Question

: Give reasons.
In old age a bifocal lens is necessary for a person.

Answer 1

Hint: The above problem can be resolved using the fundamentals of the human eye and the knowledge of various diseases relating to the vision of the human eye. Moreover, the concept behind the diseases and its optimum solution can be applied for such situations.


Complete step-by-step answer
When a person becomes old, the functioning of the various organs of the body parts generally falls down to their ineffectiveness. Similarly, the eyesight for the old aged person weakens down and this causes the person to suffer from the various diseases related to the vision like myopia as well as hypermetropia. The myopic eye can be corrected by utilising the concave lenses and hypermetropia is cured using the convex lens. Thus, an old aged person suffering from both myopia and hypermetropia require a bifocal lens, whose upper part is made of concave lens to correct the problem of myopia and lower part is made of convex lens to correct the problem of Hypermetropia.


Note: In order to resolve the given problem, one must be aware of the functioning of various organs related to human eyes. Along with the factors affecting such organs, regarding its functioning. And various defects of vision are to be remembered along with the steps for their treatment. The appropriate knowledge of the type of lens is to be noted, to achieve the optimal solution for the problem.