Roca cape lighthouse in Portugal, West most point of Europe ( Cabo da Roca) Vertical. Roca cape lighthouse in Portugal, West most point of Europe ( Cabo da Roca) Vertical. The obelisk with a large white cross at Cabo da Roca. It is a cape which forms the westernmost extent of mainland Portugal and continental Europe.
The other rows contain letters that are progressively smaller. During an eye exam, your eye doctor will ask you to find the smallest line of text letters that you can make out, and ask you to read it. If you can read the bottom row of letters, your visual acuity is very good.
The examination will assess visual acuity, color vision, peripheral vision, eye movements, and the appearance of the retina and optic nerve (by looking at the back of the eye). To check peripheral vision, an automated test is commonly used, in which the patient pushes a button every time a flash of light is seen.