Image display device, electronic apparatuse using the same, display output control method for image display device, and output control program thereof

Abstract

Provided is a display device having a viewing angle changing function, which is capable of preventing leakage of information displayed on a display screen even when there is a fault generated in changing the viewing angle. The image display device including a viewing angle changing element capable of changing a wide vision display and a narrow vision display and including a display element is provided with a detection element which detects a fault generated in the viewing angle changing element and a module for changing to a narrow vision display when there is a fault based on a detection value of the detection element. For example, when there is a fault, a transparent heater is operated to heat a liquid crystal layer to set a transparent-scattering changing element to a transparent state and forcibly set the display device to a narrow vision display.

What is claimed is: 
     
         1 . An image display device, comprising a display device main body which includes a display element for displaying prescribed image information to outside and a viewing angle changing element for setting to change display of image information on the display element at least from a wide vision display to a narrow vision display based on a changing command from the outside, wherein:
 the display device main body is provided with an operation state detection element which detects an operation state of the viewing angle changing element;   the viewing angle changing element is provided with a narrow vision forcible setting module which operates to forcibly set the display of the display element to a narrow vision display state by a voltage forcible applying mechanism which applies a voltage to the viewing angle changing element, when the operation state detected by the operation state detection element is a fault state;   the operation state detection element is formed by an electric current detection element which measures an electric current flown in the viewing angle changing element; and the fault judging module which judges whether or not there is a fault generated in the viewing angle changing element based on an electric current detected value acquired by the electric current detection element is provided; and   the fault judging module comprises a storage section which stores desired electric current values flowing to the viewing angle changing element as reference electric current values, and compares the reference electric current values stored in the storage section with the electric current value detected by the electric current detection element to judge whether or not there is a fault generated in the viewing angle changing element.   
     
     
         2 . The image display device as claimed in  claim 1 , wherein
 the voltage forcible applying mechanism is formed by a pair of transparent electrodes covered by an insulating layer and insulated from a voltage applying electrode that is used under a normal state where no fault is generated.