What is Plus and Minus numbers related to eye sight?
Date: 27 Oct 2010 Posted By:
What is Plus and Minus numbers related to eye sight? What is 6/6 and 6/24? What is cylindrical and spherical axis related to eye?
and make money!
View All Answers:
30 Oct 2010 Member Level:
Points : 4 (
Myopia or short-sightedness is an eye disease in which the person is unable to see the far objects. It is because the parallel rays from the far objects meet behind the retina after passing through the crystalline lens of our eyes. It may be due to two reasons:
i) Lengthening of the eyeball from front to back.
ii) The crystalline lens of our eyes has become too convex.
It can be corrected by using a concave lens whose power is defined in negative units called Dioptre.
1 Dioptre= 1/focal length.
Note that the focal length must be expressed in meters.
Hyperopia is a disease in which the person is unable to see the near objects. There are two reasons for this;
i) Shortening of the eyeball from back to front
ii) Lens may become too flat with age.
It can be corrected using convex lens whose power is defined in positive units by convention.
Thus a person having positive power has Hyperopia and wears convex lens.
Ex- A +3 dioptre lens converges the rays at 1/3 metres.
Post answer or solution to "What is Plus and Minus numbers related to eye sight?"
from Google AdSense and our revenue sharing programs by posting valid answers for this question.
to post a response.
How to get rid of piles?
which vitamin is most imporant for us?
Any nutrition or products which will give supplement for height
What could be the cause for Chest pain?
How to improve my weight
Give me some tips to reduce weight?
What is Marasmus?
Is there any side effect if we take vitamin suplements regularly
Return to Question Index
Ask Question to Experts
Subscribe to Email
Get Jobs by Email
Forum posts by Email
Articles by Email
Awards & Gifts
Last 7 Days
Dr. Apurva Tamhane
Hafeezur Rahman P
Cijo George Thomas
ISC Technologies, Kochi - India. Copyright © All Rights Reserved.