Asahi Kogaku Kogyo Kabushiki Kaisha

Asahi Kogaku Kabushiki Kaisha

Sukenori Shiba

Masahiro Oono

Tatsuya Yoshida

Noboru Saitoh

Koji Sato

Nobuyuki Nagai

Hisao Iwanade

Minoru Suzuki

Hisao Iwande

A lens position adjusting method for a zoom lens includes at least two movable lens groups, one lens group being primarily utilized for focusing and the other lens group being primarily utilized for magnification, wherein an object at a predetermined distance is in-focus when each movable lens group is positioned at each of respective initialized positions thereof with the zoom lens being set at a first focal length, and wherein each movable lens group is moved to vary magnification in accordance with a moving amount from the initialized positions of the movable lens groups. The lens position adjusting method includes: arranging a testing object at a position corresponding to a predetermined distance from the zoom lens; arranging a focal point detecting device at a reference focal plane or in the vicinity of the reference focal plane of the zoom lens; moving each movable lens group to each position at the first focal length; moving each movable lens group along an optical axis of the zoom lens so that a lens moving amount of each movable lens group is detected when a sharp image of the testing object is formed on the focal point detecting device via the zoom lens; making each of the positions of the movable lens groups as provisional initialized positions after completion of movement by the lens moving amount from the initialized positions; moving each movable lens group from the provisional initialized positions to positions at a predetermined focal length; detecting the lens moving amount by moving the movable lens group being chiefly utilized for focusing; obtaining a defocus amount from the lens moving amount; and obtaining an adjusting amount according to the defocus amount detected at given plurality of focal lengths so that each position of the movable lens group at which the in-focus state with the testing object is obtained at the first focal length serves as each adjusted initialized position.

Lens position adjusting method for zoom lens

An auto-focusing device of a camera includes a photographic lens having a focusing lens group guided along an optical axis, a stepping motor for moving the focusing lens group along the optical axis to bring an object into focus; and a controller for controlling the stepping motor to rotate stepwise when the depth of focus is smaller than a predetermined value and for controlling the stepping motor to rotate the rotor by even-numbered steps when the depth of focus of the photographic lens is greater than the predetermined value.

Motor-driven auto-focusing system

A stepping motor driving apparatus for a camera includes 1-2 phase excitation type stepping motors and a drive controller for driving and stopping the stepping motors so that the driven stepping motors are stopped always at a detent position.

Apparatus for driving stepping motor of camera

A stepping motor driving apparatus for a camera having a 1-2 phase excitation type stepping motor which is driven by a 1-2 phase excitation in response to a drive signal includes a drive control device for stopping the stepping motor at a 1-phase excitation position by de-energizing the stepping motor at the 1-phase excitation position and for stopping the stepping motor at a 2-phase excitation position while maintaining the excitation in a high precision drive control in which the stepping motor is driven at high precision. The drive control device stops the stepping motor by de-energizing the stepping motor always at the 1-phase excitation position in a normal drive control in which no precise drive control of the stepping motor is needed.

Apparatus for driving stepper motor of camera

A time-sharing drive apparatus for a camera having a plurality of motors includes a motor drive control system which alternately drives the motors in a time-sharing control. When the camera includes a zoom lens provided with a first stationary lens group, a second movable lens group and a third movable lens group, the motors are composed of a first motor which opens and closes a diaphragm of the zoom lens, a second motor which moves the second lens group, and a third motor which drives the third lens group. The motor drive control system which drives the first, second and third motors is controlled via a time-sharing system.

Time-sharing drive apparatus for motor of camera

An automatic focusing apparatus of a camera includes a photographing lens having a focusing lens group and a focus control mechanism which moves the focusing lens group to a hyper-focal distance position when no effective object distance is obtained.

Automatic focusing apparatus in a camera

A drive apparatus for a zoom lens barrel having at least two movable zooming lens groups which are moved upon zooming, comprising: two lens frames which support the movable zooming lens groups, two cam pins integral with the lens frames and extending in the same direction, two parallel rotatable drive plates which are provided with cam grooves in which the cam pins are fitted, and two drive units which drive the respective drive plates upon zooming. The cam profile of the cam grooves of the drive plates is such that the movable zooming lens groups are moved in predetermined directions by the rotation of the drive plates during zooming.

Drive apparatus for zoom lens barrel

A drive apparatus for a zoom lens barrel having a plurality of movable lens groups, comprising: a lens barrel body which supports lens frames of the movable lens groups to move linearly in the optical axis direction, a lens drive unit which is assembled independently of the lens barrel body, driven pins provided on the lens frames and projecting outward from the barrel body in the same direction, and a plurality of drive members having engaging portions engageable with the driven pins. The drive motor which independently drives the drive members and drive gears connects the drive members to the drive motor, is provided in said lens drive unit. The lens drive unit is secured to the lens barrel body in a state that the driven pins projecting from the lens barrel body are engaged by the engaging portions of the corresponding drive members of the lens drive unit.

A motor-driven diaphragm apparatus for a lens barrel having a plurality of lens groups and a diaphragm mechanism, in which a diaphragm block provided with a plurality of diaphragm blades and a diaphragm-opening-and-closing ring which opens and closes an aperture defined by the diaphragm blades, is integrally provided with a diaphragm-opening-and-closing arm that projects from the diaphragm block and that is provided with a radial association groove for the diaphragm-opening-and-closing ring. Also provided are front and rear lens barrel blocks which support the lens groups, wherein said diaphragm block is held between the front and rear lens barrel blocks so that the diaphragm-opening-and-closing arm and the association groove project outwardly.

Motor driven diaphragm apparatus for lens barrel

A drive apparatus for a zoom lens barrel having at least two movable lens groups, one of which is used also as a focusing lens group comprising: a pair of lens frames which respectively hold the two movable lens groups, a pair of driven pins which are integrally provided on the lens a drive cam plate which is provided with a pair of cam surfaces which engage with the corresponding driven pins and which is rotatable about an axis, a rack plate which is supported to move in the optical axis direction of the movable lens groups and which is provided with an engaging portion which engages with the driven pin of the movable lens group that is used also as a focusing lens group, a first drive mechanism which includes a first motor for swinging the drive cam plate in the forward and reverse directions, and a second drive mechanism which includes a second motor for moving the rack plate without having an influence on the angular position of the drive cam plate.

A drive apparatus for a zoom lens barrel having at least two movable lens groups, one of which is used also as a focusing lens group, comprising a pair of lens frames which respectively hold the two movable lens groups, a pair of driven pins which are integrally provided on the lens frames, a drive cam plate which is provided with a pair of cam surfaces which engage with the corresponding driven pins and which is rotatable about an axis, a drive mechanism which includes a motor for driving the drive cam plate, and a detection mechanism which detects the angular position of the drive cam plate. One of the cam surfaces that corresponds to the movable lens group, other than the focusing lens group, is defined by a stepped cam surface having discrete sections which are adapted to set the focal length discretely, so that no movement of the movable lens group takes place in the range of the angular position of the drive cam plate corresponding to the discrete sections. The other cam surface that corresponds to the movable lens group that functions not only as the zooming lens group but also as the focusing lens group is defined by a continuous cam surface which is adapted to move the movable lens group continuously when the drive cam plate is rotated in accordance with the object distance. The stop position of the drive cam plate during the zooming operation and the angular position of the drive cam plate during the focusing operation is controlled by the detection mechanism of the angular position of the drive cam plate.

A drive apparatus for a zoom lens barrel, in which at least two movable zooming lens groups are moved upon zooming, includes lens frames which respectively hold the two movable zooming lens groups, two parallel drive plates which are provided with cam grooves and which are pivoted to a common shaft to move the two movable zooming lens groups, a pair of drive gears which are in mesh with corresponding sector gears of the drive plates, and two drive mechanisms which individually drive the drive gears upon zooming.

A zoom electronic camera comprising a lens casing which contains therein a zoom lens having at least two movable zooming lens groups, a drive mechanism including a motor for driving the movable zooming lens groups, a solid state image pickup device which picks up an object image through the zoom lens, a lens CPU which controls the drive mechanism including the motor, and a body casing which contains therein a signal processing circuit which processes an image signal supplied from the solid state image pickup device and which is relatively rotatably connected to the lens casing through a cylindrical portion about which the relative rotation takes place. The zoom lens, the drive mechanism including the motor and the solid state image pickup device are located on the side of the cylindrical portion opposite to the lens CPU.

Zoom electronic camera

A lens barrel for holding an assembly or group of lens elements is molded as an integral member from a thermoplastic resin material such as polycarbonate, and at least two of the lens elements have different diameters. The lens barrel includes an outer cylindrical wall portion having a uniform diameter and a uniform wall thickness, and a lens holder portion integrally extending from an inner surface of the outer cylindrical wall portion. The lens holder portion is formed in accordance with the different diameters of the lens elements such that wall thickness is substantially uniform.

Thermoplastic lens barrel for holding assembly of lens elements

A color correction structure for a color imaging device in which a document is scanned in a predetermined direction by a slit exposure light. A light reflected on the document is lead to a photoconductive member along an optical path, and an image of the document is focused on the photoconductive member by a focusing lens which is arranged in the optical path. The color correction structure is provided with a plurality of filter members each transmitting reflected light having a predetermined wavelength, and at least one actuator for actuating the filter members in a direction substantially perpendicular to an extending direction of the slit exposure light, between a first position where the filter members are retracted from the light path and a second position where the filter members interferes with the light path. A controller controls the actuator for brightness and hue adjustments.

Growing community of inventors

Saitama-ken, Japan

Sukenori Shiba