Abstract: Visual recognition testing apparatus is described which has a master array of individually selectable areas to be illuminated and a slave array of individual areas to be illuminated. A test sheet can be superimposed in front of the two arrays so as to show two sets of the same shapes differently arranged. The apparatus provides a controlled sequence of illumination of the shapes of a master array one after the other in response to correct choosing of corresponding shapes in the slave set of shapes by means of illumination of a chosen area of the slave array. A pupil controls illumination of the areas of the slave array and selection of a matching shape by settling on a chosen area of the slave array by the use of one or two switches.

Abstract: To enable a severely disabled person to use an electric typewriter for arithmetic calculations an electronic calculator is coupled to the printing mechanism of the typewriter through a selector whereby the transmission of the output of the calculator to the printing mechanism can be permitted or prevented. To simulate the key-signals normally used for the calculator, a simulator circuit is coupled to the control apparatus provided for enabling a disabled person to use the typewriter and simulates key-signals in response to commands from such control apparatus. One or more infrequently used signals from the control apparatus are employed as special signals to operate the selector to permit print-out of the calculator output when required.