This was announced by his son, actor Robert Downey Jr. on his Facebook page.
“He was a real free-thinking cinematographer, and to the very end remained an amazing optimist ... According to my stepmother's calculations, they lived in a happy marriage for just over two thousand years,” wrote Downey Jr.
According to the actor, his father died in his sleep after several years of struggling with Parkinson's disease.
Downey Sr. directed more than a dozen films based on his own scripts and directed several episodes of the popular TV series The Twilight Zone.
He was also best known for his roles in Live and Die in Los Angeles, Magnolia and Boogie Nights.