A wide-angle optical system is a wide-angle optical system having a lens component. The lens component has a plurality of optical surfaces, in the lens component, two optical surfaces are in contact with air, and at least one optical surface is a curved surface. The wide-angle optical system includes in order from an object side, a first lens unit having a negative refractive power, a second lens unit, and a third lens unit having a positive refractive power. The second lens unit, for a focal-position adjustment, is moved between a first position and a second position along an optical axis. The third lens unit includes a cemented lens having a positive refractive power and a cemented lens having a negative refractive power, and following conditional expression (1) is satisfied:

0.05<fL/R31F<1.0   (1).

An objective optical system includes, in order from an object: a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power. The second lens group includes an aperture stop and moves at a time of changing magnification.

An optical unit includes a movable section that holds a movable lens group and includes a rotation restricting section, a fixed section that holds a fixed lens group and has specific permeability larger than 1.0, n thinned-down sections being provided in the fixed section, and a voice coil motor including an n magnet sections disposed at every (360/n)° around a center axis of the movable section and a coil section disposed in the fixed section. The n magnet sections are respectively housed in n thinned-down sections in a noncontact manner. The n thinned-down sections are formed in asymmetrical positions different from every (360/n)° around the center axis.

An endoscope has a configuration in which a wire guide tube is configured as a tube consecutively formed of polyetheretherketone from one end side to another end side, an opening penetrating is provided in a radial direction at part of a wall portion of a second coupling member into which an end part of the wire guide tube is inserted, a concave portion corresponding to the opening is provided at an outer peripheral surface of the end part of the wire guide tube, and a bonding agent integrally fills the opening and the concave portion to connect the wire guide tube and a coupling portion (the second coupling member).

An image pickup unit includes a brightness aperture configured to determine a brightness of an observation optical system and a light shielding aperture, and the light shielding aperture is configured to block some of predetermined light fluxes that pass through the brightness aperture when a movable lens frame moves toward a telephoto side.

Medical imaging camera head devices and methods are provided using light captured by an endoscope system or other medical scope or borescope. Afocal light from the scope is manipulated and split. The resulting first and second beams are passed through focusing optics to a single sensor. To take better advantage of the available number image sensor pixels, the beam may pass through lens elements (or prisms) to generate an anamorphic aspect ratio prior to being split, increasing the resolution of the image in one dimension. The afocal anamorphic beam is then split, and both images are focused on the image sensor. The anamorphism is compensated for in image processing, permitting higher resolution in one dimension along the image sensor. The manipulation of the beams prior to being split (and in some cases after or while being split) can take several forms, each offering distinct advantages over existing systems.

An image-acquisition apparatus is provided with: an imaging optical system; and an image-acquisition device that acquires parallax images, wherein the imaging optical system is provided with a first negative lens group, a first positive lens group, and a second positive lens group, wherein the first positive lens group and the first negative lens group are disposed along a common center axis, wherein the second positive lens group is provided with two positive lens groups that are disposed next to each other in a parallax direction on either side of the common center axis and that individually have center axes, wherein two aperture stops having openings, wherein the first positive lens group has only one moving lens group that is moved, and wherein all of remaining lens components in the imaging optical system, excluding the moving lens group, remain still.

The objective optical 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 having a positive refractive power. Focusing is carried out by moving the second lens group. The third lens group includes a positive lens and a cemented lens, and the cemented lens includes a positive lens and a negative lens. A first sub-unit includes a lens positioned on the object side of a predetermined air space and a second sub-lens group includes a lens positioned on an image side of the predetermined air space. The predetermined air space is the maximum air space among the air spaces in the third lens group.

An observation device and method its operation is disclosed. The device includes an instrument with a shaft having a proximal end and a distal end; objective optics disposed at the shaft and having a field of view; an imaging sensor arranged to capture image data, the imaging sensor having a sensor array of evenly distributed elements; and an image processing unit. The objective optics is arranged to capture a scene in the field of view on the imaging sensor. The objective optics define at least a central imaging region and a peripheral imaging region, where the differing focal lengths of the objective optics result in the central imaging region having a higher digital resolution than that of the peripheral region, resulting in more pixels dedicated to the region of interest, while the peripheral regions have adequate resolution to monitor the introduction of surgical tools and other valuable information.

Disclosed are an adaptor lens for increasing a magnification of a scope and a sight comprising the same. The adaptor lens for increasing a magnification of a scope of the present invention comprises: an adapter lens body detachably coupled to a sight main body having an objective lens group; a convex lens part provided in the adapter lens body so as to be disposed in front of the objective lens group; and a concave lens part provided in the adapter lens body and disposed between the convex lens part and the objective lens group.