An attachment optical system includes a first converter optical system attachable to an object side of an imaging optical system, and a second converter optical system attachable to an image side of the imaging optical system. The first converter optical system includes a dome-shaped cover and at least one positive lens. A predetermined condition is satisfied.

An optical system for converting light from an object into parallel light, and guiding the parallel light to a plurality of image forming units each configured to form an image of the object includes a first lens unit having positive or negative refractive power and a second lens unit having positive refractive power that are disposed in order from an object side, wherein the first lens unit and the second lens unit are disposed at a widest interval in the optical system, and wherein the first lens unit consists of at least one positive lens and at least one negative lens that are disposed in order from the object side.

A system comprises a sensor subsystem for imaging an object space, and a telescope for coupling electromagnetic energy from the object space to the sensor subsystem. The system comprises a bypass optical path that bypasses the telescope on the way to the sensor subsystem in order to provide a larger field of view of the object space. The bypass path and the telescope path merge at a merging point between the telescope and the sensor subsystem, and are disjoint upstream of the merging point. A simple bypass configuration is therefore provided, with possibly just a single fold mirror at the merging point. A sensor may form an intermediate image, and a frame is placed at the intermediate image to reject stray radiation and provide a real and accessible intermediate pupil for the sensor. Other features are also provided.

A camera module, an electronic device, and a camera module control method are provided. The camera module includes: a first bracket; a lens, where the lens is disposed on the first bracket; a camera assembly, where the camera assembly includes a camera and a second bracket, the camera is disposed on the second bracket, the second bracket is slidably sleeved on the first bracket, and an optical axis direction of the lens is parallel to an optical axis direction of the camera.

A mid-wave infrared (MWIR) discrete zoom lens for use with remote surveillance and identification having a dual focal length of 9 and 6.39 inches and F #2.8 and F #2, respectively. In one case, a full field of view is about 30.8 degrees for a 9 inch focal length configuration and about 43 degrees for a 6.39 inch focal length configuration. The lens is corrected for monochromatic and chromatic aberrations over the wavelength range 5100 nm-3300 nm. The focal plane may constitute a pixel array consisting of MWIR sensitive material (e.g. InSb, HgCdTe, nBn, SLS, etc.) for use in high-resolution, wide-area imaging applications.

A mid-wave infrared (MWIR) discrete zoom lens for use with remote surveillance and identification having a dual focal length of 9 and 6.39 inches and F #2.8 and F #2, respectively. In one case, a full field of view is about 30.8 degrees for a 9 inch focal length configuration and about 43 degrees for a 6.39 inch focal length configuration. The lens is corrected for monochromatic and chromatic aberrations over the wavelength range 5100 nm-3300 nm. The focal plane may constitute a pixel array consisting of MWIR sensitive material (e.g. InSb, HgCdTe, nBn, SLS, etc.) for use in high-resolution, wide-area imaging applications.

A Mid-Wave Infrared (MWIR) objective and relay lens system has an F# of 3.33 and angular field of view of 15.28°. It is deployed, with a focal plane and scanning system, on airborne platforms for wide area motion imagery. It is corrected for monochromatic and chromatic aberrations over of 3.3 to 5.1 micrometers. Effective focal length is 20 inches, and the overall length is 40.70 inches. The lens has, from object to image, two groups of optical elements with a cold shield/aperture stop 6 inches from the image plane. Group 1 acts as an objective lens with a positive power and three elements, Group 2 acts as a relay lens has a positive power and four elements. The lens is made of Germanium and Silicon. It used in a scanning system in a pre-objective configuration where the fast scan mirror is located in front of the lens system.

A Mid-Wave Infrared (MWIR) objective and relay lens system has an F# of 3.33 and angular field of view of 15.28°. It is deployed, with a focal plane and scanning system, on airborne platforms for wide area motion imagery. It is corrected for monochromatic and chromatic aberrations over of 3.3 to 5.1 micrometers. Effective focal length is 20 inches, and the overall length is 40.70 inches. The lens has, from object to image, two groups of optical elements with a cold shield/aperture stop 6 inches from the image plane. Group 1 acts as an objective lens with a positive power and three elements, Group 2 acts as a relay lens has a positive power and four elements. The lens is made of Germanium and Silicon. It used in a scanning system in a pre-objective configuration where the fast scan mirror is located in front of the lens system.

A device comprising at least two body sections is disclosed. The first body section comprises an imaging unit and a magnet movably connected to the imaging unit, and the second body section comprising an optical unit with a magnet fixed to the optical unit. The magnet movably connected to the imaging unit may be sliding along a guiding element. The body sections are also in a movable connection with each other, and the device is operable in at least two modes. In the first mode the imaging unit and the optical unit are fixed in a set relative position due to magnetic interaction between the magnets, and in the imaging unit is positioned away from the optical unit. In the second mode the units are positioned apart from each other.

An extender lens changes a focal length of an entire lens system after replacement to a longer focal length side than a focal length of a master lens by replacing a part of the master lens with the extender lens. The extender lens consists of, in order from an object side to an image side, a first lens group, and a negative second lens group. The first lens group is a lens group that has a positive refractive power as a whole and has a shortest focal length among lens groups consisting of one lens component or a plurality of consecutively arranged lens components. The extender lens satisfies a predetermined conditional expression.