Optical waveguides – Optical fiber waveguide with cladding
Patent
1993-05-25
1996-07-30
Healy, Brian
Optical waveguides
Optical fiber waveguide with cladding
385901, 385129, 385143, 385146, 362 31, 362 33, G02B 610
Patent
active
055420176
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention relates to a light scattering light guide, which is capable of radiating scattered light around while guiding light, its manufacturing method and applied optical apparatuses or devices which employ the light scattering light guide.
More particularly, this invention relates to a light scattering light guide, which is capable of converting an incoming light flux having a relatively small cross-sectional area into an outgoing light flux having a relatively large area with high efficiency and uniformity by utilizing an irregular structure produced in the process of polymerization of organic materials, its manufacturing method, and applied optical apparatuses or devices such as light source apparatuses, lighting apparatuses, and light branching apparatuses, which make effective use of the characteristics of the light scattering light guide.
BACKGROUND ART
Conventionally, various types of optical elements or apparatuses, which are designed to guide and scatter incident light at the same time and let it out in multiple directions, have been publicly known.
One type of such known optical elements or apparatuses configures a surface type light source, in which light is allowed to come in through a side of an extending plate-shaped transparent material, with a reflecting element installed on one surface side, and the vicinity of the other surface provided with light diffusivity to obtain a light outgoing surface, thereby enabling the apparatus to be used as a backlight source or the like for a liquid crystal display.
This type includes, for example, those described in the Published Unexamined Japanese Patent Application No. 62-235905, the Published Unexamined Japanese Patent Application No. 63-63083, the Published Unexamined Japanese Patent Application No. 2-13925, and the Published Unexamined Japanese Patent Application No. 2-245787.
In surface type light sources employing those light scattering light guide apparatuses, light scattering is not volumetrically caused inside a transparent body; instead, the light is merely spread in a light outgoing direction by utilizing irregular reflection or mirror reflection in the vicinity of the surface of the transparent body or in a reflecting element, and so, it cannot necessarily be said that such light scattering light guide apparatus is capable of providing a high light diffusivity.
In addition, when an attempt is made to obtain a surface type light source, which receives light from a side and gives uniform illuminance, it is necessary to provide the reflectivity or the like of a reflecting element with some gradient as may be easily understood from the examples shown in the known documents mentioned above. This unavoidably results in a complicated and large (especially thick) structure of the light scattering light guide apparatus.
Accordingly, in using this type of light scattering light guide as the light source or the like of a backlight for a liquid crystal display device, which is required to have a uniform and high illuminance and a thin structure, various additional configuring means are necessary to reinforce light scattering and assure uniform illuminance for a surface type light source. Incorporating such light scattering power reinforcing means, however, used to conflict with the requirement for a thin structure.
Another type of known optical elements or apparatuses has a light diffusing plate which consists of an extending plate-shaped transparent material with a granular substance dispersed therein, the granular substance having a different refraction index from that of the transparent material.
This type includes, for example, those disclosed in the Published Unexamined Japanese Patent Application No. 1-172801, the Published Unexamined Japanese Patent Application No. 1-236257, the Published Unexamined Japanese Patent Application No. 1-269901, the Published Unexamined Japanese Patent Application No. 1-269902, and Published Unexamined Japanese Patent Application No. 2-221925.
The aforesaid Published Unexamined Japanes
REFERENCES:
patent: 4294517 (1981-10-01), Jakubek
patent: 4925268 (1990-05-01), Iyer et al.
patent: 4989956 (1991-02-01), Wu et al.
patent: 5050946 (1991-09-01), Hathaway et al.
patent: 5113476 (1992-05-01), Okada et al.
patent: 5202950 (1993-04-01), Arego et al.
P. Debyr, et al., "Scattering by an Inhomogeneous Solid", Journal of Applied Physics, vol. 20, pp. 517-525, Jan. 1949, New York.
Y. Koike, et al., "Original of Excess Light Scattering in Poly(methyl methacrylate) Glasses", Macromolecules, vol. 22, pp. 1367-1373, Mar. 1989, New Jersey.
Y. Koike, et al., "Light Scattering and Heterogeneities in Low-Loss Poly(methyl Methacrylate) Glasses", Macromolecules, vol. 25, pp. 4807-4815, Mar. 1992, New Jersey.
Healy Brian
Ngo John
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