What causes nearsightedness?
Nearsightedness usually occurs when the eyeball is slightly too long. This means that light does not focus properly on the light-sensitive tissue (retina) at the back of your eye. Instead, the light rays focus just in front of the retina, causing distant objects to appear blurred. Myopia often runs in families, but it has also been linked to focusing on close-up objects, such as books and computers, for long periods of time.
How do I know if I am nearsighted?
Signs that you may be nearsighted include:
- Difficulty reading street signs and car number plates
- Trouble seeing words on a whiteboard or television screen clearly
- Squinting to see better
- Frequent headaches or tired eyes
How can nearsightedness be corrected?
What causes farsightedness?
Farsightedness usually occurs when the eyeball is slightly too short. This means that light does not focus properly on the light-sensitive tissue (retina) at the back of your eye. Instead, the light rays focus behind the retina, causing nearby objects to appear blurred. Hyperopia often runs in families, but it is also linked to age and certain medical conditions such as diabetes. Age-related farsightedness is known as presbyopia.
How do I know if I am farsighted?
- Difficulty focusing on objects nearby
- Squinting to see clearly
- Frequent headaches
- Eye fatigue when reading, writing or using digital devices
How can farsightedness be corrected?
In most cases, farsightedness can be corrected effectively with convex single vision lenses. These refocus the light correctly on the retina. If you are farsighted, your prescription will be a positive number. The higher the number, the stronger your lenses. If you are concerned about your vision or notice that it has changed, contact your nearest Hoya Vision optician.
What causes presbyopia?
Also known as age-related farsightedness, presbyopia usually affects people over the age of 40. It is a gradual thickening and hardening of the lens of your eye. As the lens loses its elasticity, the ability to focus on nearby objects declines. Presbyopia can be accompanied by other vision problems such as nearsightedness, farsightedness and astigmatism.
How do I know if I am presbyopic?
- Increasing difficulty focusing on nearby objects
- Holding books, newspapers, digital devices and so on at arms length in order to read them properly
- Frequent headaches and eye fatigue
How can presbyopia be corrected?
In most cases, presbyopia can be corrected effectively with progressive lenses. These contain a plus prescription for near vision at the bottom of the lens and a prescription for distance vision at the top of the lens. If you are concerned about your vision or noticed that it has changed, contact your nearest Hoya Vision optician.
What causes astigmatism?
Astigmatism occurs when the transparent layer of tissue (cornea) at the front of your eye is not perfectly curved. This irregular curve means that light rays entering your eye focus in two different places on the light-sensitive tissue (retina) at the back of your eye. This creates a blurred image. Astigmatism is usually present at birth and may accompany other vision problems such as nearsightedness and farsightedness.
How do I know if I have astigmatism?
- Blurred or distorted vision up close and at a distance
- Trouble distinguishing between vertical, horizontal and oblique shapes
- Confusing letters such as H for N or C for O
- Headaches and eye strain
How can astigmatism be corrected?
In most cases, astigmatism can be corrected effectively with toric lenses. These are specially designed and shaped to compensate for the irregular curve of the cornea that causes astigmatism. If you are concerned about your vision or notice that it has changed, contact your nearest Hoya Vision optician.