Extension activities for In My Sights
(In My Sights)
Další doplňkové výukové materiály a aktivity k modulu In My Sights.
More articles on the eye to read:
Find everything you need to
know about Short-Sightedness (Myopia) including causes, symptoms, diagnosis and
treatment, with links to other useful resources.
Extension activity 1:
1. Could glasses soon be history?
have identified a gene that causes short-sightedness, a discovery which paves
the way for treatment to prevent one of the world's most common eye disorders.
So could this mean the end of spectacles?
2. A history of glasses
- There had been an awareness of lenses for hundreds of years before the first spectacles were invented.
- Salvino D'Armate is credited with inventing the first wearable eye glasses in Italy in 1284, although there is no evidence he did.
- There is documented evidence of their existence in 1289.
- In the early 18th century an optician in London, Edward Scarlett, added arms to the lenses that hooked behind the ears.
- About 100 years later one of the founding fathers of the US, Benjamin Franklin, invented bifocals.
- At the start of the 20th century there was still some resistance to wearing specticles, although Hollywood stars went some way to tackling this stigma by wearing sunglasses in the 1930s.
- Even today in some countries like Brazil and Argentina, young people try to avoid wearing glasses.
Search for more about the history of glasses and prepare your own presentation.
3. Solve the following word problems.
- When we look at a person with “thick“ glassess, his or her eyes seem to be either magnified or miniaturised. Which person is short-sighted and which is long-sighted? Explain.
- Some people use “half-glasses“. What defect is corrected by such glasses and what kind of lenses are used?
- What optical power do glasses have to have for: a) a short-sighted eye whose further point is at the distance of 10 cm from the eye; b) a long-sighted eye whose near point is 50 cm from the eye?
1. In the case of a short-sighted person we can see his eyes miniturised, because we use a concave lens to correct short-sightedness. The concave lens causes the spreading of parallel light rays passing through.
In the case of a long-sighted person, we can see his eyes magnified, because we use a convex lens to correct long-sightedness. The convex lens causes the convergence of parallel rays passing through.
2. These are glasses perched lower on nose so as not to obscure the upper part of the visual field, which a person uses for distance vision. A person looks through these glasses only when looking down at close up objects. Also, these glasses correct presbyopia.
3. a) -10 dioptres, b) +5 dioptres
4. Answer the following questions:
- What are the main components of an eyeball?
- In which part of the eyeball is the pupil? Why is it important?
- How does the eye adjust to nearby vision and distance vision? Compare the reasons of the most common eye disorders.
5. A cool test for short-sightedness
In My Sights
Tento projekt je spolufinancován Evropským sociálním fondem a státním rozpočtem České republiky.