To retain the high quality of a monitor screen without lowering workability by releasing a screen saver function at the time of detecting the event from a control part and at the time of detecting the event from the part other than the control part.
When the key input or the depressing of a screen saver releasing key or the like from a control part 4 are performed, an external event detecting means 3 requests the releasing of the screen saver releasing function of a screen control means 2 to return the screen of a monitor screen 1 to an original state. Moreover, an internal event detecting means 6 requests the releasing of the screen saver function to the means 2 by events of the error message from a device main body 5, etc., to return the monitor screen 1 to the original state. Thus, the screen layer saver function is automatically released when the operating of the device and the monitoring of the operation are needed in this manner and the screen saver function is executed only when the monitor screen is not needed.
NONAKA SATOSHI
AZUMA YASUHIRO
KURATA HIROAKI
