Size of the Static Pupil as a Function of Wave-length and Luminosity of the Light Incident on the Human Eye

IN the past many investigations have been carried out on the static and dynamic reactions of the human pupil to illumination of the eye using white light. In this respect it seems surprising that little attention should have been directed to the dependence on the wave-length of the incident light. Probably the pupil was generally supposed to react in accordance with the (subjective) brightness of the light entering through.