Question

The Influence of Distance Lens Power on Segment Inset:

________ power or _____ lenses cause the eyes to converge slightly more than normal because of their ______ prismatic effect.

A) positive; plus; BO
B) negative; minus; BI
C) concave; minus; BU
D) convex; plus; BI

Answer 1

Positive power, or plus lenses (convex), cause the eyes to converge with a base-out (BO) prismatic effect, while negative power, or minus lenses (concave), result in divergence with a base-in (BI) effect. The correct option is a.

Step-by-step explanation:

The influence of distance lens power on segment inset is determined by whether the lens is positive or negative power.

For individuals with farsightedness, lenses are thicker in the center, known as convex lenses, and these have a positive power with a base-out (BO) prismatic effect.

These plus lenses cause the eyes to converge slightly more than normal. On the other hand, for individuals with nearsightedness, the lenses are thinner in the center, which are concave lenses, and these have a negative power with a base-in (BI) prismatic effect.

These minus lenses cause the eyes to diverge slightly more than normal. The correct option is a.

Answer 2

Positive or plus lenses cause eyes to converge more due to their base-in prismatic effect. These lenses are convex and help correct farsightedness by producing an image farther from the eye.

Step-by-step explanation:

The influence of lens power on segment inset is tied to the prismatic effect induced by the lenses. Specifically, positive power or plus lenses cause the eyes to converge slightly more than normal because of their base-in (BI) prismatic effect. This is because positive power lenses are convex lenses, which are used to correct farsightedness. Individuals with farsightedness wear glasses that have lenses thickest in the center to bring the image into clearer focus. These lenses cause light to converge, so the spectacles produce an image farther from the eye, enabling the farsighted person to see it clearly. On the other hand, negative power lenses, also known as minus lenses, are concave and they diverge light, having the opposite effect, with a base-out (BO) prismatic effect.

Positive power or plus lenses cause the eyes to converge slightly more than normal because of their prismatic effect.

The positive power indicates a converging (convex) lens, as expected. If you examine eyeglasses of farsighted people, you will find the lenses to be thickest in the center. In addition, a prescription of eyeglasses for farsighted people has a prescribed power that is positive.