摘要:
A zoom lens barrel includes a stationary barrel; a first rotational feed barrel which is engaged with the stationary barrel by means of helicoids; a first linear movement barrel which is engaged with the first rotational feed barrel so as to relatively rotate and to relatively move together along the optical axis and which is provided on the inner peripheral surface thereof with a female helicoid; a second rotational feed barrel which has a male helicoid and a female helicoid on the outer and inner peripheral surfaces thereof respectively; a rotational transmission barrel which is engaged with the first rotational feed barrel so as to relatively move along the optical axis and to rotate together, and which is integrally connected to the second rotational feed barrel; a second linear movement barrel which is provided on outer peripheral surface thereof with a male helicoid which engages with the female helicoid of the second rotational feed barrel; a lens group that is held by said second rotational feed barrel; and at least one lens group which is guided to linearly move independently of the second linear movement barrel.
摘要:
Disclosed is a linear guiding mechanism of a zoom lens barrel which includes: a first cylindrical member provided on an inner periphery thereof with at least one linear guide groove which extends parallel to an optical axis, a code sheet for detecting a focal length being fixed to an outer periphery of the first cylindrical member; and a second cylindrical member provided on an outer surface thereof with at least one guide projection which is fitted in the at least one linear guide groove, respectively, wherein at least part of the code sheet and at least part of the at least one linear guide groove are located at the same position in a circumferential direction of the code sheet, and wherein each of the at least one linear guide groove includes a raised portion which is radially raised from the base of the linear guide groove towards the optical axis.
摘要:
A brush mounting structure for an encoder in a zoom lens barrel includes a code plate and a brush operatively arranged in a zoom lens barrel which constitute an encoder which detects the focal length in accordance with a relative sliding movement between the code plate and the brush; and a helicoid lens barrel member which is provided with a helicoid portion and which constitutes the zoom lens barrel. The brush is provided on the helicoid portion of the helicoid lens barrel. A focal length detection circuit in the zoom lens barrel is also disclosed.
摘要:
A control method for a zoom lens camera which includes a focal length detection mechanism which detects the focal length divided into a finite number of steps; and a focus drive mechanism which drives the focusing lens group to move the same to the finite number of steps, the method includes measuring actual focal points of the zoom lens system at the wide angle extremity and the telephoto extremity, whereby any deviations of the focal points from a focal plane are obtained; converting the deviations to a displacement of said focusing lens group at each focal length of said finite number of steps, taking into account the focus sensitivity of said focusing lens group, wherein the data of said displacement is stored in a memory; and driving the focusing lens group, upon focusing, in accordance with the displacement of said focusing lens group determined based on object distance data and focal length data, in addition to the stored displacement data. A zoom lens camera to which the control method is applied is also disclosed.
摘要:
A multi-stage extension type zoom lens barrel includes a first rotational feed barrel rotatably connected to a stationary barrel; a first linear movement barrel disposed in, and rotatably connected to, the first rotational feed barrel without relatively moving in the optical axis direction; a second rotational feed barrel disposed in, and rotatably connected to, the first linear movement barrel so as to move in the optical axis direction relative to the first linear movement barrel upon rotating; a rotation transmission barrel which can be detachably inserted between the first rotational feed barrel and the first linear movement barrel from the front thereof; a rotation transmission groove and a projection which connects the rotation transmission barrel and the first rotational feed barrel so as to relatively move in the optical axis direction without relatively rotating; connection members provided at the front ends of the rotation transmission barrel and the second rotational feed barrel; and a connection holding decoration ring detachably attached to the front ends of the second rotational feed barrel and the rotation transmission barrel via a predetermined amount of deformation, so as to hold the connection of the barrels.
摘要:
A zoom lens camera includes an image size varying frame to switch the image size between a standard image plane and a laterally elongated image plane, a linear movement barrel, an FPC board which connects a shutter unit and a controller, and a light-interception plate which is secured to a rear end of the linear movement barrel. The light-interception plate is provided with a rearwardly projecting planar portion which at least partly overlaps the image size varying frame as viewed in an optical axis direction, regardless of the position of the image size varying frame. Further the planar portion is provided with an FPC board receiving portion which supports the FPC board along the cylindrical surface of the linear movement barrel.
摘要:
Disclosed is an engaging structure of two cylindrical members. At least part of one of the two cylindrical members is coaxially fitted on the other cylindrical member. The engaging structure includes: a plurality of radial projections formed on the second cylindrical member; two annular flanges formed on the other cylindrical member to form a circumferential groove therebetween, the plurality of radial projections being fitted in the circumferential groove; and a plurality of cut-away portions, formed on one of the two annular flanges, through which the plurality of radial projections are respectively inserted into the circumferential groove. Each corresponding pair of the plurality of projections and the plurality of cut-away portions are formed to have a circumferential width different from those of the other corresponding pairs of the plurality of projections and the plurality of cut-away portions. At least one of corresponding pairs of the plurality of projections and the plurality of cut-away portions are formed to have a radial length different from those of the other corresponding pairs of the plurality of projections and the plurality of cut-away portions.
摘要:
An inner barrel includes a male helicoid, and an outer barrel includes a female helicoid which can engage with the male helicoid of the inner barrel. The included angle of trapezoidal threads of the male helicoid are identical to an included angle of trapezoidal grooves of the female helicoid in a section perpendicular to a direction of an extension of the threads.
摘要:
An encoder for detecting a forward/reverse movement of a rotatable object includes a rotating shaft that is supported on a base and rotates in accordance with the movement of the subject, two rotating disks fixed to the rotating shaft, and two photocouplers mounted on the base which are associated with the disks. Each of said rotating disks is formed with a predetermined light modulating pattern to vary the intensity of light along a circumferential direction. Each of the photocouplers emits a light toward the rotating disk and detects the light modulated by the pattern on the rotating disk. The angular relationship between the rotating disks is selected such that the output signals from the photocouplers due to the rotation of the rotating shaft have a predetermined phase difference.
摘要:
A method for producing a male helicoid molding die which is adapted to manufacture an inner barrel having a male helicoid, and for producing a female helicoid molding die which is adapted to manufacture an outer barrel having a female helicoid which can engage with said male helicoid of the inner barrel. The method includes the steps of firstly, setting an included angle of trapezoidal threads of the male helicoid to be identical to an included angle of trapezoidal grooves of the female helicoid in a section perpendicular to a direction of an extension of the threads and preparing a cutting tool having an angle identical to the set angle. Secondly, the male helicoid molding die is machined to form a helicoid portion thereof using the cutting tool. Next, an electric spark machining electrode is prepared having a helicoid portion whose shape is identical to a shape of the helicoid portion of the male helicoid molding die, by a mechanical cutting operation, using the cutting tool. Then a helicoid portion of the female helicoid molding die is formed by electric spark machining using the electric spark machining electrode.