Italian researchers say they have been able to reconstruct for the first time, stroke by stroke, how Renaissance master painter Leonardo da Vinci created his works of art.

Investigators at the University of Florence have uncovered Leonardo's method of creating his works by using a scientific device to analyze the painting Madonna of the Yarnwinder.

Artist and inventor Leonardo da Vinci, who died in 1519, is known for his vivid, lifelike paintings such as the Mona Lisa.

In the oil painting, completed in 1501, Leonardo depicts the Virgin Mary holding the child Jesus, who is looking at a yarnwinder being used to spin yarn.

"For the first time we have managed to reconstruct his work step by step, like as if watching him while he painted," said Cecilia Frosinini, one of the researchers.

"We have been able to understand what type of painting materials he used, how many layers of colours were applied, and in what thickness and sequence."

The researchers used what they call a nuclear accelerator device that launches particles at high speed to decipher the painting technique.

The examination showed that Leonardo applied thin layers of paint directly on the canvas. Different colours were layered on top of one another to create a rich texture.

Leonardo, who died in 1519, is considered among the greatest painters of all time, renowned for his Mona Lisa and The Last Supper masterpieces.

The artist, who was also a scientist and inventor, was largely self-taught and left works of art that are acclaimed for their vivid and lifelike qualities.

His painting techniques and futuristic designs continue to attract scientists.

A high-resolution 3-D laser scan of the Mona Lisa by Canada's National Research Council in 2006 revealed the woman who sat for the Mona Lisa painting may have been pregnant or just given birth.

Scientists discovered the Mona Lisa was wearing a translucent gauze garment over her dress — a garment known to be worn by women of the time during or after their pregnancy.