LIGHT GUIDE PLATE, SURFACE LIGHT SOURCE DEVICE, AND LIQUID CRYSTAL DISPLAY DEVICE
First Claim
1. A light guide plate comprising:
- a light guide plate main body including a first surface on which a light output from a light source section is made incident, a second surface adjacent to the first surface, a third surface which faces the first surface, and is adjacent to the second surface, and a fourth surface which faces the second surface, and is adjacent to the third surface;
a diffraction grating section arranged on the second surface;
wherein;
the diffraction grating section is configured in such a way that a plurality of gratings consisting of a dielectric is arranged in parallel at an interval Λ
along a predetermined direction facing from the first surface to the third surface;
whereinwhen a wavelength of a visible region possessed by the light is set to be λ
, the interval Λ
satisfies 1≧
Λ
/λ
0.5; and
whereinwhen a refraction index of the light guide plate main body is set to be ns, and a refraction index of the grating is set to be ng, the refraction index ng satisfies ng-ns≧
0.15.
1 Assignment
0 Petitions
Accused Products
Abstract
The present invention provides a light guide plate which can process in polarization separation, and emit a light in a desirable direction, a surface light source device, and a liquid crystal display device. A light guide plate 30 includes a light guide plate main body 31 including a first surface 31a on which a light 100 output from a light source section 20 is made incident, a second surface 31b adjacent to the first surface, a third surface 31d which faces the first surface, and is adjacent to the second surface, and a fourth surface which faces the second surface, and is adjacent to the third surface, and a diffraction grating section 32 arranged on the second surface 31b wherein; the diffraction grating section 32 is configured in such a way that a plurality of gratings 33 consisting of a dielectric is arranged in parallel at an interval Λ along a predetermined direction facing from the first surface to the third surface, wherein; when a wavelength of a visible region possessed by a light 100 is set to be λ, the interval Λ satisfies 1≧Λ/λ≧0.5, and when a refractive index of the light guide plate main body 31 is set to be ns, and a refractive index of the grating 33 is set to be ng, the refractive index ng satisfies ng-ns≧0.15.
86 Citations
9 Claims
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1. A light guide plate comprising:
-
a light guide plate main body including a first surface on which a light output from a light source section is made incident, a second surface adjacent to the first surface, a third surface which faces the first surface, and is adjacent to the second surface, and a fourth surface which faces the second surface, and is adjacent to the third surface; a diffraction grating section arranged on the second surface; wherein; the diffraction grating section is configured in such a way that a plurality of gratings consisting of a dielectric is arranged in parallel at an interval Λ
along a predetermined direction facing from the first surface to the third surface;
whereinwhen a wavelength of a visible region possessed by the light is set to be λ
, the interval Λ
satisfies 1≧
Λ
/λ
0.5; and
whereinwhen a refraction index of the light guide plate main body is set to be ns, and a refraction index of the grating is set to be ng, the refraction index ng satisfies ng-ns≧
0.15.- View Dependent Claims (2, 3, 4)
-
-
5. A surface light source device comprising:
-
a light source section outputting a light including the visible region; a light guide plate main body having a first surface on which the light output from the light source section is made incident, a second surface adjacent to the first surface, a third surface which faces the first surface, and is adjacent to the second surface, and a fourth surface which faces the second surface, and is adjacent to the third surface; a light guide plate including a diffraction grating section arranged on the second surface wherein; the diffraction grating section is configured in such a way that a plurality of gratings consisting of a dielectric is arranged in parallel at an interval Λ
along a predetermined direction facing from the first surface to the third surface wherein;when a wavelength of the visible region possessed by the light is set to be λ
, the interval Λ
satisfies 1≧
Λ
/λ
v0.5; and
whereinwhen a refraction index of the light guide plate main body is set to be ns, and a refraction index of the grating is set to be ng, the refraction index ng satisfies ng-ns≧
0.15. - View Dependent Claims (6, 7, 8)
-
-
9. A liquid crystal display device comprising:
-
a surface light source; a liquid crystal display section on which the light output from the surface light source device is made incident wherein; the surface light source including; a light source section outputting the light having the visible region; a light guide plate main body having a first surface on which the light output from the light source section is made incident, a second surface adjacent to the first surface, a third surface which faces the first surface, and is adjacent to the second surface, and a fourth surface which faces the second surface, and is adjacent to the third surface; a light guide plate having a diffraction grating section arranged on the second surface and wherein; the diffraction grating section is configured in such a way that a plurality of gratings consisting of a dielectric is arranged in parallel at an interval Λ
along a predetermined direction facing from the first surface to the third surface wherein;when a wavelength of the visible region possessed by the light is set to be λ
, the interval Λ
satisfies 1≧
Λ
/λ
0.5; and
whereinwhen a refraction index of the light guide plate main body is set to be ns, and a refraction index of the grating is set to be ng, the refraction index ng satisfies ng-ns≧
0.15.
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Specification
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- Resources
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Current AssigneeSumitomo Chemical Company Limited
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Original AssigneeSumitomo Chemical Company Limited
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InventorsKubota, Masaaki, Kim, Kiman
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Application NumberUS12/269,944Publication NumberTime in Patent OfficeDaysField of SearchUS Class Current362/606CPC Class CodesG02B 6/0035 provided on the surface of ...
