Inside of the eye is a structure called the Lens. The Lens helps the eye to focus, like a lens in a pair of eyeglasses may help someone to focus. Our Lens allows for us to focus or unfocus, enabling us to view objects at different distances. The Lens of our eye is more dynamic than [eyeglass lenses]. Viewing distance objects requires the eye to relax the Lens, decreasing lens convexity. Viewing near objects requires an increase in convexity of the lens, creating more focus power. This provides us with magnification for close object viewing. From the age of 11, the ability of the lens to change convexity when viewing from distance to near slowly decreases. At first changes are slow. As we approach the age of 40, the ability of the lens to focus on near objects has greatly decreased and within the next 3 years, most people who still can see clearly when viewing distant objects are not able to see print within arms reach. They must hold the newspaper or novel further and further away to see clearly, until they would need to hold the print beyond their fingertips to see it clearly.
The arms have become too short. This phenomenon is known as [Presbyopia]. [Presbyopia] is a condition affecting every person cross-culturally who lives past the age of 40-43. There is no surgical treatment for the condition. The options to help with [Presbyopia] are [bifocal eyeglasses], [contact lenses] or [laser vision correction] modified for [monovision] (one eye for near, one eye for far).
[Nearsighted] people can read very well without eyeglasses or contact lenses well past the age of 40-43. If their distance vision is corrected to 20/20 with [eyeglasses], they will need additional power in the bottom half of the lens to read. This additional power is known as the “[add]” of the lens. The whole lens is known as a [bifocal] (bi-focal, or two focal points). If the patient above 40-43 is corrected to see clearly at distance with [contact lenses], they will need additional power over the contact lenses in the form of [eyeglasses] to see near objects. For [contact lens] wearers, contact lens prescriptions may be modified so that one eye is corrected for close work and the other eye for distance viewing. This is called [monovision]. [Bifocal contact lenses] are also available.
[Farsighted] [(Hyperopia)] implies ability to see well far away, while having difficulty at close. People who are farsighted need help viewing objects at close distances at an earlier age than 40. Since farsighted people have a disadvantage seeing up close even before experiencing [Presbyopia], they need help with near vision earlier than nearsighted people. And get this, people who are very tall, or have long arm length may actually delay needing help of near addition lenses longer than someone with a shorter arm length, literally because their arms are longer! So no, your arms aren’t too short, it’s your eyes that aren’t powerful enough anymore. Additional magnification for people needing assistance for reading, computer work or close work can come in the form of [Reading glasses], [Bifocal lenses], [Trifocal lenses], a [Multifocal lenses], [Monovision Contact Lenses], [Bifocal Contact lenses] or Monovision [Laser Vision Correction].