Miriam Weber and co-workers  developed a microsensor system that can be operated under water while diving - the so called Diver-Operated Microsensor System, or DOMS (Weber et al. 2007).
Since the first prototype, the DOMS has been enhanced to allow underwater measurements of light spectra using a fiber-optic microprobe and to view results on a computer screen while measuring.
More information available from Miriam Weber (m . w e b e r h y d r a - i n s t i t u t e . c o m) and Lubos Polerecky (contact)