Richard Diebenkorn's supreme achievement, "The Ocean Park Series," is a treasury of 20th-century American art.

The West Coast artist's career started in our area when he was stationed in the Marines at Quantico in 1943. Diebenkorn worked in the photographic section, making maps. He also did portraits of fellow servicemen for them to send home as Christmas gifts.

He visited the art galleries in Washington, D.C, particularly the Corcoran Gallery, the National Gallery of Art and the Phillips Collection, where he studied the works of Henri Matisse, Pierre Bonnard, George Braque, Paul Cezanne and Pablo Picasso. He also began his first abstract watercolor during this time.

Someone would later say that Diebenkorn's colors are like those of Matisse, with cubist structures, and perhaps Monet's light on water effect.

Using his GI bill, Diebenkorn went to the University of New Mexico in Albuquerque, where he mapped worlds of desert beige, orange, reds and pinks in his early abstract canvases.

A plane flight from New Mexico to San Francisco in 1950 had lasting impact. He observed the aerial view, noting the possibilities for a painter of "forms operating in shallow depth."

In San Francisco, he studied under the leading figures in American Abstract Expressionism--Mark Rothko and Clyfford Still.

Then he moved to Ocean Park, a beach-side community in San Monica. In 1967, he began this series in which factors like his mapping skills, the influence of the abstract expressionists and his fascination with color, light and space converged in these masterpieces of modern abstraction.

Of the almost 500 paintings, prints and drawings in this series, about 80 are in this exhibit.

The aerial views are not landscapes drawn from the vantage point of a helicop-ter. These "invented landscapes," as he called them, were done in his studio, created on canvas hung on walls, with the intention that they be viewed vertically, not from overhead.

In large space accompanied by the natural light that the Corcoran atrium-style galleries provide, the large ethereal paintings bypass the need for explanation by the sheer visual pleasure they enkindle.