"Okada, Shinoda and Tsutaka: Three Pioneers of Abstract Painting in 20th-Century Japan," at the Phillips Collection, is an exhibition out of balance, although there is much that these three artists share. All three of them have managed to reconcile opposites-the new and the traditional, the Western and the Eastern, the fierce and the refined. All three have taken much from New York action painting, but their works aren't pure abstractions. Many of their pictures manage to evoke the foliage, the seashore and landscape of Japan.

Were their works of equal quality, their show would be far stronger. Kenzo Okada, who was born in Yokohama in 1902 but has lived here since the 1950s, is, by any measure, and admirable painter. Beside his subtle canvases those of Toko Shinoda and Waichi Tsutaka seem both rough and thin. They are not in his league.

Kenzo Okada is not a one-note painter; he orchestrates his pictures. He splatters paint and applies it to the canvas in freely brushed calligraphies; he uses many colors, and as many shapes-those of leaves and morning glory blossoms, rough circles, squares and stripes-and yet these disparate components live peacefully together. They never seem to clash.

His pictures suggest something specifically Japanese: No carefully raked rock garden, embroidered robe, lacquered box, paper screen or silk-bordered scroll could remind us more eloquently than these paintings do of the Japanese concern with subtlety of surface.

A number of these paintings, the Guggenheim Museum's "Solstice," for example, or the Phillips' "Footsteps," date from the early '50s, but have lost none of their freshness. The latest works on view are equally entrancing. The right-hand side of "Autumn" (1978) recalls the locked-and-layered abstractions of California's Richard Diebenkorn, but the left half of the painting shows a meadow seared by fall, sprinkled, from above, with beige and brown and orange pointed longstemmed leaves.

Toko Shinoda's Sumi paintings are not without elegance, but beside Okada's complex works they seem chic and overblown. A number of her pictures recall cleaned-up Klines. Franz Kline liked the loaded brush, the single sweeping gesture; so does Shinoda. Her palette is restrained. She likes black on white, or silver, with here and there a highlight of bright green or bright red. Occasionally her brushstrokes suggest the branches of the willow or reeds bent by the wind.

Of the three painters represented, Wichi Tsutaka is the most uneven.However, a number of his pictures-"Emptiness" (1961), "Motion" (1969) and "Encounter" (1974)-beautifully suggest the sound of surf, islands seen at night and reflections on the sea.

The Phillips exhibition is part of the "Japan Today" symposium, a seven-city "celebration of the people and culture of modern Japan," funded by both National Endowments, Matsushita Electric (Panasonic), the Japan Foundation and the Japan-United States Friendship Commission, and sponsored and organized by the Japan Society, Inc., Meridian House International and the Smithsonian Resident Associate Program.

"Okada, Shinoda and Tsutaka: Three Pioneers of Abstract Painting in 20th-Century Japan" will begin a 10-month national tour after closing at the Phillips on May 26. CAPTION: Picture, Kenzo Okada