Progressive lens
Progressive lens are a type of optical lens used in eyeglasses to correct presbyopia and other disorders of accommodation. They are characterised by a gradient of increasing lens power, added to the wearer's correction for the other refractive errors. The gradient starts at the wearer's distance prescription, at the top of the lens and reaches a maximum addition power, or the near prescription, at the bottom of the lens. The length of the progressive power gradient on the lens surface depends on the design of the lens, with a final addition power between 0.75 and 3.50 dioptres for most wearers. The addition value prescribed depends on the level of presbyopia of the patient. In general the older the patient, the higher the addition.
History[edit | edit source]
The concept of progressive lens has been around since the late 19th century, but it was not until 1959 that the first commercially viable solution was developed by Bernard Maitenaz, who was working for the French company Sociedad Española de Óptica (SEOR), later to become Essilor. The lens, commercially known as Varilux, has been continually improved and remains a market leader.
Design[edit | edit source]
Progressive lenses are designed to provide a natural correction of presbyopia by smoothly varying the lens power to provide clear vision at all distances. The lens power is determined by the specific needs of the wearer, and can be adjusted to suit specific tasks, such as reading, using a computer, or driving.
Advantages and Disadvantages[edit | edit source]
The main advantage of progressive lenses is the ability to provide clear, seamless vision at all distances. This eliminates the need for separate glasses for distance and reading, and allows the wearer to perform all tasks without changing glasses. However, some people may experience difficulty adapting to these lenses, and may experience a "swim" effect due to the changing lens power. This can usually be overcome with time and practice.
See Also[edit | edit source]
References[edit | edit source]
| Progressive lens Resources | |
|---|---|
|
 |
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
|
WikiMD's Wellness Encyclopedia |
| Let Food Be Thy Medicine Medicine Thy Food - Hippocrates |
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD
