QUESTION 2 Word Limit = 800 words The eye acts as a converging lens system. Converging and diverging lenses may be used in glasses to correct problems with eyesight. a) Describe the path of light through the eye and explain how light is focused to produce and image on the retina. Then explain how diverging lenses can be used to correct short sightedness and converging lenses can be used to treat long sightedness. You may use diagrams to aid your explanation if you wish. b) The diagram below shows light rays from an object 25 cm in front of an eye converging to a point on the retina at the back of the eye. The eye has a depth of 2.4 cm. Calculate the optical power of the eye. Power = 25 cm 24cm Diagram not to scale retina front of eye- c) The human eye acts as a converging lens system that produces an image on the retina at the back of the eye as shown. Diagram NOT to scale retina front of eye A person with eyesight problems may wear either diverging or converging contact lenses. A short-sighted eye cannot focus on distant objects because the power of the eye is too great. One student with short sight cannot focus on objects further than 1.5 m without wearing her contact lenses. To view distant objects, it is determined that the combined power of her eye and her contact lens should be 41.7 D. Determine the power and type of lens needed to correct her vision. Assume the equations for thin lens apply to both lenses. Distance from eye lens to retina = 2.4 cm d) Converging and diverging lenses may be used in glasses to correct problems with eyesight. The diagram shows three parallel rays of light incident on a diverging lens and the path of the rays after passing through the lens. The diagram is drawn to actual size. Add to the diagram to measure / determine the focal length of the lens. Focal length =