COURSE OF OUTPUT-INPUT RATIO IN RELATION TO FREQUENCY AND STATE OF ADAPTATION MEASURED AT A SINGLE PHOTO-RECEPTOR IN COMPOUND EYE OF CALLIPHORA ERYTHROCEPHALA

1. Light potentials of single photo-receptors in the compound eye of Calliphora are measured by means of intracellular recording. The receptor is stimulated by sine-modulated light with a modulation-degree of 20 %. 2. The frequency-course of the amplitude and the phase lag is recorded at different states of adaptation. 3. The photo-receptor represents a non-linear system. The supposition of a real time lag seems to be absolutely necessary. 4. The sensitivity of the photo-receptor is presented as function of frequency and state of adaptation. 5. From the dynamic measurements as stationary limiting-case there results a logarithmic function between receptor-potential and light intensity. © 1969 Springer-Verlag.