Rise Time of the Light Induced Electrical Field across the Function Membrane of Photosynthesis

Abstract

A repetitive laser giant pulse photometer is described which can resolve absorption changes of 0.1% in the time range of 10 ns. With this instrument the following results have been obtained. The rise of the field indicating absorption change in photosynthesis has been measured at 515 nm. The upper limit of the half risetime is about 20 ns. This means that the field formation takes place within this time by a light induced transfer of electrons across the thylakoid membrane.