Which biometric method scans the blood-vessel pattern of the retina?

The biometric method that scans the blood-vessel pattern of the retina is the method referred to as retina scans. Retina scanning involves capturing a detailed image of the unique pattern of blood vessels in the thin layer of tissue at the back of the eye. This pattern is highly unique to each individual, making it a reliable method for verifying identity.

Retina scans offer a high degree of accuracy and can be used in various security applications, such as access control and identity verification systems. The uniqueness of retinal patterns, which are stable over a person's lifetime, contributes to their effectiveness as a biometric modality.

While other biometric methods such as facial scans, fingerprint scanning, and iris scans have their own unique characteristics, they do not involve the same scanning of blood-vessel patterns in the retina. Thus, retina scans are distinctively tied to this specific biometric trait.