Leonard Rosenman: Oscar-winning film composer who introduced modernism into Hollywood movie scores

Four dozen films after 46 years in Hollywood might seem a slender output but Leonard Rosenman was determined to compose as he saw fit, and his outspoken criticism of musical illiteracy lost him some commissions. But those who kept faith were often richly rewarded. Rosenman mixed avant-garde techniques with deep psychological insight: "Write sad music for a sad scene – sure, I'll do it; but it doesn't offer me a great challenge."

Rosenman was born in Brooklyn, New York in 1924. He served in the US air force during the Second World War, then attended the University of California, Berkeley, where he graduated with a degree in music. He studied composition with Arnold Schoenberg, Roger Sessions and, at Tanglewood on a fellowship, Luigi Dallapiccola.

In the early 1950s, while living in New York, he met James Dean at a party. They became friends and Rosenman taught him the piano and wrote music for the play Dean was appearing in: Ezra Pound's translation of Sophocles' Women of Trachis. When Dean took Elia Kazan to a concert of Rosenman's music, the director commissioned him to score East of Eden (1955), though both Aaron Copland and Leonard Bernstein had to encourage him to accept.

In the 1950s, younger composers were beginning to look beyond the "Golden Age" style of Max Steiner and Miklos Rózsa. Rosenman was in the vanguard, challenging it with more modernist music, and opening the door for others to follow. Where East of Eden might have suggested a traditional "American-epic" score, Rosenman looked deeper, providing Copland-esque Americana but then giving it an expressionist twist and a dash of jazz to create what he described as "a new and imaginative reality". Composing on set helped him to catch the film's mood, and the music was ready almost as soon as shooting was finished. Unsurprisingly Rosenman was signed up for Dean's next film, made the same year, Rebel Without a Cause, again giving the appropriate lushness a darker underside.

Amazingly, in 1955 he also produced a third standout score. Set in a psychiatric hospital, The Cobweb risked descending into overwrought melodrama but Rosenman, intending to show "what was going on inside characters' heads", countered it with Hollywood's first foray into dodecophony and a solo piano part inspired by Schoenberg's Concerto. Rosenman excelled in such fare and for Sybil (1976), another story of psychiatric difficulty, the orchestra includes two pianos, tuned a quarter-tone apart to evoke the heroine's fragmented personality.

From 1959 onwards, television provided a regular income with projects from the cult The Twilight Zone (1959), through Marcus Welby M.D. (1969) and The Alfred Hitchcock Hour (1964-65).

For Fantastic Voyage (1966), he rejected the producers' idea of having a jazz score to create "the first hip science-fiction movie". The film's premise risked B-movie ridicule as a group of scientists including Raquel Welch are miniaturised to enter a man's body, but again Rosenman cranked up the tension, only scoring the second half of the film and filling it with rhythmically driving music and dissonant Ligeti-like clusters, finally resolving at the end into clarity. Ligeti also inspired his "tortured crawling" music for the Second World War-set TV series Combat! (1963).

Though an animated version of The Lord of the Rings (1978) included a traditionally upbeat striding theme and a limpid children's choir, there were also labyrinthine melodies and dark, curdling harmonies. At one point the choir intones "Dranoel Namnesor" – the composer's name spelt backwards. The soundtrack LP was popular, but the film failed and one of Rosenman's own favourite scores lost the longevity it deserved. Rosenman didn't only seek psychological authenticity; for A Man Called Horse (1970) he eschewed traditional "Hollywood Indian music", preferring to draw on the genuine article.

On several occasions Rosenman was drafted in to pick up franchises from other composers: his score for Beneath the Planet of the Apes (1970) is every bit the equal of Jerry Goldsmith's groundbreaking original, though Battle for the Planet of the Apes (1973) is less inspired and RoboCop 2 (1990) misses the film's satirical humour. For Star Trek IV: the voyage home (1986), Rosenman was faced with a frantic production schedule, and his is the shortest Star Trek score.

His score for the Italian film Jurij (2001) included many of his typical touches and the story – of a violin virtuoso – allowed him to write an extended chaconne-concertino for the instrument. Though he developed frontotemporal dementia, a degenerative brain condition similar to Alzheimer's disease, he was still able to work on his music.

Ironically his two Oscars, won back to back in 1975 and 1976, were not for his own ground-breaking scores but for adaptations: of classical music for Barry Lyndon and of Woody Guthrie's songs for Bound for Glory. Picking up the second statuette he joked: "I write original music too, you know!"

Rosenman's cinema success damaged his concert career: after five major New York performances in a single year and sharing the bill with Milton Babbitt, "the minute I did my first film, I didn't have another performance [there] for 20 years". Nevertheless, the Los Angeles Philharmonic commissioned a memorial to his second wife for orchestra and electronics, and his catalogue includes a double-bass concerto, two violin concertos and, in 1996, the "Dinosaur" symphony.

John Riley

Leonard Rosenman, composer: born New York 7 September 1924; four times married (one son, two daughters); died Woodland Hills, California 4 March 2008.