The optician prescribes a corrective lens of power +2.5D. What does this mean?

Question

Question

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Answer 1

The correct answer is The lens is a combo of 2 convex lenses, with powers 2D and 0.5D

Key Points

A corrective lens with power +2.5D indicates a convex lens.
Convex lenses are used to correct hyperopia (farsightedness).
The power of a lens is measured in diopters (D), which is the reciprocal of the focal length in meters.
In this case, the lens could be a combination of two convex lenses with powers 2D and 0.5D.

Additional Information

Convex lenses are thicker at the center than at the edges and converge light rays that pass through them.
The power of a convex lens is positive, whereas the power of a concave lens is negative.
Opticians prescribe lenses based on the refractive error of the eye to help focus light correctly on the retina.
Regular eye check-ups are important to ensure that corrective lenses are up to date and provide the best vision correction.