Riley, Bridget (Louise)

English painter. She is known primarily as a pioneer of op art. After brief experimentation with pointillism and colour-field painting, she developed her characteristic style in the early 1960s, arranging hard-edged black lines in regular patterns to create disturbing effects of scintillating light and movement. Current (1964; Museum of Modern Art, New York) is a fine example of her style.

In the late 1960s she introduced colour and experimented with silk-screen prints on Perspex, though she continued to create works in her familiar black-and-white style. Her work has also included stage design, notably for the ballet Colour Moves (1983).