Vision Conditions and Lens Correction

What is the primary cause of hyperopia (longsight) in humans?

• The eyeball is too long relative to the focusing power of the cornea and lens.

• The eyeball is too short relative to the focusing power of the cornea and lens.

• The cornea is too flat.

• The lens is too curved.

What is the main cause of myopia (shortsight) in humans?

• The eyeball is too short relative to the focusing power of the cornea and lens.

• The cornea is too flat.

• The eyeball is too long relative to the focusing power of the cornea and lens.

• The lens is too flexible.

Which of the following best describes the cause of astigmatism?

• Uneven curvature of the cornea or lens.

• The lens is too stiff.

• The eyeball is perfectly spherical.

• The cornea is overly curved.

What type of lens is used to correct hyperopia?

• Concave lens.

• Convex lens.

• Cylindrical lens.

• Planar lens.

What type of lens is used to correct myopia?

• Convex lens.

• Concave lens.

• Cylindrical lens.

• Planar lens.

What type of lens is typically used to correct astigmatism?

• Convex lens.

• Concave lens.

• Cylindrical lens.

• Spherical lens.

How does a convex lens correct hyperopia?

• By diverging light rays before they enter the eye.

• By converging light rays before they enter the eye.

• By focusing light rays directly onto the retina.

• By scattering light rays evenly across the retina.

How does a concave lens assist in correcting myopia?

• It converges the light rays to focus directly on the retina.

• It diverges the light rays so they can focus on the retina.

• It increases the focal length of the eye.

• It decreases the intensity of the light entering the eye.

Which statement best describes how cylindrical lenses correct astigmatism?

• They correct the uneven curvature by focusing light to multiple focal points.

• They correct the uneven curvature by focusing light to a single focal point.

• They flatten the cornea to reduce irregularity.

• They enhance the flexibility of the lens inside the eye.

What happens if hyperopia is not corrected?

• Images focus behind the retina, causing blurred vision.

• Images focus in front of the retina, causing blurred vision.

• The cornea becomes flatter over time.

• The lens becomes more rigid.