DUAL DISPLAY APPARATUS

1 . A dual display apparatus comprising:

two activable displays capable of displaying an image signal, wherein the two displays differ in display characteristics; and

means for activating one of the displays in accordance with properties of an image signal.

2 . The dual display device according to claim 1 , wherein:

the two displays are configured in a front-and-back-side relationship by integrating the two displays so as to have each display surface of the two displays placed on an outer side.

3 . The dual display apparatus according to claim 1 , wherein:

one of the displays is used for displaying an image signal representing a natural image, while the other of the displays is used for displaying a computer image.

4 . The dual display apparatus according to claim 1 , wherein:

one of the displays is an organic EL display, while the other of the displays is a liquid crystal display.

5 . The dual display apparatus according to claim 4 , including a main body section wherein:

the displays are foldably attached to the main body section providing an operating unit having a plurality of buttons on one surface of the main body section;

means responsive when the dual display apparatus is unfolded to enable operation of the operating unit, the liquid crystal display is situated on an operating unit side, and activated, and

when the dual display apparatus is folded to cover the operating unit, the organic EL display is situated on the outer side of the dual display apparatus, and activated.

6 . The dual display apparatus according to claim 4 , wherein:

a menu screen of the organic EL display is configured as a screen that has a greater black area and a lower brightness compared with those of a menu screen for the liquid crystal display.

7 . The dual display apparatus according to claim 1 , wherein:

the one of the displays differs in resolution from the other of the displays.

8 . The dual display apparatus according to claim 1 , wherein:

the one of the displays differs in a subpixel structure for forming color pixels from the other of the displays.

9 . The dual display apparatus according to claim 1 , wherein:

the one of the displays is of a delta array type, while the other of the displays is of a stripe array type.

10 . A dual display apparatus comprising:

two displays capable of displaying the same signal, wherein:

pixels in the two displays are usable as a memory for storing display data; and

while one of the two displays is being used for displaying data, the pixel in the other of the two displays is used as the memory for storing display data.

11 . The dual display apparatus according to claim 10 , wherein:

the two displays are organic EL displays.

12 . The dual display apparatus according to claim 11 , wherein:

a static memory is installed in each pixel of the organic EL displays.

13 . The dual display apparatus according to claim 11 , wherein:

in the pixels of the organic EL displays, RGB pixels of one of the organic EL displays are respectively composed of different organic EL materials, while the RGB pixels of the other of the organic EL displays are formed of a white organic EL material and a color filter.

14 . The dual display apparatus according to claim 11 , wherein:

a sealing substrate is shared by both of the organic EL displays.

15 . The dual display apparatus according to claim 10 , wherein:

means for driving the pixel usable as the memory at a voltage different from that applied at the time of displaying data while the pixel is being used as a part of the memory for the display data.