Abstract: A backlight unit includes a light source and a two-dimensional micro lens array (MLA) sheet including a plurality of lens unit each having a conic lens shape with a cross-section, taken through the lens axis, having a shape defined by the equation: y = x 2 / r 1 + 1 - ( 1 + k ) ? ( 1 / r ) 2 ? x 2 where k is a constant with a value of less than or equal to ?1, and r is the radius of curvature at the peak of the lens unit.

Abstract: The present invention relates to an optical film having improved optical performance and to a backlight unit comprising the same. More particularly, the present invention relates to a microlens array (MLA) sheet which comprises a base unit and a lens unit formed on one side of the base unit, wherein the lens unit consists of a plurality of conical lenses. Existing hemispherical microlens array sheets have limitations in terms of improving luminance, and therefore cannot replace prism sheets in high luminance product s. However, the microlens array sheet consisting of conical lenses of the present invention can improve both luminance and viewing angle characteristics.

Abstract: The present invention relates to a microlens array sheet with enhanced optical performance, and a backlight unit having same, and more specifically, to a microlens array sheet and a backlight unit having same, the microlens array sheet comprising: a base portion; and a plurality of microlenses formed on one surface of the base portion, wherein the plurality of microlenses have an irregular array, and the standard deviation of the distance between the mid points of two microlenses adjacent to each other is, 2-20% of the average pitch(p) between microlenses adjacent from the mid point of a selected microlens after selecting one of the microlenses.

Abstract: Provided is a backlight unit. The backlight unit includes a light source, an optical member configured to uniformly distribute light emitted from the light source, and at least two condensing films configured to condense light from the optical member. Hetero-conic lenses are two-dimensionally arranged on a surface of each of the condensing films, and each of the hetero-conic lenses is formed by combining a first conic lens expressed by Formula (1) below and a second conic lens expressed by Formula (2) below: y = H 1 - x 2 / r 1 1 + 1 - ( 1 + k 1 ) ? ( 1 / r 1 ) 2 ? x 2 ? ? ( 0 ? y ? y 0 ) Formula ? ? ( 1 ) y = H 2 - x 2 / r 2 1 + 1 - ( 1 + k 2 ) ? ( 1 / r 2 ) 2 ? x 2 + y 0 ? ? ( y 0 ? y ? H 2 ) .

Abstract: There are provided a micro lens array (MLA) sheet including a plurality of lens units two-dimensionally arranged thereon, wherein each lens unit has a conic lens shape of which a vertical cross-section taken in a lens center is represented by Expression 1, and a backlight unit including the same.

Abstract: A light extraction member includes a plurality of unit lenses arranged on one surface thereof. Each of the unit lenses comprises a combination of two or more kinds of conic lenses.

Abstract: The present invention relates to a microlens array sheet with enhanced optical performance, and a backlight unit having same, and more specifically, to a microlens array sheet and a backlight unit having same, the microlens array sheet comprising: a base portion; and a plurality of microlenses formed on one surface of the base portion, wherein the plurality of microlenses have an irregular array, and the standard deviation of the distance between the mid points of two microlenses adjacent to each other is, 2-20% of the average pitch(p) between microlenses adjacent from the mid point of a selected microlens after selecting one of the microlenses.

Abstract: The present invention relates to an optical film having improved optical performance and to a backlight unit comprising the same. More particularly, the present invention relates to a microlens array (MLA) sheet which comprises a base unit and a lens unit formed on one side of the base unit, wherein the lens unit consists of a plurality of conical lenses. Existing hemispherical microlens array sheets have limitations in terms of improving luminance, and therefore cannot replace prism sheets in high luminance products. However, the microlens array sheet consisting of conical lenses of the present invention can improve both luminance and viewing angle characteristics.

Abstract: Disclosed is a method of fabricating an optical fiber or an optical device doped with reduced metal ion and/or rare earth ion, comprising steps of: forming a partially-sintered fine structure in a base material for fabricating the optical fiber or the optical device; soaking the fine structure into a doping solution containing a reducing agent together with metal ion and rare earth ion during a selected time; drying the fine structure in which the metal ion and/or rare ion are/is soaked; and heating the fine structure such that the fine structure is sintered.

Abstract: Provided is a backlight unit. The backlight unit includes a light source, an optical member configured to uniformly distribute light emitted from the light source, and at least two condensing films configured to condense light from the optical member.

Abstract: A light extraction member includes a plurality of unit lenses arranged on one surface thereof. Each of the unit lenses comprises a combination of two or more kinds of conic lenses.

Abstract: There is provided a process of making a mold for optical films. The process of making a mold for optical films comprises: etching a stereostructure in a surface of the mold having a flat surface or an engraved convex and concave surface, by using a laser beam. The process of making a mold for optical films may be useful to easily mark spots, to control the height of protrusions and the position where the protrusions are formed, and also to form the protrusions having constant depths even in a curved surface such as a convex and concave surface.

Abstract: There is provided a process of making a mold for optical films. The process of making a mold for optical films comprises: etching a stereostructure in a surface of the mold having a flat surface or an engraved convex and concave surface, by using a laser beam. The process of making a mold for optical films may be useful to easily mark spots, to control the height of protrusions and the position where the protrusions are formed, and also to form the protrusions having constant depths even in a curved surface such as a convex and concave surface.

Abstract: The present invention relates to a method for manufacturing an optical fiber preform using an MCVD process comprising (A) forming a predetermined thickness of a cladding layer in a preform tube by repeating a unit process of heating an outer peripheral surface of the preform tube at 1,700 to 2,5000 C using a heat source moving in a process direction, and simultaneously injecting cladding layer forming gas and chlorine (Cl) gas into the preform tube; and (B) forming a predetermined thickness of a core layer in the preform tube by repeating a unit process of heating the outer peripheral surface of the preform tube at 1,700 to 2,5000 C using the heat source moving in a process direction, and simultaneously injecting core layer forming gas and chlorine (Cl) gas into the preform tube having the cladding layer.

Abstract: Disclosed is a method of fabricating an optical fiber or an optical device doped with d metal ion and/or rare earth ion, comprising steps of: forming a partially-sintered fine re in a base material for fabricating the optical fiber or the optical device; soaking the fine re into a doping solution containing a reducing agent together with metal ion and rare on during a selected time; drying the fine structure in which the metal ion and/or rare ion soaked; and heating the fine structure such that the fine structure is sintered.

Abstract: Disclosed is a method of fabricating an optical fiber or an optical device doped with reduced metal ion and/or rare earth ion, comprising steps of: forming a partially-sintered fine structure in a base material for fabricating the optical fiber or the optical device; soaking the fine structure into a doping solution containing a reducing agent together with metal ion and rare earth ion during a selected time; drying the fine structure in which the metal ion and/or rare ion are/is soaked; and heating the fine structure such that the fine structure is sintered.

Abstract: The present invention relates to a measurement method of resonant nonlinearity in a nonlinear optical fiber using a long period fiber grating pair. In particular, it relates to a characteristic evaluation method that can simply, but accurately, measure the nonlinear optical characteristics of an optical fiber.