William Lawrence Bragg. Portrait of Sir William Lawrence Bragg (1890-1971), Australian-British physicist and Nobel Laureate. Bragg worked with his father (William Henry Bragg) on the investigation of the reflection of X-rays by crystals. The younger Bragg developed the law relating to X-ray diffraction by crystal lattices, later refining the technique as an analytical tool with his father. He also later devised a method of recording X-ray interference patterns on photographic plates for later study. At the age of 25 W.L.Bragg shared the 1915 Nobel Prize with his father, becoming the youngest ever winner.