an input data display device makes it easier to input properly correlated relative corrections for a number of parameters . relative amounts by which each of a number of parameters is to be adjusted can be displayed on the screen in a manner which shows their ranges and possible correlation . the data are input when the operator touches spots which he selects on the display screen . the pressure of his finger causes data to be generated which represent those input positions . a calculation device calculates output - ready relative correction values for the various parameters based on these input position data . these values are transmitted to the connected device .