Lens Power

القوة البصرية للعدسة

The optical capacity of a lens or surface to converge or diverge light rays, defined as the reciprocal of its focal length in meters: F = 1/f, expressed in diopters (D).

Quick Decode

Lens power describes how strongly a lens brings light rays together or spreads them apart. For a thin lens in air, power in diopters (D) is 1 divided by focal length in meters: a +2.00 D lens has a focal length of +0.50 m. Positive power converges light, while negative power diverges it.

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References (1)
  1. Keating, M. P. Geometric, Physical, and Visual Optics (2nd ed., Chapters 3 & 4) & AAO BCSC Section 3 (Clinical Optics).