Final answer:
Retina scanners confirm a person's identity by analyzing the unique characteristics of their retina using infrared light.
Step-by-step explanation:
A retina scanner confirms a person's identity by analyzing the unique characteristics of their retina. The retina, located at the back of the eye, contains special cells called photoreceptors that are sensitive to light. These photoreceptors create a pattern of blood vessels and other structures that are unique to each individual, similar to a fingerprint. The retina scanner uses infrared light to capture an image of the individual's retina and compares it to a pre-registered template to confirm their identity.