摘要 |
An interactive display device, of the type which displays data and allows an operator to input fresh data and/or change the data which is displayed, comprises a modular display panel (4) which contains display modules (6) providing arrays of discrete display elements, each element being independently driven to produce an optical output. A light pen detects light when pointed at the display element associated with the data to which a desired input relates. The arrays are scanned simultaneously with signals which determine whether each display element is in the ON or OFF state, the scanning signals including coded pulses representative of the particular array being scanned. Data is input by means of the light pen, which plugs into a socket (11) at the front of the unit, and associated circuit means operative to identify the coded pulses and thus identify the array containing a selected display element. <IMAGE> |