This disclosure describes an afocal attachment that allows for alteration of received electromagnetic radiation (or light) prior to entry into the telescope. For example, a rifle scope may have a base magnification of 2, and the afocal attachment may allow magnification of a received image at levels ranging from 2 to 4. In this example, the entire telescope system with the afocal attachment installed will have an overall magnification of 4 to 8. In another example, the magnification of the telescope can be increased, transforming a telescope with a 4 magnification into a telescope with a higher effective magnification. In some instances the afocal attachment's optical axis can be configured to permit independent adjustment, allowing for easy removal and reinstallation of the afocal attachment without a need to re-adjust the telescope itself.

A mobile terminal according to the present invention comprises: a main body; a camera provided in the main body and comprising first and second lenses, which have different telephoto ratios; and a control unit for correlating, on the basis of a specific subject, a first image captured through the first lens with a second image captured through the second lens, wherein the control unit correlates a first region of the first image, in which a first graphic object corresponding to the specific subject is included, with the second image including a second graphic object corresponding to the specific subject and, when a preset manner of touching is applied to the first region of the first image in a state in which the first image is outputted on a touch screen, controls the touch screen such that the second image is outputted thereon.

A mobile terminal according to the present invention comprises: a main body; a camera provided in the main body and comprising first and second lenses, which have different telephoto ratios; and a control unit for correlating, on the basis of a specific subject, a first image captured through the first lens with a second image captured through the second lens, wherein the control unit correlates a first region of the first image, in which a first graphic object corresponding to the specific subject is included, with the second image including a second graphic object corresponding to the specific subject and, when a preset manner of touching is applied to the first region of the first image in a state in which the first image is outputted on a touch screen, controls the touch screen such that the second image is outputted thereon.

The rear converter lens consists of, in order from an object side: a first lens group that has a positive refractive power; a second lens group that has a negative refractive power; and a third lens group that has a positive refractive power. The first lens group consists of a cemented lens in which a negative lens concave toward the image side and a positive lens convex toward the object side are cemented. The second lens group consists of a cemented lens in which a negative lens concave toward the image side, a positive lens convex toward both sides, and a negative lens concave toward the object side are cemented. The third lens group consists of a cemented lens in which a positive lens convex toward the object side and a negative lens are cemented. The rear converter lens satisfies predetermined Conditional Expressions (1) and (2).

An object of the present invention is provide a coded aperture imaging apparatus that has a refocusing function and can change an angle of view. An imaging apparatus includes an imaging apparatus main body including a coded aperture, an imaging element that outputs a signal indicating a projected image of a subject, and an image restoration unit that reconstructs an image of a spatial domain based on the signal, and a lens attached to the imaging apparatus main body on a subject side from the coded aperture and changes an imaging angle of view in a state where the lens is attached to the imaging apparatus main body with respect to an imaging angle of view in a state where the lens is not attached to the imaging apparatus main body, in which the projected image is formed on the imaging element by the lens and the coded aperture.

A converter lens has negative refractive power, and is disposed on an image side of a master lens so that a focal length of an entire system becomes greater than a focal length of the master lens alone. The converter lens includes a first lens element closest to an object and a second lens element next to an image side of the first lens element with a space between the first lens element and the second lens element. A focal length of the converter lens, a focal length of an air lens formed by the first lens element and the second lens element, the shape of an image-side lens surface of the first lens element, and the shape of an object-side lens surface of the second lens element are determined as appropriate.

A converter optical system includes 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 a fifth lens having positive refractive power; wherein the first to fifth lenses are sequentially disposed in numerical order from the first lens to the fifth lens from an object side of the converter optical system to an image side of the converter optical system; and the fourth lens is bonded to either one or both of the third lens and the fifth lens.

A converter optical system includes 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 a fifth lens having positive refractive power; wherein the first to fifth lenses are sequentially disposed in numerical order from the first lens to the fifth lens from an object side of the converter optical system to an image side of the converter optical system; and the fourth lens is bonded to either one or both of the third lens and the fifth lens.

A converter optical system includes 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 a fifth lens having positive refractive power; wherein the first to fifth lenses are sequentially disposed in numerical order from the first lens to the fifth lens from an object side of the converter optical system to an image side of the converter optical system; and the fourth lens is bonded to either one or both of the third lens and the fifth lens.

A converter optical system includes 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 a fifth lens having positive refractive power; wherein the first to fifth lenses are sequentially disposed in numerical order from the first lens to the fifth lens from an object side of the converter optical system to an image side of the converter optical system; and the fourth lens is bonded to either one or both of the third lens and the fifth lens.