JP2017215395A - Imaging lens - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging lens capable of increasing the rotation angle of an operation ring for optical element adjustment such as focus/zoom/iris of an imaging lens, in which a required optimum operation rotation angle is different from each other depending on the imaging purpose, without reducing the strength of lens structure body.SOLUTION: The imaging lens is configured that the functional adjustment of optical elements is made via a rotation member which rotates on the optical axis. The imaging lens has a second cam follower engaged with a second cam groove formed in a direct cam ring 6 which is implanted with a first cam follower engaged with a first cam groove formed in the inner periphery of a manual operation member 8, in which the second cam follower is formed protruding on the outer periphery of the rotation member.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a photographic lens, and more particularly to a lens operation mechanism having means for performing an adjustment operation of an optical adjustment element such as focus / zoom / iris from a rotation angle of an operation ring rotating around an optical axis.

  Conventionally, when the drive input of the optical adjustment element is performed by a cam follower, by changing the lead of the cam of the operation ring provided with the cam that engages the cam follower when the rotation trajectory of the cam follower is not orthogonal to the optical axis There was a means to change the rotation angle of the operating ring.

  In Patent Document 1, a pin planted on the outer periphery of a movable cylinder having a male screw threadedly engaged with a fixed cylinder provided with a helicoid female screw on the inner periphery is inserted through a relief groove provided on the fixed cylinder, and a fixed amount is provided on the inner periphery. A structure that engages with an operation ring provided with a guide groove having a lead is disclosed.

Japanese Patent Laid-Open No. 06-308362

  However, in the prior art disclosed in Patent Document 1 described above, the operation rotation angle of the operation ring can be set only when the pin trajectory has a predetermined lead, and the pin trajectory is a simple arc around the optical axis. Not applicable when drawing.

  Therefore, an object of the present invention is to achieve an enlargement of the rotation angle of the operation ring in the optical adjustment element made by a cam follower in which the drive input draws an arc trajectory centered on the optical axis, enabling fine adjustment of each element. The goal is to provide a robust lens.

In order to achieve the above object, a photographic lens according to the present invention includes:
In a photographing lens in which the function adjustment of the optical element is performed by a rotating member that rotates about the optical axis, a first cam follower that is engaged with a first cam groove provided on the inner periphery of the manual operation member is implanted. A second cam follower that engages with a second cam groove provided in the linear cam ring is provided on the outer periphery of the rotating member.

  According to the present invention, in the photographing lens in which the function adjustment of the optical element is performed by a rotating member that rotates about the optical axis, the rotation angle of the operation ring can be increased by simply changing the lens exterior structure. A robust lens that can be fine-tuned can be provided.

Sectional drawing and expansion | deployment figure of the lens housing in 1st Example of this invention FIG. 1 is a cross-sectional view and a developed view of a lens housing when the manual operation member in FIG. Sectional drawing and expansion | deployment figure of a lens housing at the time of rotating the whole region of the rotation area | region of the manual operation member in FIG. Sectional drawing and expansion | deployment figure of the lens housing in 2nd Example of this invention FIG. 4 is a cross-sectional view and a developed view of the lens housing when the half of the rotation region of the manual operation member in FIG. 4 is rotated. FIG. 4 is a cross-sectional view and a development view of the lens housing when the entire operation ring rotation region in FIG. 4 is rotated.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view and a developed view of a lens housing according to the first embodiment of the present invention. FIGS. 2 and 3 respectively show a sectional view and a developed view of the lens housing when the manual operation member in FIG. FIG. 4 is a cross-sectional view and a development view of a lens housing according to the second embodiment of the present invention. Further, FIGS. 5 and 6 respectively show a sectional view and a developed view of the lens housing when the half of the rotation region of the manual operation member in FIG. 4 or the entire region is rotated.

  The lens operating mechanism according to the first embodiment of the present invention will be described below with reference to FIGS.

  In FIG. 1, the movable barrel 1 is engaged with a plurality of straight grooves 2 a provided in a fixed cylinder 2 parallel to the optical axis direction, and a cylindrical cam member 3 fitted to the inner periphery of the fixed cylinder 2. A plurality of cam followers 4 that engage with the plurality of guide grooves 3 a provided are projected in a direction perpendicular to the optical axis. The cylindrical cam member 3 is only allowed to rotate around the optical axis, and the movable lens barrel 1 held by the plurality of cam followers 4 has the plurality of straight grooves 2a and Guided by the plurality of guide grooves 3a. As a result, the movable lens barrel 1 moves in the optical axis direction by a distance corresponding to the rotation angle of the cylindrical cam member 3.

  The cylindrical cam member 3 is provided with a cam follower 5 projecting so that the cylindrical cam member 3 can be rotated from the outside of the fixed cylinder 2, and the fixed cylinder does not interfere with the entire rotation area of the cam follower 5. 2 is provided with a relief groove 2b. A linear motion cam ring 6 is fitted on the outer periphery of the fixed cylinder 2 so as to be slidable in the optical axis direction, and a cam follower 7 is implanted in the linear motion cam ring 6. The cam follower 5 is inserted into the escape groove 2 b and engaged with a guide groove 6 a provided in the linear cam ring 6. Next, the cam follower 7 is engaged with a straight groove 2c parallel to the optical axis provided in the fixed cylinder 2 in the optical axis direction from the linear cam ring 6, and in the optical axis centrifugal direction, the manual operation member 8 is engaged. Is engaged with a guide groove 8a provided on the inner periphery of the guide. The linear cam ring 6 is restricted from rotating around the optical axis by the cam follower 7 engaged with the linear groove 2c, and is allowed to move only in the optical axis direction.

  When the manual operation member 8 is rotated around the optical axis in the configuration as described above, the linear cam ring 6 moves in the optical axis direction as the cam follower 7 moves along the intersection track of the guide groove 8a and the straight groove 2c. Go straight to. Further, since the guide groove 6a provided in the linear cam ring 6 linearly moves in the optical axis direction, the cylindrical cam member 3 on which the cam follower 5 engaged with the guide groove 6a is protruded around the optical axis. Rotate.

  In FIG. 2, when the manual operation member 8 is rotated by β / 2 which is half of the total rotation angle β, the linear cam ring 6 and the guide groove 6a emit light by x / 2 which is half of the total displacement x. Displace in the axial direction. Since the cam follower 5 engaged with the guide groove 6a protrudes from the cylindrical cam member 3 which is allowed to rotate only around the optical axis, the guide groove 6a allows only α / 2 which is half of the total rotation angle α. The cylindrical cam member 3 is rotated. By this rotation, the movable lens barrel 1 is guided by the straight groove 2a and the plurality of guide grooves 3a, and the movable barrel 1 moves by a predetermined amount in the optical axis direction.

  In FIG. 3, when the manual operation member 8 is rotated by the full rotation angle β, the linear cam ring 6 and the guide groove 6a are displaced in the optical axis direction by the total displacement amount x. Further, the cylindrical cam member 3 is rotated to the end by the guide groove 6a and the cam follower 5 engaged therewith. This rotation guides the straight groove 2a and the plurality of guide grooves 3a, and the movable barrel 1 completes the movement of the total movement amount in the optical axis direction.

  As described above, the ratio β / α between the rotation angle of the manual operation member 8 and the rotation angle of the cylindrical cam member 3 is determined by the ratio of the inclination of the guide groove 8a and the guide groove 6a. The setting of the rotation amount of the member 8 and the movement amount of the movable barrel 1 can be freely changed.

  Here, since the escape groove 2b is formed on the fixed cylinder 2 at an angle equal to or greater than the total rotation angle α of the cylindrical cam member 3, the larger the angle of the escape groove 2b, the lower the strength of the photographing lens body. I will invite you. In this embodiment, since the value of the rotation angle ratio β / α can be set freely, it is possible to provide a robust lens in which the angle of the relief groove 2b is made as small as possible.

  The lens operating mechanism according to the second embodiment of the present invention will be described below with reference to FIGS. Here, the same members as those described in the first embodiment will be described with the same numbers.

In FIG. 4, a fixing member 10 containing a plurality of diaphragm blades 9 is fixed to the inner periphery of the fixed cylinder 2. The plurality of aperture blades 9 perform in-plane motion perpendicular to the optical axis along the trajectories of a plurality of cams 11a (not shown) provided on the cam member 11 that rotates around the optical axis inside the fixed member 10. The opening / closing state of the diaphragm is adjusted according to the rotation angle of the cam member 11. Here, a cam follower 5 is projected from the cam member 11, and like the cylindrical cam member 3 in the first embodiment, the fixed cylinder 2 can be rotated so that the cam member 11 can be rotated from the outside. An escape groove 2 b is provided so as not to interfere with the entire rotation area of the cam follower 5.

  The following configuration is the same as that of the first embodiment. When the manual operation member 8 is rotated around the optical axis, the linear cam is moved as the cam follower 7 moves along the intersection track of the guide groove 8a and the straight groove 2c. The ring 6 moves straight in the optical axis direction. Further, since the guide groove 6a provided in the linear cam ring 6 linearly moves in the optical axis direction, the cam member 11 provided with the cam follower 5 engaged with the guide groove 6a is rotated around the optical axis. Let

  In FIG. 5, when the manual operation member 8 is rotated by β / 2 which is a half of the total rotation angle β, the linear cam ring 6 and the guide groove 6a emit light by x / 2 which is a half of the total displacement x. Displace in the axial direction. The cam follower 5 engaged with the guide groove 6a is protruded from the cam member 11 which is allowed to rotate only around the optical axis. Therefore, the guide groove 6a has a half of the rotation angle α by α / 2. The cam member 11 is rotated. By this rotation, the plurality of aperture blades 9 are half-opened along the tracks of the plurality of cams 11a.

  In FIG. 6, when the manual operation member 8 is rotated by the full rotation angle β, the linear cam ring 6 and the guide groove 6a are displaced in the optical axis direction by the total displacement amount x. Further, the cam member 11 is rotated to the end by the guide groove 6a and the cam follower 5 engaged therewith. By this rotation, the plurality of diaphragm blades 9 are fully opened along the tracks of the plurality of cams 11a.

  Accordingly, the ratio β / α of the rotation angle of the manual operation member 8 and the rotation angle of the cam member 11 is determined by the ratio of the inclination of the guide groove 8a and the guide groove 6a. The setting of the amount and the open / close state of the aperture can be freely changed.

  Also in this embodiment, since the value of the rotation angle ratio β / α can be freely set as in the first embodiment, a robust lens can be provided by making the angle of the escape groove 2b as small as possible.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to this embodiment, A various deformation | transformation and change are possible within the range of the summary.

  This is used as a lens operation rotation angle changing means for adjusting the built-in optical element by rotating the manual operation ring around the optical axis.

1 moving barrel, 2 fixed cylinder, 2a plural straight grooves, 2b relief groove, 2c straight groove,
3 cylindrical cam member, 3a multiple guide grooves, 4 multiple cam followers, 5 cam followers,
6 linear motion cam ring, 6a guide groove, 7 cam follower, 8 manual operation member, 8a guide groove,
9 Plural diaphragm blades, 10 fixing member, 11 plural cams, 11a plural cam followers

Claims (2)

  In a photographic lens in which the position adjustment of a movable barrel that moves linearly in the optical axis direction is performed by rotation of a manual operation member around the optical axis, the manual operation member, linear cam ring, fixed cylinder, cylinder from the outside of the lens The cam member and the movable lens barrel are arranged in this order. The cylindrical cam ring is fitted to the inner periphery of the fixed cylinder, and the linear cam ring and the manual operation ring are fitted to the outer periphery of the fixed cylinder. A first cam groove provided on the inner periphery of the manual operation member and engaged with the first cam follower implanted in the linear cam ring movable only in the optical axis direction; Further, a second cam follower provided on the outer periphery of the cylindrical cam member is inserted into a second cam groove provided in the linear cam ring through a relief groove provided in an arc shape around the optical axis in the fixed cylinder. A plurality of third cam followers projecting from the outer periphery of the movable barrel The third imaging lens characterized by engaging the plurality of linear grooves parallel to the optical axis provided in the fixed cylinder while engaged with the cam a plurality of through provided in the cylindrical cam member.   In a photographic lens in which the opening / closing adjustment of the aperture mechanism is performed by the rotation of the manual operation member about the optical axis, the manual operation member, the linear cam ring, the fixed cylinder, the cylindrical cam member, and the aperture mechanism are arranged in this order from the outside of the lens. The fixed member of the throttle mechanism is fitted to the inner periphery of the fixed cylinder, and the linear cam ring and the manual operation ring are fitted to the outer periphery of the fixed cylinder. A first cam groove is provided on the inner periphery of the manual operation member and engages with a first cam follower that is implanted in the linear cam ring that is movable only in the optical axis direction. A second cam follower projecting from the outer periphery of the cam member of the aperture mechanism is inserted into and engaged with the second cam groove provided through an escape groove provided in an arc around the optical axis. A plurality of cam members of the diaphragm mechanism as the cam member rotates about the optical axis. Taking lens and a plurality of cams for guiding the diaphragm blades in a predetermined open or closed state is provided.