Modulator for stereoscopic image device and stereoscopic image device using same

1. A modulator for a stereoscopic image device comprising:

a first substrate and a second substrate spaced apart from the first substrate;

first and second electrodes provided between the first substrate and the second substrate; and

a liquid crystal part provided between the first electrode and the second electrode wherein one or more of the first electrode or the second electrode is divided into a plurality of electrodes so as to apply a plurality of different voltages and the plurality of electrodes are insulated from one another;

wherein the applied voltage is controlled to gradually increase from a center part to an outer part of the first electrode or the second electrode.

2. The modulator according to claim 1 , wherein phase retardation of light transmitted through the liquid crystal part is controlled to gradually decrease from a center part to an outer part of the liquid crystal part.

3. The modulator according to claim 1 , wherein:

the first electrode or the second electrode includes a center electrode and outer electrodes spaced apart from the center electrode and provided outside the center electrode, and

the center electrode and the outer electrodes are arranged to be insulated from each other.

4. The modulator according to claim 3 , wherein:

the outer electrodes include a plurality of outer electrodes spaced apart from one another, and

the outer electrodes are arranged to be insulated from one another.

5. The modulator according to claim 3 , wherein voltages applied to the outer electrodes are controlled to be higher than a voltage applied to the center electrode.

6. The modulator according to claim 3 , wherein:

the outer electrodes are symmetrical with reference to the center electrode, and

the same voltage is applied to the outer electrodes separated from the center electrode by the same distance.

7. The modulator according to claim 1 , wherein, when different voltages are applied to the first electrode or the second electrode,

as a liquid crystal pattern formed in the liquid crystal part, different patterns are formed in correspondence with portions to which different voltages are applied, and

phase retardation occurring in a liquid crystal pattern corresponding to an electrode portion to which a relatively high voltage is applied is less than that occurring in a liquid crystal pattern corresponding to an electrode portion to which a relatively low voltage is applied.

8. A stereoscopic image device comprising:

a projector for projecting a stereoscopic image; and

a modulator for modulating the stereoscopic image projected by the projector into circularly polarized light in a clockwise or counterclockwise direction based on a signal linked with the projector,

wherein the modulator includes a first electrode, a second electrode and a liquid crystal part provided between the first and second electrodes, and

wherein one or more of the first electrode or the second electrode is divided into a plurality of electrodes so as to apply a plurality of different voltages and the plurality of electrodes are insulated from each other;

wherein the applied voltage is controlled to gradually increase from a center part to an outer part of the first electrode or the second electrode.

9. The stereoscopic image device according to claim 8 , wherein phase retardation of light transmitted through the liquid crystal part is controlled to gradually decrease from a center part to an outer part of the liquid crystal part.

10. The stereoscopic image device according to claim 8 , further comprising a beam splitter for transmitting light having a first polarization direction and reflecting light having a second polarization direction among lights radiated from the projector.

11. The stereoscopic image device according to claim 10 , further comprising:

a plurality of unit prisms adhered to each other in the vicinity of the beam splitter to pass light input to the beam splitter and light transmitted or reflected by the beam splitter; and

a substrate for guiding incident light to the plurality of unit prisms in order to prevent light energy loss due to a tolerance occurring upon arranging the plurality of unit prisms in the vicinity of the beam splitter.

12. The stereoscopic image device according to claim 10 , further comprising a prism for refracting and reflecting the light reflected by the beam splitter and radiating the light toward a screen

wherein an angle of incidence of the light reflected by the beam splitter to a reflection surface of the prism is equal to or greater than a critical angle for totally reflecting the light reflected by the beam splitter toward the screen.

13. A modulator for a stereoscopic image device comprising:

a first substrate and a second substrate spaced apart from the first substrate;

first and second electrodes provided between the first substrate and the second substrate; and

a liquid crystal part provided between the first electrode and the second electrode wherein one or more of the first electrode or the second electrode is divided into a plurality of electrodes so as to apply a plurality of different voltages to reduce phase retardation of polarized light and the plurality of electrodes are insulated from one another.

14. A stereoscopic image device comprising:

a projector for projecting a stereoscopic image; and

a modulator for modulating the stereoscopic image projected by the projector into circularly polarized light in a clockwise or counterclockwise direction based on a signal linked with the projector,

wherein the modulator includes a first electrode, a second electrode and a liquid crystal part provided between the first and second electrodes, and

wherein one or more of the first electrode or the second electrode is divided into a plurality of electrodes so as to apply a plurality of different voltages to reduce phase retardation of polarized light and the plurality of electrodes are insulated from each other.