To secure a smooth rotating state of a rotary drive body with a simple structure without deteriorating the characteristics of an ultrasonic motor. Provided are an ultrasonic motor including a rotor and a stator, a rotary drive body that moves an optical device in an axial direction by being rotated around an axis by driving force of the ultrasonic motor, a bearing rotatable around the axis, and a compression spring that applies axial bias force to the ultrasonic motor, the rotary drive body, and the bearing. The rotor and the stator are biased in a contact direction and the rotary drive body and the bearing are biased in a contact direction by the compression spring.

The invention relates to the field of digital photo- and video-recording, and may be used for recording and monitoring distant objects, such as expanses of forest. The technical result is directed at enhancing the focus quality of the images produced. A method for producing a photo- or video-image of at least one object to be recorded, consisting in: producing an image of an object to be recorded by means of an electronic optical device; wherein, a focusing object, corresponding to at least one object to be recorded and satisfying the following conditions, is first selected for the object to be recorded: the focusing object has higher contrast than the object to be recorded, and the object to be recorded is located within the bounds of the depth of field. Then, an image is produced of the at least one object to be recorded, in which the electronic optical device is focused on the focusing object corresponding to the object to be recorded, the focusing parameters are set, and said focusing parameters are used for producing an image of the object to be recorded.

There are provided a variable magnification optical system and a control method thereof which are capable of relatively accurately adjusting a positional relationship between a variable magnification optical device and an imaging surface of an imaging device according to a zoom amount. A zoom lens included in the variable magnification optical device is positioned at a telephoto end and a wide angle end, and shift amounts S1 and S2, tilt angles 1 and 2, rotation angles 1 and 2, and focusing adjustment amounts 1 and 2 of the variable magnification optical device are set by a user and are stored. In a case where a zoom amount of the zoom lens is set to a desired value by the user, a shift amount corresponding to the set zoom amount is calculated by using the stored shift amounts S1 and S2. The positional relationship between the variable magnification optical device and the imaging surface of the imaging device is adjusted so as to have the calculated shift amount.

An optical system includes an objective of the zoom type and a depth-estimating optical detecting unit, the depth-estimating optical detecting unit including a matrix array of micro-lenses and a matrix-array detector, the matrix array of micro-lenses being arranged so that the image of the focal plane of the zoom is focused by the matrix array of micro-lenses on the plane of the matrix-array detector. The optical system calculates, for a first focal length of the zoom and for a given object, the estimated distance of this object and the measurement uncertainty in this estimation, depending on the first focal length and the estimated distance and, this estimated distance being known, optimizes by allowing at least one second focal length of the zoom to which a lower measurement uncertainty in this estimation corresponds to be determined.

A device may include an input component and a focus control component. The focus control component may receive, from the input component, an input associated with adjusting a focus of a field of view of the device. The focus control component may determine whether an area of interest is present in the field of view. The focus control component may adjust, based on determining that the area of interest is not present in the field of view, the focus of the field of view at a focus speed associated with the input, or, based on determining that the area of interest is present in the field of view, may determine one or more parameters for modifying the focus speed, modify the focus speed based on the one or more parameters, and adjust the focus of the field of view at the modified focus speed.

An imaging optical system includes: a front group having positive power; an aperture stop; a single lens Fn arranged adjacent to the aperture stop and having negative power; and a rear group having power. The front group includes: a first lens having positive power; a second lens having negative power; and a lens LG1R having positive power. The rear group includes a lens LGnR having negative power and located closest to the image. While focusing to make a transition from an infinity in-focus state to a close-object in-focus state, neither the front group nor the rear group moves but the single lens Fn moves along an optical axis toward the image. The imaging optical system satisfies the inequality: 0.38<fLG1R/fG1<1.75, where fG1 is a focal length of the front group and fLG1R is a focal length of the lens LG1R.

A focus adjustment control apparatus is provided which includes: a focus detection unit that calculates an evaluation value with regard to contrast of an image via an optical system to detect a focus adjustment state of the optical system; an acquisition unit that acquires from a lens barrel at least one of a maximum value and a minimum value of an image plane movement coefficient that represents correspondence relationship between a movement amount of a focus adjustment lens included in the optical system and a movement amount of an image plane; and a control unit that uses at least one of the maximum value and the minimum value of the image plane movement coefficient to determine a drive speed for the focus adjustment lens when the focus detection unit detects the focus adjustment state.

A method is disclosed for ascertaining a focus image distance of an optical sensor, which is provided with a lens, of a coordinate-measuring apparatus onto a workpiece to be measured, wherein the optical sensor and/or the workpiece are movable in a Z direction such that a distance in the Z direction between the workpiece and the optical sensor is variable. Further, a corresponding coordinate-measuring apparatus and a computer program product are disclosed.

At least one embodiment of an imaging apparatus has: an imaging plane capable of being curved; an evaluation unit that determines an evaluation value indicating a degree of in-focus of an image signal from the imaging element; an adjustment unit adjusting a position of the focus adjustment lens to a position with the highest evaluation value; and a control unit that controls the curvature of the imaging plane for correcting an image plane curve in the optical system and for bringing the image signal into focus. When the adjustment unit adjusts the position of the focus adjustment lens to an end portion of the movable area, the curvature of the imaging plane is controlled for bringing the image signal into focus on a priority basis.

A focus adjustment device obtains a correction value for correcting a result of autofocus, from aberration information regarding at least one of an astigmatism, a chromatic aberration, and a spherical aberration of an imaging optical system, and focus detection information regarding the autofocus. The focus adjustment device then controls a position of a focusing lens that the imaging optical system has, based on a result of the autofocus corrected using the correction value. By correcting the result of the autofocus while considering at least a focus condition of a photographic image, a focus detection error caused by an aberration of the optical system can be accurately corrected.