Direct readout of spectral sensitivity for clinical and research purposes.

The application of spectral sensitivity measurements to clinical problems has been limited by the complexity of calculating the corrections for nonlinearity and non-neutrality of the neutral wedge and for the quantum intensity of the test beam. Asimple electronic system is described which performs all these calculations automatically, as the subject makes the sensitivity setting, and records the sensitivity on an XY plotter. A range of 5 log units is covered with an accuracy of 0.05 log units.