Which art movement is notable for its visual emphasis on geometric forms and vibrant colors?

The art movement known for its visual emphasis on geometric forms and vibrant colors is Op Art. This movement emerged in the 1960s and is characterized by its focus on optical effects and the use of visual illusions. Artists within this movement sought to create works that engage the viewer's perception, often using precise geometric shapes and contrasting colors to generate dynamic visual experiences. The manipulation of light and color in Op Art creates a sensation of movement and depth, making the viewer's eyes respond to the artwork in an active way.

Op Art often employs repeated patterns and shapes that can create an illusion of flickering or shimmering, as well as a sense of three-dimensionality on a flat surface. Notable artists associated with Op Art, such as Bridget Riley and Victor Vasarely, explored these concepts extensively in their works. This use of geometry and color is central to the identity of the movement, distinguishing it from other styles like Expressionism, which focuses more on the emotional and subjective experience rather than strict formal qualities.