Lars Olof Lennart Nilsson (24 August 1922 – 28 January 2017) was a Swedish photographer. He was known for his photographs of human embryos and other medical subjects once thought not to be photographable. He was also known for his extreme macro photography. His book, A Child Is Born (1965), featured many of his photographs. He was born in Strängnäs, Södermanland County.
Nilsson died on 28 January 2017 at the age of 94.