If a 60-year-old patient with presbyopia views objects through pinhole glasses, why does image sharpness improve, even though the light intensity decreases?

💡 Explanation

Pinhole glasses improve sharpness by reducing the cone of light entering the eye, increasing the depth of focus artificially, rather than correcting the underlying loss of lens elasticity due to aging. Therefore, clearer images are formed because the image is less sensitive to refractive error, rather than due to changes in pupil dilation or lens proteins.

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