| Magnifier Information What
Is A Fresnel Lens? A Fresnel lens for reading
purposes consists of a flat plastic lens with concentric grooves on one surface and a flat surface on the other surface Originally invented by Augustine Fresnel.
The original Fresnel lenses were used to magnify the lighthouse beacon light. A Fresnel lens is thinner and lighted
then a ordinary convex magnifying lens.Wikipedia 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 a full page magnifier can help. 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 full page 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 full page 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.
Informative links: Craft Links Knitting, Crochet, and other Needlecrafts How To Knit How To Knit Beginners How To Sew Basic Sewing Stitches How to Crosstitch How To Do Needlework Reading Links The American Foundation for the Blind The National Federation of the Blind Bookshare National Library Service for the Blind and Physically Handicapped Paths To Literacy Classroom National Eye Institute Optometry Cares American Action Fund for Blind Children & Adults Children's Eye Foundation Sight for Students MD Support National Eye Health Education Program | 
