| =============================================== Magnifier Information After the age of about forty you will experience a problem viewing small print and tasks involving close detail
work. This eye condition is called presbyopia and magnification is the answer. Magnifying dome magnifiers are excellent
for the visually impaired and can be of help with macular degeneration. What is a dome
magnifier? A dome magnifier is a dome-shaped magnifying device made of glass or acrylic plastic, used to enlarge words on a page or computer screen. They are plano-convex lenses: the flat (planar) surface is placed on the object to be magnified, and the convex (dome) surface provides
the enlargement. They usually provide between 1.8× and 6× magnification. Dome
magnifiers are often used by the visually impaired. They are good for maps or basic text and their inherent 180° design naturally amplifies illumination
from ambient side-light. They are suitable for people with tremors or impaired motor skills, because they are
held in contact with the page during use. https://en.wikipedia.org/wiki/Dome magnifier =========================================================== What type magnifier is best? Hand held magnifiers are best
for short duration use and a magnifying lamp or hands free magnifier with stand are best for long duration
use. Magnifier glass power and work distance: Select magnifiers with a power that will allow you to perform your task at a comfortable distance. The higher the power of the magnifier the shorter the focal range(work
distance) and the smaller the field of view. The high power magnifier may not be the best magnifier for you. Our
large magnifier selection can help those with presbyopia and macular degeneration.
Field Of View: The size of the area being magnified when viewing through a magnifying lens. The higher
the power of the magnifier the smaller the field of view.
Diopter: Diopter is a measurement that is used to calculate the power of a magnifying
lens. The higher diopter will provide higher magnification. Diopter is expressed as "D" Power: Power is how large an object or print increases as you look through a lens.
Magnifying power is expressed as "X" Focal Length: Measurement
from the center of the lens to to the object and be in focus
Focal Range: The distance from the magnifying lens to the object being viewed. Fresnel Magnifier: A flat magnifier consisting of concentric circles that can be a full page reading magnifier. Visual impairment (or vision impairment) is a decreased
ability to see to a degree that causes problems not fixable by usual means, such as glasses or medication. Our low vision
magnifiers can be of help.
Rules
Of Magnification. - The higher
the power of the lens, the closer you must get to the object being viewed and the smaller the field of view.
- As the
power of a lens increases the diameter of the lens decreases.
- Diopter is a term used
to determine the power(magnification}of a lens. The terms are sometimes confused.
    | 
