Presbyopia and Its Correction

Q.

The lens which is used to correct myopia (shortsightedness) is

1. Both convex and concave

2. Concave lens

3. Converging lens

4. Convex Lens

Q.

What is hypermetropia? State the two causes. With the help of labelled ray diagram, show

(i) Eye defect

(ii) Correction of Hypermetropia

Q. What is presbyopia ? Write two causes of this defect. Name the type of lens which can be used to correct presbyopia .

Q.

Gradual weakening of ciliary muscles with age causes:

1. Myopia

2. Hypermetropia

3. Presbyopia

4. cataract

Q.

The crystalline lens of people at old age becomes milky and cloudy. This condition is called:

1. Myopia

2. Hypermetropia

3. Cataract

4. Presbypoia

Q.

A person suffering from an eye defect uses a lens of power -1D. Name the defect he is suffering from and the nature of the lens used

Q. What is the difference between least distance of distinct vision and near point?

Q.

1) state two practical use of convex lens and concave lens?

Q.

For what kind of defect a person is asked to wear bifocal lens

Q. A convex lens is made of 3 layers of glass of different materials. A point object is placed on its axis. The number of images of the object are?

Q.

Name the lens involved in the following diagram:

1. Convexo – Concave

2. Concavo – Convex

3. Biconvex

4. Biconcave

5. Plano-convex

Q. What is the other name of old age hypermetropia ?

Q. A person can read a book clearly only if he holds it at an arm's length from him. Name the defect of vision :
(a) if the person is an old man (b) if the person is a young man

Q. Name the defect of vision in which the eye-lens loses its power of accommodation due to old age.

Q.

One of the reasons for myopia is

1. shortening of eye ball

2. irregular change in focal length

3. older age

4. elongation of eye ball

Q.

Above picture is a bi-focal lens, used to correct a presbyopic person, what is region 1 and 2?

1. Convex and Concave

2. Concave and Convex

3. Both are concave

4. Both are convex

Q.

What is Convex Lens Used for?

Q.

What is vision defect? What are its types?

Q. What is the lens formula of a convex lens?

Q. What is myopia?

Q.

Which part of bi-focal lens should a person use to read? And why?

1. Lower part , since it facilitates distinct vision

2. Upper part , since it facilitates near vision.

3. Lower part, since it facilitates near vision.

4. Upper part , since it facilitates distant vision.

Q.

Which part of the bi-focal lens should a person use to read? And why?

1. The lower part, since it facilitates distinct vision.

2. The lower part, since it facilitates near vision.

3. The upper part, since it facilitates near vision.

4. The upper part, since it facilitates distant vision.

Q.

A bifocal lens is used for the correction of ____. The upper part of the bifocal lens is a ____ lens and the lower part is ____.

1. presbyopia, converging, diverging

2. presbyopia, diverging, converging

3. hypermetropia, diverging, focusing

4. myopia, converging, diverging

Q.

What is presbyopia?

1. The power of accomodation of the eye usually decreases with aging

2. It is a defect in which presbypoic person lose their ability to change focus.

3. both a and b

4. none of these

Q. 1.what type of concave lens is present in the spectacles of a person with minus power?Is it convexo concavo lens , plano concavo or double concave lens?

Q. Where does the image form in eye in the case of presbyopia

Q.

What corrective lens should a person use who is affected by myopia and hypermetropia?

1. Cannot be corrected.

2. Bi-focal lens

3. Concave lens

4. Convex lens

Q. A bifocal lens is used for the correction of ___. The upper part of the bifocal lens is a ___ lens and the lower part is ___.

1. presbyopia, converging, diverging
2. myopia, converging, diverging
3. hypermetropia, diverging, focusing
4. presbyopia, diverging, converging

Q. The power of corrective lens used for which defect has a positive power?

1. Glaucoma
2. Myopia
3. Hypermetropia
4. Cataract

Q.

What are the symptoms of presbyopia?

1. Difficulty reading fine print, particularly in low light conditions

2. Blur at near or momentarily blurred vision when transitioning between viewing distances

3. All of these

4. Eyestrain, when reading for long periods