JPH09281376A - Lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To confirm a photographing distance to a subject without increasing production cost by providing a manual focusing operation ring with a different shape part whose shape is different from other surface and expressing the photographing distance to the subject according to the position in the rotating direction of the different shape part. SOLUTION: By rotating the MF operation ring 7 around an optical axis, the rotational motion is converted into straight advance motion in an optical axis direction in a male helicoid and a female helicoid, so that the ring 7 is moved back and forth in the optical axis direction so as to perform focusing. Since the ring 7 is provided with grooves 7d, 7e and 7f having the shape which can be discriminated from other parts at positions corresponding to the specified photographing distance on the outer peripheral surface of the ring 7, the distance at that time is confirmed by observing the positional relation among an attaching/detaching index 2e, a zooming index 2f and the grooves 7d, 7e and 7f. Thus, the space for the ring 7 is effectively utilized and the compact and inexpensive lens barrel is obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens barrel capable of confirming a shooting distance to a subject.

[0002]

2. Description of the Related Art In recent years, lens barrels that do not have a distance scale indicating a shooting distance to a subject have been increasing for convenience of a product concept or reduction of manufacturing cost. FIG.
FIG. 7 is a top view showing an example of such a lens barrel, and FIG. 7 is a front view of the lens barrel viewed from the front of the optical axis. In the figure, 101 is a mount, and the mount 101
A fixed cylinder 102 is installed in the. An attachment / detachment index 109 is printed on the outer peripheral surface of the fixed cylinder 102. The attachment / detachment index 109 is a mark indicating the correct position of the lens barrel when attaching / detaching the lens barrel to / from the camera body (not shown).

Further, a zoom ring 103 is installed on the outer peripheral surface of the fixed barrel 102 so as to be rotatable around the optical axis. Further, the rubber ring 10 is provided on the outer peripheral surface of the zoom ring 103.
4 is provided and the zoom scale 107 is printed. The rubber ring 104 facilitates the rotating operation of the zoom ring 103. On the other hand, the zoom scale 107
Indicates the focal length of the optical system at that time by being indicated by the zoom index 108 printed on the outer peripheral surface of the fixed barrel 102.

On the front side of the optical axis of the zoom ring 103, a manual focus operation ring (hereinafter referred to as "MF operation ring") 1
06 is installed. The MF operation ring 106 is a lens holding frame that holds the focusing lens 110 on the inner peripheral side thereof. The MF operation ring 106 moves the focusing lens 110 back and forth in the optical axis direction by performing a rotational rectilinear movement. On the outer peripheral surface of the MF operation ring 106, the knurl 1
06b is processed, which allows the MF operation ring 106 to be processed.
Prevents slipping of the hand when operating the.

As described at the beginning, the conventional lens barrel shown here does not have a distance scale for displaying the photographing distance. Therefore, in this conventional lens barrel, the manufacturing cost can be reduced because the process of printing the distance scale on the lens barrel is omitted. In addition, the MF operation ring 106, on which the distance scale is generally printed, has a compact shape in the optical axis direction as much as the photographing scale is omitted. As a result, the inertia of the MF operation ring 106 is reduced, and for example, the structure is such that it is easy to realize a recent product concept of rapid autofocus.

[0006]

However, in the above-mentioned conventional lens barrel, it is impossible to know the shooting distance at that time from the appearance of the lens barrel. Therefore, the shooting distance must be adjusted manually in advance. However, there is a problem in that it is impossible to perform so-called in-place pin photography, that is, photographing after that. Further, in the case of performing flash photography, there is a problem in that even if the dimming range up to the subject is instructed, it is not possible to determine whether the shooting distance at that time is within or outside the instructed dimming range. Further, in the inspection at the time of manufacturing, there is a problem that it is very difficult to perform the projection inspection because there is no distance scale.

Therefore, an object of the present invention is to provide a lens barrel capable of confirming the shooting distance to a subject without increasing the manufacturing cost and the like.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 provides a deformed portion having a shape different from other surfaces at one or more parts of a manual focus operation ring (7). (7d to 7i), and the photographing distance to the subject is represented by the rotational direction position of the odd-shaped portion. According to a second aspect of the present invention, in the lens barrel according to the first aspect, the manual focus operation ring has a non-slip notch (7c) on a surface thereof, and the deformed portion has the notch. It is characterized by being provided inside. According to a third aspect of the invention, in the lens barrel according to the first aspect, at least one of the deformed portions is provided at a position corresponding to the photographing distance related to the inspection of the optical system. And The invention according to claim 4 is the lens barrel according to claim 1 or 2, wherein the deformed portion is integrally formed with the manual focus operation ring.

[0009]

Hereinafter, an embodiment of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a top view of a lens barrel according to the present invention. Also,
FIG. 2 is a front view of the lens barrel, and FIG. 3 is a sectional view. The configuration of this embodiment will be described below mainly with reference to FIG.

In FIG. 3, reference numeral 1 denotes a male fixed mount having a bayonet 1a on its outer peripheral surface. In this embodiment, the fixed mount 1 is attached to a female mount of a camera body (not shown) to be attached to the camera body. The fixed portion 2 is a cylindrical member integrally installed on the fixed mount 1 on the optical axis front side of the fixed mount 1. The fixed portion 2 has three straight advance key portions 2a having a convex shape on the inner peripheral surface thereof. Further, two kinds of guide grooves 2b and 2c are provided around the optical axis on the outer peripheral surface of the fixed portion 2. The guide groove 2b is for guiding a zooming ring 3 described later, and is a groove extending in a range corresponding to a rotation angle of the zooming ring 3. The guide groove 2c is for mounting a drive ring 8 described later.

An attachment / detachment index 2e and a zoom index 2f are provided on the outer peripheral surface of the fixed portion 2 (FIG. 1). Detachable index 2
e is an index for determining the rotational direction position around the optical axis when the present embodiment is attached to or detached from the camera body. The zoom index 2f is an index for instructing a zoom scale 30 described later.

Reference numeral 3 denotes a zoom ring which is rotated from the outside when the focal length is adjusted in this embodiment. Zoom ring 3
Is provided with three pins 3a that are convex in the optical axis direction at the rear end of the inner peripheral surface. The pin 3a has a guide groove 2
The zoom ring 3 is attached to the fixed portion 2 so as to be rotatable around the optical axis. Also,
The zoom ring 3 includes a straight key portion 3b that is convex in the optical axis direction at the front end portion of the inner peripheral surface, and engages with a cam ring 5 to be described later via the straight key portion 3b. Further, the zoom ring 3 has a zoom scale 3c printed on the outer peripheral surface (FIG. 1). The zoom scale 3c is arranged in the circumferential direction and is composed of a plurality of numerical values. Among these numerical values, the numerical value designated by the zoom index 2f represents the focal length at that time.

Reference numeral 5 denotes a cam ring, which has a cam groove 5d defining the position of the lens unit L3 in the optical axis direction on the inner peripheral side thereof. The cam ring 5 has a straight guide groove 5a and a male helicoid screw 5b at the center of the outer peripheral surface, and a cam projection 5c at the front end of the outer peripheral surface. The straight-ahead guide groove 5a is engaged with the straight-ahead key portion 3b of the zoom ring 3. Therefore, the cam ring 5 rotates together with the zoom ring 3.

The adjusting member 4 arranged on the outer peripheral side of the cam ring 5 is a member used for adjusting the optical system after the assembly of this embodiment is completed. A female helicoid screw 4 a is provided on the inner peripheral surface of the adjusting member 4. The female helicoid screw 4a is the male helicoid screw 5 of the cam ring 5.
b. Therefore, when the adjusting member 4 is rotated, the cam ring 5 moves back and forth in the optical axis direction.

The male helicoid member 6 is a member for moving the focusing lens unit L1 in the optical axis direction together with the cam ring 5 and the MF operation ring 7 described later. The male helicoid member 6 is provided with cam followers 6b and 6c which engage with the cam projection 5c on the inner peripheral surface thereof. Further, the male helicoid member 6 has a straight guide groove 6d on the outer peripheral surface thereof. The linear guide groove 6d is engaged with the linear key 2a,
For this reason, the male helicoid member 6 does not rotate about the optical axis. Further, the male helicoid member 6 is provided with a male helicoid 6a on the outer peripheral surface of the front end portion thereof, through which M
It is engaged with the F operation ring 7.

The MF operation ring 7 is a holding frame for the focusing lens unit L1. The MF operation ring 7 has a female helicoid 7a on the inner peripheral surface and a key portion 7b on the rear end portion of the outer peripheral surface. Here, the female helicoid 7a is engaged with the male helicoid 6a. Therefore, when the MF operating ring 7 is rotated, the MF operating ring 7 also moves in the optical axis direction, and as a result, the position of the focusing lens unit L1 in the optical axis direction is adjusted.

The outer peripheral surface of the MF operating ring 7 is knurled. The knurled 7c has a curved bottom (R
A plurality of V-shaped grooves, which are surfaces, are provided (see FIG. 2). In principle, all the grooves of the knurling have the same length in the optical axis direction, but only the grooves 7d to 7i are processed shorter than the other grooves, and the deformed portion is visually distinguishable from the other grooves. (See FIG. 1).

The grooves 7d to 7i fulfill the function of the distance scale in the conventional lens barrel, that is, the function of indicating the photographing distance to the focused subject as a result of rotating the MF operating ring 7. Is. In the case of this embodiment, the groove 7d is provided at a position where an infinite (∞) scale was printed on the conventional distance scale.
Further, the grooves 7e to 7i are 7m, 5m, 3m, and 1 respectively.
m and the nearest scale are provided at the position where they were printed. That is, each of the grooves 7d to 7i is provided on the outer peripheral surface of the MF operation ring and at a position corresponding to a specific shooting distance. Thus, in the present embodiment, the shooting distance is set to infinity when the groove 7d is located on the straight line defined by the attachment / detachment index 2e and the zoom index 2f, as shown in FIG. 1, for example. Is shown. In this embodiment, the MF operation ring 7 is manufactured by injection molding of synthetic resin. Therefore, the grooves 7d to 7i are integrally formed with the MF operation ring 7 without providing a special processing stroke.

The drive ring 8 is an annular member that receives power from a power source (not shown) via a gear portion 8b provided at the rear end portion of the inner peripheral surface and makes a rotary motion about the optical axis. . A key portion 8a extending in the optical axis direction is provided at the front end portion of the drive ring 8, and the key portion 8a controls the key portion 7b of the MF operation ring 7 so that only relative movement in the optical axis direction is possible. I am combining. Therefore, the drive ring 8 and the MF operation ring 7 are integrated in the rotational direction, and the position of the focusing lens unit L1 in the optical axis direction is adjusted by rotationally driving the drive ring 8 using the power source described above. Is possible.

The holding member 11 is a member for holding the lens unit L3. The holding member 11 includes a guide groove 11b and an interlocking protrusion 11a on the outer peripheral surface. The guide groove 11b is a groove portion that engages with the straight advancement interlocking key 10. Straight advance interlocking key 10
Is a key member that is fixed to the fixing portion 2 with screws 12 and extends in the optical axis direction. The holding member 11 is movable only in the optical axis direction because the guide groove 11b and the straight-movement interlocking key 10 are engaged with each other. On the other hand, the interlocking protrusion 11a is a protrusion that is engaged with the cam groove 5d. When the cam ring 5 rotates, the interlocking protrusion 11a moves back and forth in the optical axis direction along the cam groove 5d, whereby the position of the holding member 11 in the optical axis direction is adjusted.

The holding member 50 is a member for holding the lens unit L2, and is provided with an escape groove for escaping the rectilinear interlocking k-10 on its outer peripheral surface. The adhesive tape 15 is for integrally bonding the zoom ring 3 and the adjusting member 4 in the rotation direction around the optical axis. The rubber ring 20 is a member that covers the outer peripheral surfaces of the zoom ring 3 and the adjusting member 4 and is fixed to them with an adhesive tape 15.

Next, the operation of this embodiment will be described.
When the zoom ring 3 is rotated around the optical axis, the adjusting member 4 and the cam ring 5, which are integrated with the zoom ring 3 in the rotation direction, rotate around the optical axis. The rotational movement of the cam ring 5 is converted into a rectilinear movement in the optical axis direction by the cam projection 5c and the cam followers 6b and 6c, and is transmitted to the male helicoid member 6. Therefore, the male helicoid member 6 moves back and forth in the optical axis direction along the cam protrusion 5c. At the same time, male helicoid 6
The MF operation ring 7 that is screwed to the MF operation ring 7 also moves back and forth in the optical axis direction. As a result, the focused state of the optical system is kept constant regardless of the operation of the zoom ring 3.

The rotational movement of the cam ring 5 is caused by the cam groove 5d.
Also, the interlocking protrusion 11a is also converted into movement in the optical axis direction. Therefore, when the cam ring 5 rotates, the holding member 1
1 moves back and forth along the cam groove 5d in the optical axis direction, so-called zooming is performed.

On the other hand, by external operation or by transmitting power from a power source (not shown) through the drive ring 8, M
When the F operation ring 7 is rotated around the optical axis, the rotational movement is generated in the male helicoid 6a and the female helicoid 7a.
It is converted into a rectilinear motion along the optical axis. As a result, the MF operation ring 7 moves back and forth in the optical axis direction, and the optical system in this embodiment is focused.

Next, the case where the flange back adjustment is performed in this embodiment will be described. The flange back is the distance from the surface of the flange of the lens barrel that is closely fixed to the camera body to the focal plane of the image to be captured. Generally, in a zoom lens barrel, there is an error in the focal position of the optical system due to variations in the accuracy of each component. In order to eliminate such an error, the position of the focusing lens (focusing lens unit L1 in the present embodiment) in the optical axis direction is finely adjusted using a washer or the rotation limit position is shifted. As a result, the focus is adjusted so as not to occur between the wide side and the tele side. However, if the above adjustment is performed, the flange back of the entire optical system changes, so that the flange back adjustment must be performed after that.

In this embodiment, the flange back adjustment is performed after the lens barrel is assembled and before the adjustment member is fixed to the zoom ring 3 or the like by the adhesive tape 15.
It is performed by rotating. In this embodiment,
When the zoom ring 3 is fixed in the rotational direction because the straight guide groove 3a of the cam ring 3 and the straight key portion 3b of the zoom ring 3 are engaged, the cam ring 5 moves in the optical axis direction. Only go straight. Therefore, when the adjusting member 4 is rotationally operated, the rotational movement thereof is converted into a linear movement in the optical axis direction by the female helicoid 4a and the male helicoid 5b and transmitted to the cam ring 5. As a result, the cam ring 5 moves in the optical axis direction according to the rotation amount of the adjusting member 4, and the flange back is adjusted.

Next, a method for confirming whether or not the photographing distance is within the light control range when stroboscopic photography is performed using this embodiment will be described. For example, the dimming range is 3m-7m
In the case of, the knurls 7c included in the MF operation ring 7 have grooves 7g and 7m corresponding to a shooting distance of 3m.
The appropriateness of the shooting distance is confirmed using the groove 7e corresponding to.
That is, when the area on the MF operation ring 7 sandwiched between the grooves 7g and 7e is located on the straight line defined by the attachment / detachment index 2e and the zoom index 2f, the shooting distance is 3 m to 7 m.
It is confirmed that within the range, that is, the shooting distance is within the light control range.

As described above, in this embodiment, M
Grooves (7d to 7d) having a shape identifiable from other parts are formed on the outer peripheral surface of the F operation ring 7 at a position corresponding to a specific shooting distance.
i) is provided. Therefore, in the present embodiment, it is possible to confirm the shooting distance at that time by looking at the positional relationship between the attachment / detachment index 2e and the zoom index 2f and the grooves 7d to 7i.

Further, in this embodiment, the MF operation ring 7 and the grooves 7d to 7i are integrally machined by injection molding of synthetic resin.
It is supposed to be produced. Therefore, the groove 7 is formed in the MF operation ring 7.
In order to provide d to 7i, it is not necessary to introduce a printing process, which is required in the conventional distance scale, for example. As a result, the lens barrel of the present embodiment can be produced at low cost without increasing the production cost or lowering the production efficiency, as compared with the conventional lens barrel having no distance scale or the like. It is possible.

Further, since the groove 7d and the like are not provided by printing unlike the conventional distance scale, it is not necessary to secure a space for printing in the MF operating ring 7, and the MF operating ring 7 can be made compact. It can be manufactured. In particular, in this embodiment, the groove 7d and the like are formed on the knurl 7c.
Since it is provided inside, the narrow space on the MF operation ring is effectively used, and its compactness is effectively realized. As a result, the present embodiment makes it possible to provide a lens barrel that is an MF operation ring with small inertia that enables rapid autofocusing and the like, and that is capable of confirming the shooting distance. The grooves 7d and the like are much more excellent in durability such as abrasion resistance as compared with the scale provided by printing, and there is an effect that their identification does not become difficult after long-term use. .

(Other Embodiments) The present invention is not limited to the above embodiment. The above embodiment is an exemplification, and has substantially the same configuration as the technical idea described in the scope of the claims of the present invention. It is included in the technical scope of the invention.

For example, in the above-described embodiment, the groove 7d or the like is provided as the deformed portion of the MF operation ring indicating the shooting distance, but the deformed portion may have another shape if its position can be visually identified. It may be one. 4 and 5 are a top view and a front view of such another example. As shown in FIGS. 4 and 5, the deformed portion may be a protrusion provided on the outer peripheral surface of the MF operation ring, and in addition, a V-shaped protrusion, a V-shaped groove, Further, it may be a square groove or the like.

Further, in the above embodiment, the grooves 7d to 7d are formed.
One of i is 30f (30
It may be provided at a position on the MF operation ring 7 corresponding to (X focal length). This shooting distance is a shooting distance used in the projection inspection at the time of manufacturing, and the projection inspection can be efficiently performed if a deformed portion representing the shooting distance is provided.

[0034]

As described above in detail, according to the invention of claim 1, one or more portions of the manual focus operation ring are provided with a deformed portion having a shape different from other surfaces. It is possible to check the shooting distance,
It is possible to provide a compact lens barrel.
According to the invention of claim 2, since the deformed portion is provided in the non-slip notch of the manual focus operation ring, the space of the manual focus operation ring is effectively used to make a compact shape. It is possible to provide a lens barrel.

According to the invention of claim 3, at least one of the deformed portions is provided at a position corresponding to a photographing distance related to the inspection of the optical system. Therefore, the inspection of the lens barrel can be performed efficiently. It is possible. According to the invention of claim 4, since the deformed portion is integrally formed with the manual focus operation ring, it is possible to provide an inexpensive lens barrel.

[Brief description of drawings]

FIG. 1 is a top view showing a lens barrel according to the present invention.

FIG. 2 is a front view of the lens barrel shown in FIG.

FIG. 3 is a cross-sectional view of the lens barrel shown in FIG.

FIG. 4 is a top view of a lens barrel according to the present invention, which is different from the lens barrel shown in FIG.

5 is a front view of the lens barrel shown in FIG.

FIG. 6 is a top view showing an example of a conventional lens barrel.

7 is a front view of the lens barrel shown in FIG.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Fixed mount 2 Fixed part 2e Attachment / detachment index 2f Zoom index 3 Zooming ring 4 Adjustment member 4 7 MF operation ring 7c Knurled 7d-7i Groove

Claims (4)

[Claims] 1. A manual focus operation ring 1 or 2
A lens barrel, comprising: a deformed portion having a shape different from that of the other surface in the above-mentioned portion, and a shooting distance to a subject is represented by a rotational direction position of the deformed portion. 2. The lens barrel according to claim 1, wherein the manual focus operation ring has a non-slip knurl on its surface, and the deformed portion is provided in the knurl. , A lens barrel characterized by the following. 3. The lens barrel according to claim 1 or 2, wherein at least one of the deformed portions is provided at a position corresponding to the photographing distance related to inspection of an optical system. Lens barrel characterized by. 4. One of claims 1 to 3
Item 10. The lens barrel according to item 4, wherein the deformed portion is integrally formed with the manual focus operation ring.