| 摘要 |
By means of a light-sensitive device, which comprises a photosensitive electrode 10, the changes in composition of a medium can be measured at one or more sites close to the electrode. With a light source 32, the measurement site or sites on the electrode surface is/are irradiated, and, by means of an electric circuit 11 which comprises a voltmeter 16, the potential of the electrode 10 is measured in relation to the counter-electrode 15 and, if appropriate, a reference electrode 14. A change in the potential can be ascribed to a given change in the composition of the medium at the measurement site. <IMAGE> |
