Basic Opticianry Dispensing revision chapter 1

What is the formula used to calculate near (reading) prescription?

What is the formula used to calculate Addition?

What is the formula used to calculate Distance prescription?

Which structure controls the amount of light entering the eye by adjusting the size of the pupil?

Which part of the eye controls the amount of light entering the eye?

• Cornea

• Sclera

• Pupil

• Iris

Answer explanation

The pupil is the circular opening in the center of the iris that regulates the amount of light entering the eye by dilating or constricting.

What happens to the pupil in dim light?

• It constricts

• It dilates

• It remains unchanged

• It closes

Answer explanation

In dim light, the pupil dilates to allow more light to enter the eye, improving visibility in low-light conditions.

Which anatomical landmark is located at the outermost layer of the eye?

• Limbus

• Iris

• Cornea

• Pupil

Answer explanation

The cornea is the transparent, outermost layer of the eye that helps focus light onto the retina.

What is the function of the limbus in the eye?

• It controls the amount of light entering the eye.

• It is the junction between the cornea and sclera.

• It focuses light onto the retina.

• It provides color to the eye.

Answer explanation

The limbus is the border area where the cornea meets the sclera, playing a role in maintaining the structural integrity of the eye.

Which part of the eye is responsible for focusing light onto the retina?

• Cornea

• Pupil

• Iris

• Sclera

Answer explanation

The cornea is the primary structure responsible for refracting and focusing light onto the retina.

Explain the importance of pupillary distance.