Russell Kirsch, a pioneering computer scientist credited with inventing the pixel and developing the first digital image scanner, has died at the age of 91.

Kirsch scanned a photograph of his infant son Walden in 1957, producing the first digital image decades before other early developments in digital photography began to take shape. He died Tuesday at his home in Portland, Oregon, according to The Oregonian.

"My dad, he was a super curious guy, always asking questions," Walden Kirsch told the paper. "He was an iconoclast. When people said you can't go there or you can't do that, he did."

The elder Kirsch was born in New York City in 1929 to Jewish immigrants from Russia and Hungary. After graduating from the Bronx High School of Science in 1946, he attended college at New York University, Harvard and the Massachusetts Institute of Technology.

Kirsch made the digital imaging breakthrough six years into his 50-year career while working in Washington, D.C. for the National Bureau of Standards, which is now known as the National Institute of Standards and Technology.