Abstract: An optical imaging system includes a first lens group, a second lens group, a third lens group, and a fourth lens group sequentially disposed in ascending numerical order along an optical axis of the optical imaging system from an object side of the optical imaging system toward an image side of the optical imaging system, at least one lens group among the first lens group to the fourth lens group being configured to be movable along the optical axis; and a reflective member disposed on an object side of the first lens group and comprising a reflective surface configured to change an optical path, wherein the first lens group has a positive refractive power, and 0.8?Fnot/Fnow?1.3 is satisfied, where Fnot is an F-number of the optical imaging system in a telephoto mode, and Fnow is an F-number of the optical imaging system in a wide-angle mode.

Abstract: A four-lens optical system is provided which is capable of minimizing a total length of an optical system while having a high numerical aperture (NA), and, more particularly, to an optical system including a first lens, a second lens, a third lens, and a fourth lens that are sequentially arranged from an object side to an image side of the four-lens optical system, in which the first lens and the second lens continuously disposed in front of the optical system are each configured to have positive refractive power and in which the first lens is a lens is made of a plastic material, and the fourth lens is a lens made of a glass material.

Abstract: The present invention relates to a lens optical system including a first lens, a second lens, a third lens, a fourth lens, and a fifth lens that are sequentially arranged from an object side to an image side, in which the first lens has positive refractive power and the second lens has negative refractive power.

Abstract: An imaging lens system includes a first lens having a negative refractive power, a second lens having a refractive power, a third lens having a refractive power, a fourth lens having a refractive power, a fifth lens having a refractive power, and a sixth lens having a convex object-side surface is convex in a paraxial region thereof and a concave image-side surface in a paraxial region thereof. The first to sixth lenses are sequentially disposed in ascending numerical order along an optical axis of the imaging lens system from an object side of the imaging lens system toward an image plane of the imaging lens system, and one or more of the first to fifth lenses is configured to be movable in a direction of the optical axis.

Abstract: An optical imaging system includes a first lens group, a second lens group, a third lens group, and a fourth lens group sequentially disposed in ascending numerical order along an optical axis of the optical imaging system from an object side of the optical imaging system toward an imaging plane of the optical imaging system, wherein at least one lens group among the first lens group to the fourth lens group is configured to be movable along the optical axis, the first lens group has a positive refractive power and comprises a reflective member and at least one lens disposed between the object side of the optical imaging system and the reflective member, and the at least one lens is configured to refract light passing through the at least one lens to converge the light to be incident on the reflective member.

Abstract: An imaging lens system includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens, sequentially disposed from an object side. A field of view (FOV) of the imaging lens system according to an embodiment is wider than 85 degrees and narrower than 160 degrees. In the imaging lens system according to an embodiment, a distance (TTL) from an object-side surface of the first lens to an imaging plane is greater than 6.0 mm and less than 9.0 mm.

Abstract: A super wide angle zoom lens may include: a first lens having convex surfaces at an object side and an image side, and formed in a spherical shape; a second lens having a concave surface at the object side; a third lens having a convex surface at the image side; and a fourth lens having a convex surface at the object side and formed in a spherical shape, wherein the first to fourth lenses are sequentially arranged from the object side toward the image side.

Abstract: A super wide angle zoom lens may include: a first lens having convex surfaces at an object side and an image side, and formed in a spherical shape; a second lens having a concave surface at the object side; a third lens having a convex surface at the image side; and a fourth lens having a convex surface at the object side and formed in a spherical shape, wherein the first to fourth lenses are sequentially arranged from the object side toward the image side.

Abstract: Provided are a telephoto zoom lens system and an electronic apparatus including the telephoto zoom lens system. The telephoto zoom lens system includes a first lens group having a positive refractive power and is fixed when zooming and focusing, a second lens group having a negative refractive power, a third lens group having a negative refractive power and performs focusing, a fourth lens group having a positive refractive power, and a rear lens group comprising one or more lens groups located between the fourth lens group and an image side. At least one lens group of the rear lens group is fixed while zooming, and a focal length thereof is unchanged while zooming.

Abstract: A reflective type telephoto lens and a photographing apparatus including the reflective type telephoto lens are provided. The reflective type telephoto lens includes: a first lens that receives an incident flux of light from an object side; a main mirror including a reflective unit that reflects light transmitted through the first lens toward the object side, and a transmission portion disposed on a center portion thereof; a sub-mirror group including a sub-mirror that reflects light from the main mirror toward an image side; and a focusing lens group that focuses the light reflected by the sub-mirror.

Abstract: A telephoto lens system and an electronic apparatus having the same are provided. The telephoto lens system includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group. The third lens group includes a (3-1)-th lens group having a positive refractive power, a (3-2)-th lens group having a negative refractive power, and a (3-3)-th lens group having a positive refractive power.

Abstract: A telephoto lens system and an electronic apparatus having the same are provided. The telephoto lens system includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group. The third lens group includes a (3-1)-th lens group having a positive refractive power, a (3-2)-th lens group having a negative refractive power, and a (3-3)-th lens group having a positive refractive power.

Abstract: Provided are a telephoto zoom lens system and an electronic apparatus including the telephoto zoom lens system. The telephoto zoom lens system includes a first lens group having a positive refractive power and is fixed when zooming and focusing, a second lens group having a negative refractive power, a third lens group having a negative refractive power and performs focusing, a fourth lens group having a positive refractive power, and a rear lens group comprising one or more lens groups located between the fourth lens group and an image side. At least one lens group of the rear lens group is fixed while zooming, and a focal length thereof is unchanged while zooming.

Abstract: A telephoto zoom lens system includes a first lens group having a positive focal length, a second lens group having a negative focal length, a third lens group having a positive or negative focal length, a fourth lens group having a positive focal length, and a fifth lens group for performing hand shake compensation by allowing a portion of the fifth lens group to move perpendicularly to the optical axis. During zooming, the first and fifth lens groups are fixed and the second, third, and fourth lens groups move, and the third or fourth lens group is a focusing lens group.

Abstract: Provided are a macro lens system and an image pickup device including the macro lens system. The macro lens system includes a first lens group having a positive refractive power, a second lens group having a positive refractive power, and a 3-1 lens group having a positive refractive power and moving perpendicular to an optical axis to correct an image blur.

Abstract: A macro lens system and a pickup device that includes the macro lens system include, in order from an object side to an image side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, a third lens group having a positive refractive power, a fourth lens group having a positive refractive power, and a fifth lens group having a negative refractive power, wherein, during focusing, the first lens group, the third lens group, and the fifth lens group are fixed, and the second lens group and the fourth lens group are moved.

Abstract: A reflective type telephoto lens and a photographing apparatus including the reflective type telephoto lens are provided. The reflective type telephoto lens includes: a first lens that receives an incident flux of light from an object side; a main mirror including a reflective unit that reflects light transmitted through the first lens toward the object side, and a transmission portion disposed on a center portion thereof; a sub-mirror group including a sub-mirror that reflects light from the main mirror toward an image side; and a focusing lens group that focuses the light reflected by the sub-mirror.

Abstract: A telephoto zoom lens system includes a first lens group having a positive focal length, a second lens group having a negative focal length, a third lens group having a positive or negative focal length, a fourth lens group having a positive focal length, and a fifth lens group for performing hand shake compensation by allowing a portion of the fifth lens group to move perpendicularly to the optical axis. During zooming, the first and fifth lens groups are fixed and the second, third, and fourth lens groups move, and the third or fourth lens group is a focusing lens group.

Abstract: A lens system including: a first lens group having a positive refractive power; a second lens group having a positive refractive power; and a third lens group having a positive or negative refractive power, wherein the first lens group comprises four or less lenses, and the first through third lens groups are movable, independently, during focusing and have magnifications in a range from ?1 to 0.

Abstract: A telephoto zoom lens having four lens groups in a P-N-P-P configuration arranged sequentially from an object side. The first lens group includes a front group which is fixed when focusing and has a positive refractive power, and a rear group which moves when focusing and has a positive refractive power. The entire first lens group, including the front and rear groups, is fixed during zooming, and the second and third lens groups move during zooming. The second lens group compensates for shaking of an image plane caused by hand-shaking, by moving in a direction perpendicular to the optical axis, and satisfies the following condition: 1.2<f1a/f1b<1.8 where f1a and f1b denote the focal length of the front group of the first lens group and the focal length of the rear group of the first lens group, respectively.