between two flexible membranes.

2. Adjusting the focus: By using a small dial or slider on the glasses, the wearer can change the amount of fluid between the membranes, thus altering the curvature of the lenses. This adjustment changes the focal length, allowing the user to focus on objects at different distances.

3. Customization: Adjustable glasses can be personalized to suit an individual’s vision needs, and the focus can be fine-tuned to provide clear vision for various distances, such as reading, computer work, or viewing objects in the distance.

While adjustable glasses can be a convenient solution for some individuals, they might not be suitable for everyone. Those with complex vision issues or significant refractive errors might still require traditional prescription eyeglasses. Additionally, it’s essential to consult an eye care professional to determine the most appropriate eyewear for your specific vision needs.