What technique measures the dioptric power of the cornea?

The technique that measures the dioptric power of the cornea is kerometry. This method involves using an instrument called a kerometer, which assesses the curvature of the cornea by measuring the reflection of light as it passes through the corneal surface. The readings obtained from the kerometer can help determine the cornea's refractive power, which is crucial for fitting contact lenses and evaluating certain eye conditions.

Refraction, while related to the overall assessment of vision, focuses on determining the lens prescription needed to correct vision rather than specifically measuring the corneal power itself. Optometry is the broader field that encompasses various aspects of vision care, including examination, diagnosis, and treatment, but does not specifically pertain to the measurement of corneal power. Biometry involves measuring the dimensions of the eye and is often used in planning cataract surgery or other procedures, but it does not focus directly on the cornea's dioptric power. Thus, kerometry stands out as the precise technique for this purpose.