Ravi Optician

So, are you looking at your prescription and trying to fathom it out?

Don't worry! In the first instance please speak to your Optometrist. You may have also heard your Optometrist use the terminology of 'Astigmatism', 'Myopia', 'Hypermytropia' and 'Presbyopia'. Never be to afraid to ask your Optometrist if you don't understand something - but to help, below are some quick explanations of these common conditions.
Astigmatism
Astigmatism is the optical term for more than one point of focus. It occurs when the surface of the cornea or crystalline lens is not spherical. Light from an object may focus on the retina in one direction but not the other. An astigmatic eye has curves that are steeper in one direction than the other, like a rugby ball. A normal, spherical eye has curves that are the same in all directions, like a football. An astigmatic person will have distorted vision.

Positioning a cylindrical lens in front of an astigmatic eye will refract the light in one direction more than in the other.The power of the lens is not the same all over. It is stronger in certain areas to compensate for the irregular curves on the astigmatic eye.

When corrected, an astigmatic person will then see distance and close objects clearly.

Myopia
A person with myopia might find it is more commonly referred to as "short sightedness".

What is it?
It is where the image is formed in front of the retina. This could be because the eye is too long, or the cornea or crystalline lens bends the light too steeply.

How does it affect the person?
A myopic person has blurred vision when looking at objects in the distance, and clearer vision when looking at objects close to them.

How can we rectify it?
By placing a concave lens in front of a myopic eye, the image is moved backwards and focuses correctly on the retina. A myopic person will then see distance and close objects clearly.

Hypermytropia
A person with hypermytropia might find it is more commonly referred to as "long sightedness".

What is it?
It is where the image is formed behind the retina. This could be because the eye is too short, or the cornea or crystalline lens does not refract the light enough.

How does it affect the person?
A hypermetropic person has blurred vision when looking at objects close to them, and clearer vision when looking at objects in the distance.

How can we rectify it?
By placing a convex lens in front of a hypermetropic eye, the image is moved forward and focuses correctly on the retina. A hypermetropic person will then see distance and close objects clearly.

Presbyopia
Vision with Presbyopia - w ith Presbyopia the elasticity of the lens is gone, causing light to be focused behind the retina. This can lead to blurring and an inability to focus on objects close to the eye.

Presbyopia classic symptoms:

• A need to hold books at arms length.
• Difficulty focusing on small close objects.
• The need for brighter, direct light when reading.
• If you are short-sighted, having to take off your glasses to see close objects.
• Fatigue, headaches or eye strain when reading.

The good news is that glasses or contact lenses with varifocal lenses can easily rectify Presbyopia. Your optician will recommend the best choice for you.