Question

what technique that contrasts larger areas of dark with smaller illuminated areas did caravaggio master?

Answer 1

I'd go with chiaroscuro. Carvaggio wasn't the only one to use this particular technique, either. Many others did as well such as Michelangelo, but Caravaggio was particularly keen on using it in quite a number of his works which are often brought up as among the best examples of the technique.

He would even go on to develop a more extreme version of chiaroscuro which would be termed tenebrism utilizing even sharper contrasts of light and dark to create deeper perceptions of realistic detail.