Hyperopia: When the Near Point Is Pushed Out

1 · Predict

A hyperopic (far-sighted) eye can't accommodate enough to focus on nearby objects — its near point is farther than the normal 25 cm. Does a more severe hyperopia (a farther-out near point) require more or less corrective lens power?

• A farther-out near point needs less corrective power.
• Corrective power doesn't depend on how far out the near point is.
• More — a farther-out near point needs a stronger converging lens to bring close objects into the eye's limited focusing range.

2 · Set Up

1. Open the hyperopia preset and press Reset. This eye's near point is pushed out to 100 cm — anything closer appears blurred.
2. Enable the corrective-power readout.
3. Set the eye's near point for each trial (exploring different hyperopia severities) and record the corrective lens power needed.

3 · Collect Data

Plot corrective power P (y-axis) against near point (x-axis) for your three trials.

4 · Analyze

1. For one trial, compute P = 1/0.25 − 100/near point (cm), giving diopters. Compare to the table.
2. Explain why P comes out positive — hyperopia is corrected with a CONVERGING lens, which images a normally-close object (at the standard 25 cm reading distance) out at the eye's actual (pushed-out) near point instead.

5 · Extend

1. Reading glasses (a common over-the-counter form of hyperopia correction) come in standard positive-diopter strengths like +1.00, +1.50, +2.00 D. Explain, using your data, why someone whose near point is pushed out much farther than normal would need a higher-power pair.
2. Age-related presbyopia (stiffening eye lens) and true hyperopia (an eyeball shape issue) both push the near point outward and are corrected the same way, with converging lenses — but they're different underlying causes. Why might both conditions still use the same 'add reading power' correction formula?

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