A set of equations is introduced which describes the inhibitory interaction between the receptors in the eye of the horse-shoe crab, Limulus. The terms primary inhibition field, and inhibition field are defined, and the results of a digital computer study of their interdependence with respect to size and to the type of k[subscript i,j] and t[subscript i,j] functions employed are given. It is concluded that a large receptor array can be simulated by solving the set of equations for the output of the central receptor in much smaller sub-arrays. If the sub-arrays are chosen so as to cover the large array, then the resulting set of central receptor outputs provides a good approximation to the output of the large array. A device which simulates a large receptor array by repetitive solution of the set of equations for 9×9 sub-arrays is described. Various switching arrangements which reduce the complexity of the device are detailed. The circuit diagrams for all the required elements are given. In order to evaluate the possible utility of the device as a tool in pattern recognition studies, the output from the device for certain simple patterns was simulated on the digital computer. The results of this study are given, and some possible applications to the field of pattern recognition are mentioned. It is pointed out that the design of the device makes it a versatile instrument for simulating various types of receptor arrays. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate