Electroretinograph

An electroretinograph (ERG) is a diagnostic ophthalmic device that measures the electrical responses of the retina to light stimuli, helping clinicians assess retinal function. It is primarily used to diagnose conditions like retinal degeneration, night blindness, and retinal blood flow issues by analyzing bioelectrical signals generated in response to controlled light flashes.

These devices typically include electrodes (often gold, platinum, or silver) placed on the cornea and a reference point on the body, paired with an amplifier to detect and enhance weak electrical signals. They may interface with computers for data storage and analysis, though regulations and supply classifications vary by jurisdiction and intended use.