Abstract: A lens module includes a first lens having positive refractive power, a second lens having positive refractive power, a third lens having negative refractive power, a fourth lens having positive refractive power, a fifth lens having positive or negative refractive power, and a sixth lens having negative refractive power. One or more inflection points may be formed on an image-side surface of the sixth lens.

Abstract: An optical imaging system includes first through seventh lenses. The first lens includes positive refractive power, the second lens includes a positive refractive power, the third lens includes a negative refractive power, an object-side surface thereof being convex, the fourth lens includes a positive refractive power, the fifth lens includes a negative refractive power, the sixth lens includes a negative refractive power, and the seventh lens includes a negative refractive power and having an inflection point formed on an image-side surface thereof. The first to seventh lenses are sequentially disposed from an object side toward an imaging plane.

Abstract: A lens module includes a first lens having refractive power, a second lens having refractive power, a third lens having refractive power, a fourth lens having refractive power, a fifth lens having refractive power and having a concave object-side surface and a concave image-side surface, and a sixth lens having refractive power and a concave image-side surface. The first to sixth lenses are sequentially disposed from an object side to an image side.

Abstract: An optical system includes a first lens including a negative refractive power, a second lens, a third lens, a fourth lens, and a fifth lens including a positive refractive power and an image-side surface being concave in a paraxial region. The first to fifth lenses are sequentially disposed from an object side to an image side.

Abstract: A hybrid cord for a tire, a method of manufacturing the same, and a high-performance environment-friendly radial tire including the same are disclosed herein. The hybrid cord includes a high-modulus fiber ply and a low-modulus fiber ply. The hybrid cord has a stress-strain curve including an initial modulus section, an intermediate modulus section and a final modulus section. The initial modulus of the initial modulus section is higher than the intermediate modulus of the intermediate modulus section, and the final modulus of the final modulus section is higher than the intermediate modulus.

Abstract: An optical imaging system includes first through seventh lenses. The first lens includes positive refractive power, the second lens includes a positive refractive power, the third lens includes a negative refractive power, an object-side surface thereof being convex, the fourth lens includes a positive refractive power, the fifth lens includes a negative refractive power, the sixth lens includes a negative refractive power, and the seventh lens includes a negative refractive power and having an inflection point formed on an image-side surface thereof. The first to seventh lenses are sequentially disposed from an object side toward an imaging plane.

Abstract: The present invention relates to a high resolution optical system. The optical system of the present invention includes, sequentially from an object side, a first lens having a positive refractive power and an object-side surface convex toward the object side; a second lens having a negative refractive power and an upwardly concave upper surface; a third lens having a positive refractive power; a fourth lens having a negative refractive power; a fifth lens having a positive refractive power and an upwardly convex upper surface; and a six lens having a negative refractive power and an upwardly concave upper surface.

Abstract: An optical imaging system includes a first lens having a concave image-side surface, a second lens having a concave image-side surface, and a third lens having a positive refractive power. The optical imaging system includes a fourth lens having a positive refractive power and a concave object-side surface, a fifth lens, a sixth lens having a positive refractive power, and a seventh lens having a concave object-side surface. The first lens to the seventh lens are sequentially disposed at intervals from an object side toward an imaging plane.

Abstract: The present invention relates to a high resolution optical system. The optical system of the present invention includes, sequentially from an object side, a first lens having a positive refractive power and an object-side surface convex toward the object side; a second lens having a negative refractive power and an upwardly concave upper surface; a third lens having a positive refractive power; a fourth lens having a negative refractive power; a fifth lens having a positive refractive power and an upwardly convex upper surface; and a six lens having a negative refractive power and an upwardly concave upper surface.

Abstract: An optical imaging system includes lenses sequentially disposed from an object side toward an imaging plane. A third lens, a fourth lens, and a fifth lens of the lenses each have a negative refractive power. An F number of the optical imaging system is 1.7 or less.

Abstract: A lens module may include a first lens having positive refractive power, a second lens having positive refractive power, a third lens having refractive power, a fourth lens having positive refractive power, a fifth lens having negative refractive power, and a sixth lens having negative refractive power and having one or more inflection points formed on an image-side surface thereof. An overall focal length of the lens module f and a focal length of the first lens f1 may satisfy the following Conditional Expression: 1.0<f1/f<2.0??[Conditional Expression].

Abstract: An optical imaging system includes a first lens having a positive refractive power, an image-side surface of the first lens being concave, a second lens, a third lens, an image-side surface of the third lens being concave, a fourth lens, a fifth lens, an image-side surface of the fifth lens being concave, and a sixth lens having a positive refractive power and having an inflection point formed on an image-side surface, wherein an F number of the optical imaging system is lower than 2.2.

Abstract: An optical imaging system includes first through seventh lenses. The first lens includes positive refractive power, the second lens includes a positive refractive power, the third lens includes a negative refractive power, an object-side surface thereof being convex, the fourth lens includes a positive refractive power, the fifth lens includes a negative refractive power, the sixth lens includes a negative refractive power, and the seventh lens includes a negative refractive power and having an inflection point formed on an image-side surface thereof. The first to seventh lenses are sequentially disposed from an object side toward an imaging plane.

Abstract: There is provided a lens module including: a first lens having positive refractive power; a second lens having negative refractive power; a third lens having positive refractive power; a fourth lens having negative refractive power and having a convex image-side surface; a fifth lens having negative refractive power; and a sixth lens having negative refractive power and having one or more inflection point on an image-side surface thereof.

Abstract: An optical imaging system includes a first lens having a negative refractive power, a convex object-side surface and a concave image-side surface; a second lens having a positive refractive power; a third lens having a negative refractive power; a fourth lens having a positive refractive power; a fifth lens having a negative refractive power; and a sixth lens having a positive refractive power. An image-side surface of the sixth lens has an inflection point. The first through sixth lenses are disposed sequentially from an object-side toward an imaging plane.

Abstract: Provided are a rubber composition for tire tread containing 100 parts by weight of raw material rubber, 10 parts to 100 parts by weight of a reinforcing filler, and 1 part to 20 parts by weight of a silane compound represented by the following formula (1), the raw material rubber containing 40 parts to 90 parts by weight of a styrene-butadiene rubber and 10 parts to 60 parts by weight of a butadiene rubber; and a tire produced using the rubber composition. The rubber composition for tire tread exhibit improved dispersibility, processability, mechanical characteristics, abrasion resistance performance, and rolling resistance characteristics. wherein X represents a vinyl group; Y represents an alkoxy group; Z represents an alkoxy group; a represents an integer from 0 to 6; b and c each independently represent an integer from 0 to 2 and do not necessarily represent 0 at the same time; and x represents an integer from 1 to 3.

Abstract: Disclosed is a tire-reinforcing steel cord for a radial tire. The tire-reinforcing steel cord has a double layer structure including a first-layer core and a second-layer core provided on the surface of the first-layer core. The first-layer core has an elliptical or rectangular cross section. The tire-reinforcing steel cord can improve processability, fatigue characteristics, and rolling resistance performance of a tire, resulting in improved fuel efficiency. A radial tire using the tire-reinforcing steel cord is also disclosed.

Abstract: An optical system includes a first lens including a negative refractive power and a convex object-side surface, a second lens, and a third lens including a negative refractive power and a convex object-side surface. The optical system also includes a fourth lens, a fifth lens including a negative refractive power, and a sixth lens including a negative refractive power and comprising an inflection point on an image-side surface thereof. The first to sixth lenses are sequentially disposed from an object toward an imaging plane.

Abstract: An optical system includes a first lens including a positive refractive power, a second lens including a positive refractive power and a convex image-side surface, a third lens, and a fourth lens. The optical system includes a fifth lens including a concave object-side surface and a concave image-side surface, and a sixth lens including an inflection point formed on an image-side surface thereof. The first to sixth lenses are sequentially disposed from an object toward an imaging plane.

Abstract: The present invention relates to an optical system. An optical system of the present invention includes, sequentially from an object side, a first lens having a positive refractive power and an object-side surface convex toward the object side; a second lens having a negative refractive power; a third lens having a negative refractive power; a fourth lens having a positive refractive power, a fifth lens having a negative refractive power and an image-side surface convex toward an image side; and a sixth lens having a negative refractive power and an image-side surface concave toward the image side.