Dual display liquid crystal display device with particular CLC film between polarizers

1. A dual display liquid crystal display (LCD) device comprising:

a front light unit supplying light;

a first polarizer on the front light unit;

an LCD panel on the first polarizer;

only one selective reflection/transmission part on the LCD panel that includes a cholesteric liquid crystal (CLC) film that selectively transmits light having a first circular polarization and reflects light having a second circular polarization, wherein the first and second circular polarizations have opposite directions; and

a second polarizer on the selective reflection/transmission part:

wherein the selective reflection/transmission part selectively reflects the light in a reflection mode to display an image on a front side thereof in a first display mode;

wherein the selective reflection/transmission part passes the light in a transmission mode to display an image on a rear side thereof in a second display mode;

wherein the only one selective reflection/transmission part is between the first and second polarizer;

wherein the first and second optical axes of the first and second polarizers are substantially perpendicular to each other; and

wherein the LCD panel is between the only one selective/transmission part and the front light unit.

2. The dual display LCD device of claim 1 , wherein the front light unit has a light source at a side thereof.

3. The dual display LCD device of claim 1 , wherein the selective reflection/transmission part further comprises:

a first phase compensation film at the front of the CLC film that generates a phase difference of about λ/4 with respect to the light; and

a second phase compensation film at the rear of the CLC film, for generating a phase difference of λ/4 with respect to the light.

4. The dual display LCD device of claim 3 , wherein the first phase compensation film and the second phase compensation film are composed of a quarter wave plate (QWP).

5. The dual display LCD device of claim 3 , wherein an angle between the optical axes of the first phase compensation film and the second phase compensation film is about 90°.

6. A mobile communication device comprising:

a dual display liquid crystal display (LCD) device including:

a front light unit supplying light;

a first polarizer on the front light unit;

an LCD panel on the first polarizer;

only one selective reflection/transmission part on the LCD panel that includes a cholesteric liquid crystal (CLC) film that selectively transmits light having a first circular polarization and reflects light having a second circular polarization, wherein the first and second circular polarizations have opposite directions; and

a second polarizer on the selective reflection/transmission part;

wherein the selective reflection/transmission part selectively reflects the light in a reflection mode to display an image on a front side thereof in a first display mode; and

wherein the selective reflection/transmission part passes the light in a transmission mode to display an image on a rear side thereof in a second display mode;

communication means for communicating with an external side; and

a controller that controls the dual display LCD device and the communication means and controls on which side an image will be displayed;

wherein the only one selective reflection/transmission part is between the first and second polarizer;

wherein the first and second optical axes of the first and second polarizers are substantially perpendicular to each other; and

wherein the LCD panel is between the only one selective/transmission part and the front light unit.

7. The mobile communication device of claim 6 , wherein the selective reflection/transmission part further comprises:

a first phase compensation film at the front of the CLC film that generates a phase difference of about λ/4 with respect to the light; and

a second phase compensation film at the rear of the CLC film, for generating a phase difference of λ/4 with respect to the light.