The method of measurement and analyse of the pupil response to the light

The analyse of the shape, size and reactivity of the human eye's pupil is a very valuable diagnostic method which is used mainly to evaluate condition of the autonomic nervous system. This paper presents a experimental set-up, which enables to record and analyse the time characteristics of the pupil reactivity during pupil response to the light (Pupil Light Reflex - PLR). The system was designed, build and tested in the Institute of Physics of the Wroclaw University of Technology. The obtaining of reliable PLR depends on stimulation and measurement conditions. The proposed system permits an accurate determination of the time characteristics of the PLR dynamic response and easy and fast quantitative methods for determination of the PLR parameteres. The system of two linear sensors is used as the detection element. It allows to record and digitize the pupil diameter at the rate of 90 times/second, with the accuracy of 0.05 mm. The parametres of the light stimulation in the form of a single and periodic light pulses are adjustable. The examples of the experimental results showing PLR characteristics in selected ophthalmic pathologies are presented.