How near vision spectacles work
Near vision spectacles work by making text or objects look larger (magnified). The power (strength) of the lens determines how much bigger text or objects will look.
There are different types of near vision spectacles. This module covers near vision spectacles with:
- A magnification power range between +1.00 (weakest) to +3.00 (stronger).
- la misma potencia en la lente derecha y en la izquierda.
Pregunta
What is the difference between near vision spectacles and prescription spectacles?
- Standard near vision spectacles are ready-made with standard powers. The right and left lenses are the same power. They are usually just for people with near vision problems in older adults (presbyopia).
- Prescription spectacles are prepared individually. They are prescribed after a full eye exam, by a person trained to do this. Prescription spectacles help people with different types of refractive error including distance vision problems (myopia), near vision problems (hyperopia) and astigmatism.
The different parts of near vision spectacles
Near vision spectacles have two main parts:
- Las lentes (micas), que es la parte por la que el usuario mira.
- La montura, que incluye los siguientes elementos:
- Los marcos: la pieza que sujeta cada lente.
- El puente: une los dos marcos pasando por encima de la nariz.
- Nose pads, which are small plastic pieces that sit on either side of the person’s nose. They keep the spectacles in a comfortable position.
- Las varillas (patas): salen del marco y van por un lado de la cabeza y por encima de las orejas.
- The hinge, which allows the spectacles to be folded when not in use.
Debate
Are near vision spectacles available in your area? Where are they available, and in what powers?
Tamaños de montura
Near vision spectacles are usually available in a few different frame sizes.
Esto resulta útil para lograr el mejor ajuste posible para cada persona.
Las dimensiones de la montura varían según el fabricante.
Algunas de las dimensiones que suelen variar de una montura a otra son:
- El diámetro de la lente
- El ancho del puente
- La longitud de las varillas
Some spectacles may have these measurements marked on the inside of the temple.
Actividad
Have a close look at the near vision spectacles available to you.
- ¿Hay diferentes tamaños de montura? En caso afirmativo, ¿cuáles son esas diferencias?
- What powers do they come in?