Abstract: An apparatus for optically recording on a light sensitive record carrier variable measurement quantities that can be transformed into electrical current or voltage variations includes a row of light-emitting elements arranged transversely to the direction of motion of the record carrier and, in addition, an amplitude discriminator arrangement, including an integration arrangement, for addressing such elements. The output of the integration arrangement is connected to the inputs of comparators included in the discriminator, the latter comparators being also addressed, respectively, by the measurement quantities to be recorded. The outputs of the comparators are, in turn, connected to an OR logic circuit which controls an electronic switch. In an auxiliary circuit, this switch is arranged in series with further electronic switches and the light-emitting components. The further electronic switches are actuated by a cyclically operating control device.