Thin film type back light unit for flat panel display
First Claim
1. A flat panel display device having a display panel and a back light unit, the back light unit comprising:
- a base film having a width and a length and including a high refractive film and a low refractive film on the high refractive film;
a first incident pattern at a one side of a first surface of the base film;
a reflective pattern on the first surface of the base film at an opposite side from the one side having the first incident pattern, wherein a distance between the first incident pattern and the reflective pattern is substantially equal to the length of the first surface of the base film, and wherein a length of the reflective pattern is substantially equal to the width of the first surface of the base film;
a light radiating pattern on a second surface of the base film; and
a light source spaced apart from the first incident pattern with a first focal length and providing an incident light to the first incident pattern.
2 Assignments
0 Petitions
Accused Products
Abstract
Disclosed is a flat panel display device having a display panel and a back light unit in which the back light unit may, for example, include a base film having a width and a length and including a high refractive film and a low refractive film on the high refractive film; a first incident pattern at a one side of a first surface of the base film; a reflective pattern on the first surface of the base film at an opposite side spaced apart from the one side with a distance substantially corresponding to the length of the first surface of the base film and substantially covering the width of the first surface of the base film; a light radiating pattern on a second surface of the base film; and a light source spaced apart from the first incident pattern with a first focal length and providing an incident light to the first incident pattern.
6 Citations
9 Claims
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1. A flat panel display device having a display panel and a back light unit, the back light unit comprising:
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a base film having a width and a length and including a high refractive film and a low refractive film on the high refractive film; a first incident pattern at a one side of a first surface of the base film; a reflective pattern on the first surface of the base film at an opposite side from the one side having the first incident pattern, wherein a distance between the first incident pattern and the reflective pattern is substantially equal to the length of the first surface of the base film, and wherein a length of the reflective pattern is substantially equal to the width of the first surface of the base film; a light radiating pattern on a second surface of the base film; and a light source spaced apart from the first incident pattern with a first focal length and providing an incident light to the first incident pattern.
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2. The device according to the claim 1, further comprising:
a reflection layer covering the first surface of the base film excluding the incident pattern and the reflective pattern.
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3. The device according to the claim 1, wherein the first incident pattern includes a holography pattern that converts the incident light into an expanded light,
wherein the incident light perpendicularly enters onto a surface of the incident pattern, and wherein the expanded light has a refraction angle greater than a critical angle for total reflection at an interface between the high refractive film and the low refractive film, and is expanded substantially corresponding to the width.
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4. The device according to the claim 3, wherein the expanded light propagates to the reflective pattern through the high refractive film.
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5. The device according to the claim 4, wherein the reflective pattern includes a holography pattern that converts the expanded light into a collimated light which has a reflection angle smaller than the refraction angle and greater than a critical angle of total reflection at an interface between the low refraction film and an air, and covers the width.
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6. The device according to the claim 5, wherein a portion of the collimated light is refracted by the light radiating pattern in a substantially perpendicular direction to the second surface of the base film, and is radiated outward from the low refractive film.
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7. The device according to the claim 1, further comprising:
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a second incident pattern on the second surface of the base film, facing the first incident pattern, wherein the light source is spaced apart from the second incident pattern with a second focal length, and provides the incident light to the second incident pattern.
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8. The device according to the claim 7, wherein the first incident pattern is a holography pattern made with a short wavelength light of the incident light, and
wherein the second incident pattern is a holography pattern made with a long wavelength light of the incident light.
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9. The device according to the claim 7, wherein a distance difference between the first focal length and the second focal length substantially corresponds to a thickness of the base film.
Specification