Sight controllable display device and terminal having the same

Abstract

To provide a sight controllable display device that is capable of switching a regular display and a concealed display easily. A display panel and a modulator are disposed between two polarizing plates. The display panel performs a regular display drive. Meanwhile, the modulator drives to operate at a speed faster than twice the speed of the display panel and modulate the display image of the display panel. When displaying an image that is desired to be concealed, the period where the modulator is not in action is selected and viewed by a shutter. By stopping the action of the modulator, the regular display can be viewed as it is without the shutter.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view for showing a first embodiment of a display device according to the present invention;

FIG. 2 is a graph for showing a transmittance characteristic of the case where a normally-white liquid crystal element and a normally-off modulator are combined;

FIG. 3 is a time chart for showing a first example of the display action of the first embodiment;

FIG. 4 is a time chart for showing a second example of the display action of the first embodiment;

FIG. 5 is a schematic cross section for showing a second embodiment of the display device according to the present invention;

FIG. 6 is a schematic cross section for showing a third embodiment of the display device according to the present invention;

FIG. 7 is a schematic model illustration for showing a fourth embodiment of the display device according to the present invention;

FIG. 8 is a schematic cross section for showing a specific structural example (first example) that embodies the fourth embodiment;

FIG. 9 is a schematic cross section for showing a specific structural example (second example) that embodies the fourth embodiment;

FIG. 10 is a timing chart for showing the display action (first example) of a sixth embodiment of the display device according to the present invention;

FIG. 11 is a timing chart for showing the display action (second example) of the sixth embodiment of the display device according to the present invention;

FIG. 12 is a schematic cross section for showing a seventh embodiment of the display device according to the present invention;

FIG. 13 is a schematic perspective view for showing the seventh embodiment of the display device according to the present invention;

FIG. 14 is a perspective view for showing an embodiment of a terminal according to the present invention;

FIG. 15 is a perspective view for showing a conventional technique disclosed in Patent Document 1;

FIG. 16 is a cross section for showing a conventional technique disclosed in Patent Document 2; and

FIG. 17 is a perspective view for showing a conventional technique disclosed in Patent Document 3.

Claims

1. A sight controllable display device, comprising two polarizing plates, a display panel provided between the two polarizing plates, a modulator provided between the display panel and either one of the two polarizing plates, and an observing shutter, wherein:the display panel forms an image by changing transmittance of light that transmits through the two polarizing plates;the modulator repeats an inversion mode for inverting the image formed on the display panel and a non-inversion mode for not inverting the image; andthe observing shutter is for observing the display panel, which repeats a translucent mode for transmitting light and a shielding mode for not transmitting the light in connection with an action of the modulator.

2. The sight controllable display device as claimed in claim 1, wherein the observing shutter turns to the shielding mode when the modulator is in the inversion mode and turns to the translucent mode when the modulator is in the non-inversion mode.

3. The sight controllable display device as claimed in claim 1, wherein the modulator repeats the inversion mode and the non-inversion mode by modulating a birefringence amount or optical rotation property, which is added to light transmitting the display panel or light that has transmitted the display panel.

4. The sight controllable display device as claimed in claim 1, wherein the modulator repeats the inversion mode and the non-inversion mode by modulating a depolarization characteristic that is added to light transmitting the display panel or light that has transmitted the display panel.

5. The sight controllable display device as claimed in claim 4, wherein the modulator is constituted with a compound of a liquid crystal and a polymer.

6. The sight controllable display device as claimed in claim 1, wherein the modulator is divided into a plurality of segments, and repeats the inversion mode and the non-inversion mode for each of the segments.

7. The sight controllable display device as claimed in claim 1, wherein the modulator repeats the inversion mode and the non-inversion mode in accordance with a sequence of two values or more.

8. A terminal, comprising the sight controllable display device as claimed in claim 1.