JP5168024B2 - Lens barrel and imaging device - Google Patents

Description

  The present invention relates to a lens barrel and an imaging apparatus.

There is a lens barrel that includes a guide shaft that guides the moving direction of a lens, and a frame that has a bearing that engages with the guide shaft and holds the lens (see Patent Document 1). The bearing abuts against the guide shaft by a pair of substantially V-shaped surfaces. Guided by the guide shaft, the frame moves in the extending direction of the guide shaft.
Japanese Patent Laid-Open No. 2007-232828

  When driving the lens frame in the lens barrel, there is a structure in which a cam follower is mounted on the outer peripheral surface of the lens frame and the cam follower is driven by the cam groove of the rotating cam barrel. In such a structure, the force applied to the cam follower by being pushed by the cam groove may urge one surface of the V-shaped bearing downward with respect to the guide shaft to tilt the central axis of the lens.

In order to solve the above-mentioned problem, as a first aspect of the present invention, a shaft member (142, 144) provided in the fixing portion (140) and a first surface that abuts the shaft member, faces each other and intersects with each other. A lens holding member (130, 160) having a groove (131, 161) including (182) and a second surface (184) and movable along the shaft member while holding the lens (124, 134); A drive member (150) for driving the lens holding member along the shaft member, and an engaging portion (engaged with the drive member) and disposed closer to the first surface than the second surface on the peripheral surface of the lens holding member ( 136, 166), and the lens barrel (100) is provided in which the groove portion is inclined to the engaging portion side.

  As a second aspect of the present invention, there is provided an imaging apparatus (300) having the lens barrel (100) and an imaging unit (200) that captures an image formed using the lens barrel. The

  The above summary of the present invention does not enumerate all necessary features of the present invention. Also, a sub-combination of these feature groups can be an invention.

  Hereinafter, the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solving means of the invention.

  FIG. 1 is a sectional view of the entire lens barrel 100. The lens barrel 100 includes an optical system 101 having a first lens group 114, a second lens group 124, and a third lens group 134. The first lens group 114, the second lens group 124, and the third lens group 134 are held by lens frames 112, 122, and 132, respectively.

  The fixed cylinder 140 is formed integrally with a mount connected to another member such as a camera body, and does not move or rotate with respect to the camera body or the like. In addition, the fixed cylinder 140 supports the guide bar 142 and the guide bar 144 in parallel to each other at positions facing the radial direction.

  The first lens group 114 is held on the front tube 111 via the lens frame 112. That is, the front cylinder 111 and the lens frame 112 form the front group unit 110. The front cylinder 111 moves with respect to the fixed cylinder 140 along the optical axis of the optical system 101 together with the lens frame 112 and the first lens group 114 by a cam mechanism including the cam grooves 148 and 152 and the cam follower 116.

  The second lens group 124 is held by the middle cylinder 121 via the lens frame 122. The middle cylinder 121 holds the diaphragm device 162 and the vibration correction device 164 together to form an intermediate unit 160.

  The middle cylinder 121 moves along the optical axis of the optical system 101 with respect to the fixed cylinder 140 when the first movement assisting portion 161 and the U-shaped groove portion 163 are engaged with the guide bars 142 and 144 (see FIG. 4). To do. As a result, the lens frame 122 and the second lens group 124 held by the middle cylinder 121 also move along the guide bars 142 and 144.

  The third lens group 134 is held by the rear cylinder 135 via the lens frame 132. The rear cylinder 135 and the lens frame 132 form a rear group unit 130. The rear cylinder 135 also moves along the optical axis direction of the optical system 101 with respect to the fixed cylinder 140 when the second movement assisting part 131 engages with the guide bars 142 and 144. As a result, the lens frame 132 and the third lens group 134 held by the rear cylinder 135 also move along the guide bars 142 and 144.

  By moving these lens groups, the focal position, focal length, etc. of the optical system 101 change. The lens barrel 100 includes a cam barrel 150 as an element for driving the middle barrel 121 and the rear barrel 135. The cam cylinder 150 has cam grooves 152, 154 and 156.

  Further, the cam barrel 150 can rotate coaxially with the central axis of the fixed barrel 140 as the center of rotation by operating a zoom ring 151 provided on the outer periphery of the lens barrel 100. Further, the lens barrel 100 incorporates a microcomputer 170 in addition to these. The microcomputer 170 executes communication control when transmitting and receiving electrical signals to and from the outside of the lens barrel 100.

  FIG. 2 is a partial exploded perspective view of the lens barrel 100. The lens barrel 100 is disassembled into a cam barrel 150, a fixed barrel 140, an intermediate unit 160, a rear group unit 130, and guide bars 142 and 144 in order from the left side of the drawing corresponding to the front end side (object side) of the lens barrel 100. Is done. The front group unit 110 shown in FIG. 1 is not shown.

  The cam cylinder 150 is provided outside the fixed cylinder 140 in the state shown in FIG. When the lens barrel 100 is assembled, the fixed barrel 140 is inserted into the cam barrel 150 from the rear end side. The guide bars 142 and 144 are fixed to the fixed barrel 140, but can be pulled out to the rear side of the lens barrel 100 when the lens barrel 100 is assembled, as will be described later.

  The intermediate unit 160 and the rear group unit 130 are assembled by being inserted into the inner diameter side of the fixed cylinder 140. In other words, from the state shown in FIG. 1, the rear group unit 130 can be pulled out from the fixed barrel 140 to the rear end side of the lens barrel 100, and the intermediate unit 160 can be pulled from the fixed barrel 140 to the lens barrel. 100 can be pulled out to the front end side. Hereinafter, each element will be described individually.

  FIG. 3 is a perspective view showing the structure of the fixed cylinder 140. 3A shows a state in which the fixed barrel 140 is looked down from the obliquely rear side of the lens barrel 100. FIG. FIG. 3B shows a state in which the fixed barrel 140 is looked down from the oblique front side of the lens barrel 100.

  The fixed cylinder 140 has a cylindrical shape as a whole and includes guide bars 142 and 144, a cam groove 148 and a base 146. The base 146 is formed at the rear end of the fixed barrel 140, and a mount for fixing the lens barrel 100 to another member is attached.

  The guide bar 142 is fixed along the longitudinal direction of the fixed cylinder 140 inside a notch 141 formed on the upper surface of the fixed cylinder 140. Since the extending direction of the guide bar 142 and the optical axes of the second lens group 124 and the third lens group 134 are designed to be parallel to each other, the longitudinal direction of the fixed barrel 140 is also set to the second lens group 124 and the third lens group 134. The optical system 101 having the lens group 134 is parallel to the optical axis. The guide bar 144 is fixed along the longitudinal direction on the inner diameter side of the fixed cylinder 140.

  In the illustrated example, the shape of the guide bars 142 and 144 is a rod having a circular cross section. However, the shape of the guide bars 142 and 144 is not limited to this. That is, an arbitrary cross-sectional shape can be given as long as the intermediate unit 160 is a shape to which the intermediate unit 160 slides and moves.

  FIG. 6 is a perspective view and a rear view showing the structure of the intermediate unit 160. FIG. 6A is a perspective view showing a state in which the intermediate unit 160 is looked down from the obliquely rear side of the lens barrel 100. FIG. 6B is a rear view when the intermediate unit 160 is viewed from the rear of the lens barrel 100.

  As shown in FIG. 4A, a pair of first movement assisting portions 161 are provided along the extending direction of the guide bar 142. A plurality of the first movement assisting portions 161 may be provided along the extending direction of the guide bar 142. In the present embodiment, a V-shaped groove 167 that abuts against the guide bar 142 is formed on the upper surface of each of the first movement assisting portions 161 by a pair of abutting surfaces that face and intersect each other. Details of the V-shaped groove 167 will be described later.

  The cam follower 166 is disposed adjacent to the side of the first movement assisting portion 161 in a direction orthogonal to the extending direction of the guide bar 142 on the outer peripheral surface of the middle cylinder 121. Further, the cam follower 166 protrudes from the outer peripheral surface of the middle cylinder 121 along the radial direction.

  One end of a leaf spring 169 is fixed to the middle cylinder 121 in the vicinity of the cam follower 166. One surface of the other end of the leaf spring 169 contacts the guide bar 142. The leaf spring 169 attracts the first movement assisting portion 161 toward the guide bar 142 by the urging force of the leaf spring 169. Therefore, the V-shaped groove 167 and the guide bar 142 are in close contact with each other, and the V-shaped groove 167 is engaged with the guide bar 142.

  By providing a plurality of first movement assisting portions 161 and energizing them using the leaf springs 169, the inclination of the middle cylinder 121 with respect to the guide bar 142 is effectively suppressed. Therefore, the optical axis of the second lens group 124 is prevented from being inclined with respect to the longitudinal direction of the fixed cylinder 140.

  In the lens barrel 100, the first movement assisting portion 161 has a leaf spring 169 that urges one of the guide bar 142 and the V-shaped groove 167 toward the other, so that the first movement assisting portion 161 and the guide bar 142 The backlash between them is resolved autonomously and the movement of the intermediate unit 160 can be accurately guided. Further, in the radial direction of the middle cylinder 121, there is only a thin leaf spring 169 outside the guide bar 142. Therefore, the height of the cam follower 166 can be suppressed as compared with the case where the cam follower 166 is disposed on the outer peripheral side of the first movement assisting portion 161. Furthermore, it does not hinder when other members are arranged outside the middle cylinder 121.

  Further, as shown in FIG. 4B, the U-shaped groove portion 163 is engaged with the guide bar 144. That is, the U-shaped groove portion 163 sandwiches the side surface of the guide bar 144 from the circumferential direction of the middle cylinder 121 by a pair of contact surfaces parallel to each other. Thereby, it is possible to prevent the middle cylinder 121 from rotating around the guide bar 142 in a plane orthogonal to the optical axis of the second lens group 124.

  FIG. 5 is a perspective view and a rear view showing the structure of the rear group unit 130. FIG. 5A is a perspective view showing a state in which the rear cylinder 135 is looked down from the oblique front side of the lens barrel 100. FIG. 5B is a rear view when the rear tube 135 is viewed from the rear of the lens barrel 100.

  As with the middle cylinder 121, the rear cylinder 135 is provided with a second movement assist part 131, a cam follower 136, and a U-shaped groove part 133 on the outer peripheral surface thereof. Further, the rear cylinder 135 holds the third lens group 134 inside via the lens frame 132.

  As shown in FIG. 5A, a pair of second movement assisting portions 131 are provided along the extending direction of the guide bar 142. A V-shaped groove 137 that is formed by a pair of contact surfaces facing each other and that contacts the guide bar 142 is formed on each upper surface of the second movement assisting portion 131. In the lens barrel 100, the second movement assisting portion 131 has a V-shaped groove 137 that contacts the guide bar 142 and includes a plurality of surfaces facing each other, so that the optical axis of the third lens group 134 is the optical system 101. Deviation from the entire optical axis is prevented.

  The cam follower 136 is disposed adjacent to the second movement assisting part 131 on the outer peripheral surface of the rear cylinder 135. The cam follower 136 protrudes from the outer peripheral surface of the rear cylinder 135 in the radial direction of the rear cylinder 135.

  One end of a leaf spring 139 is fixed to the rear cylinder 135 in the vicinity of the cam follower 136. The other end of the leaf spring 139 contacts the guide bar 142. The second movement assisting part 131 is attracted toward the guide bar 142 by the urging force of the leaf spring 139. Therefore, the V-shaped groove 137 and the guide bar 142 are in close contact with each other. In the lens barrel 100, a plurality of second movement assisting portions 131 are provided along the extending direction of the guide bar 142. It can be effectively suppressed.

  As shown in FIG. 5B, the U-shaped groove 133 engages with the guide bar 144 at a position different from the second movement assisting portion 131. The U-shaped groove 163 sandwiches the side surface of the guide bar 144 from the circumferential direction of the rear cylinder 135 by a pair of contact surfaces parallel to each other. Thereby, it is possible to suppress the rear cylinder 135 from rotating around the guide bar 142 in the plane orthogonal to the optical axis of the third lens group 134.

  Moreover, the U-shaped groove part 133 is arrange | positioned away from the 2nd movement assistance part 131 about the circumferential direction. Therefore, rattling between the U-shaped groove part 133 and the guide bar 144 and between the second movement auxiliary part 131 and the guide bar 142 is efficiently suppressed, and the third lens group 134 is orthogonal to the optical axis. It can be accurately positioned in a plane.

  FIG. 6 is a perspective view showing how the intermediate unit 160 and the rear group unit 130 move in the assembly in which the intermediate unit 160 and the rear group unit 130 are assembled to the fixed cylinder 140. It should be noted that the same reference numerals are assigned to the same components as those in the other drawings, and redundant description is omitted.

  FIG. 6A shows a state in which the intermediate unit 160 and the rear group unit 130 are located on the rear end side of the lens barrel 100. Here, the guide bar 142 is fixed by cutting the notch 141 of the fixed cylinder 140 vertically. Further, the rear group unit 130 is inserted inside the fixed cylinder 140. The second movement assisting part 131 of the rear cylinder 135 is engaged with the guide bar 142. In addition, the cam follower 136 of the rear cylinder 135 protrudes from the fixed cylinder 140 through the notch 141.

  The intermediate unit 160 is accommodated further inside the rear cylinder 135. The first movement assisting part 161 and the cam follower 166 of the intermediate unit 160 are exposed to the outside through the notch part 138 of the rear cylinder 135 and the notch part 141 of the fixed cylinder 140.

  The first movement assisting portion 161 of the intermediate unit 160 is engaged with the guide bar 142. Further, the cam follower 166 of the middle cylinder 121 protrudes outside the fixed cylinder 140.

  On the other hand, since the leaf springs 169 and 139 of the intermediate unit 160 and the rear group unit 130 are both thin, they are within the thickness range of the fixed cylinder 140. Therefore, the leaf springs 169 and 139 do not protrude outward from the outer peripheral surface of the fixed cylinder 140.

  Here, the pair of cam followers 166 and 136 are located on the opposite sides of the guide bar 142 in the circumferential direction of the fixed tube 140. Therefore, even when the pair of cam followers 166 and 136 approach in the extending direction of the guide bar 142, they do not interfere with each other.

  FIG. 6B shows a state in which the intermediate unit 160 and the rear group unit 130 are located on the front end side of the lens barrel 100. Also in this case, since the pair of cam followers 166 and 136 are located on the opposite side with respect to the guide bar 142, they do not interfere with each other.

  As described above, the cam follower 166 of the intermediate unit 160 and the cam follower 136 of the rear group unit 130 are located on the opposite sides of the guide bar 142 in the circumferential direction of the fixed cylinder 140. Therefore, even when the pair of cam followers 166 and 136 approach in the extending direction of the guide bar 142, they do not interfere with each other. As a result, both the intermediate unit 160 and the rear group unit 130 are guided by the single guide bar 142, but the movement range of the intermediate unit 160 and the rear group unit 130 can be widened.

  FIG. 7 is a perspective view showing the shape of the cam cylinder 150. FIG. 7A is a perspective view showing a state in which the left side surface of the cam barrel 150 is viewed obliquely from the rear of the lens barrel 100. FIG. FIG. 7B is a perspective view showing a state in which the right side surface of the cam barrel 150 is viewed from an oblique rear side of the lens barrel 100.

  The cam cylinder 150 as a whole has a cylindrical shape in which an opening 158 is provided in a part of the peripheral surface. A plurality of cam grooves 152, 154, 156 with which the cam followers 116, 136, 166 are engaged are formed on the peripheral surface of the cam cylinder 150.

  A plurality of cam grooves 152 are formed on the front end side of the cam barrel 150 at equal intervals in the circumferential direction of the cam barrel 150. A single cam groove 156 is formed on the rear end side of the cam cylinder 150. Furthermore, another cam groove 154 is formed on the front side of the cam groove 156. The opening 158 is formed by removing an unnecessary portion of the cam cylinder 150 in a region where the two rear cam grooves 154 and 156 are not formed.

  FIG. 8 is a perspective view showing a state in which the cam cylinder 150 is assembled to the assembly shown in FIG. Also in this figure, the same reference numerals are given to the same constituent elements as those in the other figures, and redundant description will be omitted.

  The cam cylinder 150 is attached to the outside of the assembly in which the intermediate unit 160 and the rear group unit 130 are assembled to the fixed cylinder 140. Thereafter, the cam followers 166 and 136 are attached from the outside of the fixed cylinder 140 so as to engage with the cam grooves 154 and 156.

  The cam follower 166 of the intermediate unit 160 engages with a cam groove 154 in the middle of the cam cylinder 150. Further, the movement direction of the intermediate unit 160 is limited to the extending direction of the guide bar 142 by the first movement assisting portion 161. Therefore, when the cam cylinder 150 rotates around the optical axis of the optical system 101, the cam follower 166 pushed by the cam groove 154 moves along the optical axis direction of the lens barrel 100. Therefore, the second lens group 124 held by the middle cylinder 121 also moves along the optical axis direction.

  Similarly, the cam follower 136 of the rear cylinder 135 engages with the cam groove 156 on the rear end side of the cam cylinder 150. Further, the movement direction of the rear cylinder 135 is limited by the second movement auxiliary portion 131 to the extending direction of the guide bar 142. Therefore, when the cam cylinder 150 rotates around the optical axis of the optical system 101, the cam follower 136 pushed by the cam groove 156 moves along the optical axis direction of the lens barrel 100. Therefore, the third lens group 134 held by the rear cylinder 135 also moves along the optical axis direction.

  Thus, when the middle cylinder 121 is driven along the guide bar 142, the pressing force applied from the cam groove 154 to the cam follower 166 is substantially orthogonal to the direction in which the cam follower 166 protrudes from the middle cylinder 121. Thereby, the driving force can be efficiently transmitted to the middle cylinder 121 from the cam cylinder 150 rotating in a direction different from the moving direction of the middle cylinder 121.

  FIG. 9 is an enlarged view showing the arrangement of the cam follower 166 and the V-shaped groove 167 in the intermediate unit 160. In FIG. 9, a part of the intermediate unit 160 is omitted. In addition, the descriptions of “left” and “right” in the following description are described along the direction depicted in the figure, and limit the structure, orientation, etc. of the intermediate unit 160 or the intermediate cylinder 121. is not.

  The V-shaped groove 167 has a right side wall 182 and a left side wall 184 that are inclined. The V-shaped groove 167 further has a horizontal bottom surface 186. For this reason, the right side wall 182 and the left side wall 184 do not intersect directly, but if the surfaces including the right side wall 182 or the left side wall 184 are respectively extended, they intersect with an angle smaller than 90 degrees.

  One end of the leaf spring 169 is fixed to the middle cylinder 121. One surface of the other end of the leaf spring 169 abuts on the guide bar 142 and urges the center of the middle cylinder 121 toward the center of the guide bar 142. The urging force P acting on the guide bar 142 from the leaf spring 169 acts in the direction of a straight line N passing through the center C of the middle cylinder 121 and the center of the guide bar 142.

The cam follower 166 protrudes from the middle cylinder 121 in a direction along the straight line D including the diameter of the middle cylinder 121. Thereby, the pressing force applied from the cam groove 154 to the cam follower 166 is substantially orthogonal to the direction along the straight line D. When the cam cylinder 150 rotates about the same axis as the fixed cylinder 140, a pressing force is applied to the cam follower 166 from the cam groove 154, and the cam follower 166 moves in the longitudinal direction of the fixed cylinder 140 according to the shape of the cam groove 154. When the cam follower 166 moves in the longitudinal direction of the fixed cylinder 140, the middle cylinder 121 moves in the direction perpendicular to the paper surface of FIG. 9, and the second lens group 124 moves in the optical axis direction. Note that the cam follower 166 is disposed closer to the right side wall 182 than the left side wall 184.

  Here, when the cam cylinder 150 rotates, for example, counterclockwise with respect to the fixed cylinder 140, the cam groove 154 applies a pressing force F1 including a component from right to left to the cam follower 166. In addition, when the cam cylinder 150 rotates clockwise with respect to the fixed cylinder 140, the cam groove 154 applies a pressing force F2 including a component from the left to the right to the cam follower 166. A part of the cylindrical surface on which the pressing forces F <b> 1 and F <b> 2 act on the cam follower 166 is hereinafter referred to as a cam follower surface 168.

  When a pressing force F1 acts on the cam follower surface 168, a reaction force R1 is generated on the right side wall 182 due to the pressing force F1 and the urging force P. On the other hand, when the pressing force F <b> 2 acts on the cam follower 166, a reaction force R <b> 2 with respect to the pressing force F <b> 2 and the urging force P is generated on the left side wall 184.

  Here, at the contact portion between the right side wall 182 and the guide bar 142, a component force f1 is generated to push the V-shaped groove 167, that is, the intermediate unit 160 downward with respect to the guide bar 142 by the pressing force F1. By appropriately setting the combination of the friction coefficient of the contact portion between the wall 182 and the guide bar 142 and the angle α of the right side wall 182, the frictional force μR1 is increased. The V-shaped groove 167, that is, the intermediate unit 160 is not moved downward.

  Similarly, when a pressing force F2 acts on the cam follower 166, a reaction force R2 is generated on the left side wall 184 due to the pressing force F2 and the urging force P.

  Here, at the contact portion between the left side wall 184 and the guide bar 142, a component force f2 is generated to push the V-shaped groove 167, that is, the intermediate unit 160 downward with respect to the guide bar 142 by the pressing force F2. By appropriately setting the combination of the friction coefficient of the contact portion between the wall 184 and the guide bar 142 and the angle α of the left side wall 184, the frictional force μR2 is increased. The V-shaped groove 167, that is, the intermediate unit 160 is not moved downward.

  In this embodiment, the urging force P urges the guide bar 142 toward the center of the optical axis, but the reaction force required at the contact portion between the left and right side walls 182 and 184 of the V-shaped groove 167 and the guide bar 142. If it can generate | occur | produce, it does not necessarily need to urge in the optical axis center direction.

  Here, the inclination direction of the V-shaped groove 167 may be substantially parallel to the direction in which the cam follower 166 protrudes from the middle cylinder 121. However, even if it is not strictly parallel, as long as the inclination of the V-shaped groove 167 is inclined toward the cam follower 166, the effect of suppressing the middle cylinder 121 from being shifted downward relative to the guide bar 142. There is.

Accordingly, the V-shaped groove 167 is prevented from being detached from the guide bar 142 due to the reaction force R2 when the cam follower 166 is driven .

  FIG. 10 is a diagram schematically illustrating the structure of the imaging apparatus 300 including the lens barrel 100. In FIG. 10, the lens barrel 100 is schematically shown for the purpose of avoiding complicated drawing. However, the lens barrel 100 in FIG. 10 has the same structure as the lens barrel 100 shown in FIG. Therefore, the same components are denoted by the same reference numerals, and redundant description is omitted.

  The lens barrel 100 is detachably attached to the imaging unit 200 via the mount unit 260. In the imaging apparatus 300, the lens barrel 100 and the imaging unit 200 are also electrically coupled via a connection terminal (not shown). Thereby, the lens barrel 100 is supplied with power from the imaging unit 200. Further, the microcomputer 170 of the lens barrel 100 and the main control unit 250 of the imaging unit 200 exchange information with each other.

  The imaging unit 200 houses an optical system including a main mirror 240, a pentaprism 270, and an eyepiece optical system 290, and a main control unit 250. The primary mirror 240 has a standby position that is inclined on the optical path of incident light incident through the optical system 101 of the lens barrel 100, and a photographing position that rises while avoiding the incident light (shown by a dotted line in the figure). ).

  The primary mirror 240 in the standby position guides most of the incident light to the focusing screen 272 disposed above. The focusing screen 272 is disposed at a focus position of the optical system 101 of the lens barrel 100 and forms an image formed by the optical system 101.

  The image formed on the focusing screen 272 is observed from the eyepiece optical system 290 via the pentaprism 270. As a result, the image on the focusing screen 272 can be viewed as a normal image from the eyepiece optical system 290.

  Between the pentaprism 270 and the eyepiece optical system 290, a half mirror 292 that superimposes the display image formed on the finder LCD 294 on the image of the focusing screen 272 is disposed. Thereby, at the exit end of the eyepiece optical system 290, the image on the focusing screen 272 and the image on the finder LCD 294 can be seen together. Note that information such as shooting conditions and setting conditions of the imaging apparatus 300 is displayed on the finder LCD 294.

  A part of the light emitted from the pentaprism 270 is guided to the photometry unit 280. The photometry unit 280 measures the intensity of incident light, its distribution, and the like, and refers to the measurement result when determining imaging conditions.

  On the other hand, a secondary mirror 242 is disposed on the back surface of the primary mirror 240 with respect to the incident light incident surface. The secondary mirror 242 guides part of the incident light transmitted through the primary mirror 240 to the focus detection device 230 disposed below. Thereby, when the primary mirror 240 is in the standby position, the focus detection device 230 detects the focus adjustment state of the optical system 101. When the primary mirror 240 is moved to the photographing position, the secondary mirror 242 is also retracted from the optical path of the incident light.

  A shutter 220, an optical filter 212, and an image sensor 210 are arranged along the optical axis behind the main mirror 240 with respect to the incident light from the lens barrel 100. When the shutter 220 is opened, the primary mirror 240 moves to the photographing position immediately before that, so that the incident light travels straight and enters the image sensor 210. As a result, the image formed by the incident light is converted into an electrical signal in the image sensor 210.

  In addition, the imaging unit 200 includes a main LCD 296 facing the outside on the rear surface with respect to the lens barrel 100. The main LCD 296 can display various setting information for the image capturing unit 200 and can display an image formed on the image sensor 210 when the primary mirror 240 is moved to the photographing position.

  The main control unit 250 comprehensively controls the various operations as described above. In addition, an autofocus mechanism that drives the lens barrel 100 can be formed by referring to information on the distance to the subject detected by the focus detection device 230 on the imaging unit 200 side. Furthermore, the focus detection device 230 can form a focus aid mechanism by referring to the operation amount of the lens barrel 100.

  Further, the main control unit 250 exchanges information with the microcomputer 170 of the lens barrel 100 to control opening / closing of the diaphragm device 162 and the like. Further, the main control unit 250 contributes to automating exposure, execution of a scene mode, execution of bracket photography, and the like. In this manner, the imaging apparatus 300 including the lens barrel 100 described above and the imaging unit 200 that captures an image formed using the lens barrel 100 is formed.

  An imaging device 300 is formed that includes the lens barrel 100 and an imaging unit 200 that captures an image by the optical system 101 including the first lens group 114, the second lens group 124, and the third lens group 134. Thus, the lens barrel 100 having the structure shown in FIG. 1 can be suitably used in the imaging apparatus 300. However, the use of the lens barrel 100 is not limited to this, and can be used for a focusing mechanism, a zoom mechanism, and the like in an optical system such as a motion picture camera, binoculars, a microscope, and a surveying instrument.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. In addition, it will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. Furthermore, it is apparent from the description of the scope of claims that the embodiments added with changes or improvements can be included in the technical scope of the present invention.

2 is a cross-sectional view of the entire lens barrel 100. FIG. 2 is an exploded perspective view of the entire lens barrel 100. FIG. 4 is a perspective view showing a structure of a fixed cylinder 140. FIG. FIG. 6 is a perspective view and a rear view showing the structure of the intermediate unit 160. It is the perspective view and back view which show the structure of the rear group unit 130 of the 3rd group. FIG. 6 is a perspective view showing the movement of the intermediate unit 160 and the rear group unit 130. 3 is a perspective view showing the shape of a cam cylinder 150. FIG. It is a perspective view which shows the state which assembled | attached the cam cylinder 150 to the assembly shown in FIG. It is a figure explaining arrangement of cam follower 166 and V-shaped groove 167. 2 is a diagram schematically showing the structure of an imaging apparatus 300. FIG.

Explanation of symbols

100 lens barrel, 101 optical system, 110 front group unit, 130 rear group unit, 111 front cylinder, 112, 122, 132 lens frame, 114 first lens group, 116, 136, 166 cam follower, 121 middle cylinder, 124 first 2 lens group, 129 connecting portion, 131 second movement assisting portion, 133, 163 U-shaped groove, 134 third lens group, 135 rear tube, 137, 167 V-shaped groove, 138, 141, 158 notched portion, 139, 169 leaf spring, 140 fixed cylinder, 142, 144 guide bar, 146 base, 148, 152, 154, 156 cam groove, 150 cam cylinder, 151 zoom ring, 160 intermediate unit, 161 first movement auxiliary section, 162 aperture device, 164 vibration correction device, 168 cam follower surface, 170 microcomputer, 182 right side wall, 18 Left side wall, 186 bottom surface, 200 imaging unit, 210 imaging device, 212 optical filter, 220 shutter, 230 focus detection device, 240 primary mirror, 242 secondary mirror, 250 main control unit, 260 mount unit, 270 pentaprism, 272 focusing screen 280 Photometry unit, 290 Eyepiece optical system, 292 Half mirror, 294 Finder LCD, 296 Main LCD, 300 Imaging device

Claims (7)

A shaft member provided in the fixed portion;
A lens holding member that has a groove portion that includes a first surface and a second surface that are in contact with and intersect each other, and that is movable along the shaft member while holding the lens;
A driving member for driving the lens holding member along the shaft member;
An engagement portion that engages with the drive member and is disposed closer to the first surface than the second surface on the peripheral surface of the lens holding member, and the groove portion is inclined toward the engagement portion side. Lens barrel. The lens barrel according to claim 1, wherein the lens holding member has a biasing member that biases the shaft member toward the first surface and the second surface.   3. The lens barrel according to claim 1, wherein an inclination direction of the groove portion is substantially parallel to a direction in which the engagement portion protrudes from the lens holding member. The lens barrel according to any one of claims 1 to 3, wherein the engaging portion protrudes from the lens holding member along a radial direction of the lens. When the lens holding member is driven along the shaft member, the pressing force applied from the driving member to the engaging portion is substantially orthogonal to the direction in which the engaging portion protrudes from the lens holding member. The lens barrel according to any one of claims 1 to 4. The lens barrel according to any one of claims 1 to 5, wherein the shaft member has a rod shape with a circular cross section. The lens barrel according to any one of claims 1 to 6,
An imaging unit that captures an image formed using the lens barrel;
An imaging apparatus having

Images