A biophoton (from the Greek βίος meaning "life" and φῶς meaning "light"), synonymous with ultraweak photon emission, low-level biological chemiluminescence, ultraweak bioluminescence, dark luminescence and other similar terms, is a photon of light emitted from a biological system and detected by biological probes as part of the general weak electromagnetic radiation of living biological cells. Biophotons and their study should not be confused with bioluminescence, a term generally reserved for higher intensity luciferin/luciferase systems.
Biophotonics is the study, research and applications of photons in their interactions within and on biological systems. Topics of research pertain more generally to basic questions of biophysics and related subjects - for example, the regulation of biological functions, cell growth and differentiation, connections to so-called delayed luminescence, and spectral emissions in supermolecular processes in living tissues, etc.
The typical detected magnitude of "biophotons" in the visible and ultraviolet spectrum ranges from a few up to several hundred photons per second per square centimeter of surface area, much weaker than in the openly visible and well-researched phenomenon of normal bioluminescence, but stronger than in the thermal, or black body radiation that so-called perfect black bodies demonstrate. The detection of these photons has been made possible (and easier) by the development of more sensitive photomultiplier tubes and associated electronic equipment.
Biophotons were employed by the Stalin regime to diagnose cancer, and their discoverer, Alexander Gurwitsch was awarded the Stalin Prize. Various studies have indicated some potential for photon emission to be used as a diagnostic technique.
Read more about Biophoton: History, Proposed Physical Mechanism, Hypothesized Involvement in Cellular Communication