Daniel Joseph Bradley FRS FInstP MRIA[4][1] (18 January 1928 – 7 February 2010) was an Irish physicist, and Emeritus Professor of Optical Electronics, at Trinity College, Dublin.

In 1957, after four years of part-time study, he was awarded a Bachelor of Science degree in physics by Birkbeck, achieving the highest marks in his final exams in the University of London overall.

Appointed to a lectureship in the physics department at Imperial College London, he set up a research programme in UV solar spectroscopy using rocket technology to reach high altitudes.

He attracted significant funding from a variety of agencies, allowing him to build his department into one of the world's leading laser research centres, involving a total of 65 scientists.

He was head of the Physics department from 1976 to 1980 but he was frustrated by cutbacks and a rule governing the ratio of senior to junior positions, one consequence of which was that he was unable to maintain a long-established chair in optical design.

He received several awards in recognition of his work including: He married Winefride O'Connor and had five children: daughter Mairead and sons Sean, Donal Bradley,[3] Martin and Ronan.