Yours, Etc.: Origins and Uses of 8 Sign-Offs
in the figurative sense, 1867, from horses wearing blinkers to limit the range of their vision (see blinker).
1630s, "one who blinks," agent noun from blink (v.). As a type of horse eye screen to keep the animal looking straight ahead, from 1789. Slang meaning "the eye" is from 1816. Meaning "intermittent flashing light" is from 1923.