JPH0682880A - Lens hood - Google Patents

Abstract

PURPOSE:To prevent harmful light from being made incident from all areas of a zoom lens or out of a required region by slidably attaching a light shielding plate to a hood main body. CONSTITUTION:The light shielding plate 7 is slid in an axial direction by a position where the zoom lens is used and an elastic projection part 7a is restrained by the click part of the guiding groove 6g of the hood main body 6, so that the harmful light of a focal distance specified (a telephoto side position than a widest angle) by the click part can be prevented from being made incident. On the other hand, when the hood main body 6 is rotated with respect to a hood bayonet member 2, the click groove 6g is restrained at the position of a click ball 5 and the position of the light shielding plate 7 normally located just above can be changed so that the harmful light not only from a right above position but also a diagonal position, the side, etc., can be prevented from being made incident.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens hood detachably mounted on a lens barrel of a camera.

Further, the present invention relates to a lens hood which can be set to a hood having an optimum length according to an angle of view which changes due to zooming.

[0003]

2. Description of the Related Art Conventionally, the length of a light-shielding cylinder of a lens hood for an interchangeable lens, particularly a lens hood for a zoom lens including a wide-angle range (focal length wider than 35 mm), is determined by an incident light flux having the widest-angle focal length. It is set to a length that cannot be broken.

Further, the tightening knob system for attaching the lens hood is a lens hood for a telephoto system lens which is mounted by rotating the tightening knob, and a protrusion member provided on the hood cylinder and the inner circumference of the hood is made of resin. The ones that are configured are proposed.

Conventionally, there are two types of hoods for zoom lenses, one attached to the lens barrel as an accessory accessory to the lens for use, and the other incorporated in the lens barrel in advance. It was determined by the angle of view on the wide-angle side of the zoom lens. Further, in order to change the length and angle of the hood according to the change of the angle of view due to zooming, (a) German Patent No. 8020870 is configured so that the hood frame moves forward and backward in the optical axis direction in conjunction with zooming. ing. (B) In Japanese Utility Model Laid-Open No. 58-108445, the angle of the hood with respect to the optical axis changes in accordance with zooming. (C) In Japanese Utility Model Publication No. 2-33222, a hood made of a flexible material is folded and used in an appropriate length according to the focal length.

[0006]

However, in the above-mentioned conventional example, the length of the light-shielding tube of the lens hood is very short, and when the zoom lens is used at a focal length longer than the maximum wide-angle focal length, Since the incident light beam angle becomes loose, an extra light beam is incident, and there is a problem that the harmful light, which is originally the function of the hood, cannot be cut.

On the other hand, the recent zoom lens adopts an optical system in which the first group lens closest to the subject is largely extended on the telephoto side in order to increase the zoom ratio by reducing the size on the wide angle side to improve portability. I often do it.

In that case, the mounting portion of the hood is provided on the holding frame for holding the first lens group. However, when zooming to the telephoto side, the hood is largely extended together with the holding frame for holding the first lens group. The hood must be extended according to the change in the angle of view due to changing to the telephoto end.

Therefore, in the above-mentioned conventional example, since the transmission mechanism for converting the movement of zooming into the movement of the hood transmits the movement of the zooming in the optical axis direction to the hood, the first lens group largely moves by the zooming recently. I couldn't adapt it to my zoom lens.

Further, since the hood barrel and the protruding member on the inner circumference of the hood barrel are made of resin, the weight of the entire lens hood can be reduced, and the camera can be operated when the lens hood is mounted on the tip of the lens barrel for photographing. However, the hood cylinder and the inner peripheral protrusion are made of resin. There was a problem. 1) Since the elasticity is greater than that of the conventional metal lens hood, when the tightening knob is rotated and tightened to attach it to the lens barrel, the tightening knob part and the facing part of the hood cylinder are tightened, When the 90 ° direction portion is deformed toward the inner peripheral side with respect to the knob portion, a clear feel of completion of tightening of the knob cannot be obtained. 2) Environment (temperature) compared to conventional metal lens hoods
Since the expansion and contraction rates are large with respect to changes, it is more difficult to remove than the lens barrel because the protruding member inside the hood barrel contracts when detaching from the lens barrel, especially at low temperatures. There were problems such as.

Further, in the conventional examples of (a) and (b), the apparatus is complicated and large in size, and is not suitable for a small zoom lens. Further, in the conventional example of (c), although it is simple, the length of the hood is changed depending on the folding position of the hood, so that it is difficult to make it an arbitrary length, and operability is also difficult.

An object of the present invention is to provide a lens hood that solves the above-mentioned conventional problems.

[0013]

The present invention is a lens hood having the following structure. (1) A hood bayonet member that is bayonet-coupled to a lens barrel front frame, and is rotatable with respect to this hood bayonet member, and
The zoom lens to be used is provided with a hood main body attached so that it can be locked at an appropriate position and a light shielding plate attached to the hood main body that is slidable in the optical axis direction and can be locked at an appropriate position. It is possible to obtain a hood effect that can block harmful light over the entire area or necessary area. (2) A first lens closest to a subject that moves by zooming, and a hood feeding device in which a rotation amount of the built-in hood about an optical axis and a feeding amount of the hood with respect to the first lens have a predetermined relationship. A hood rotation transmission shaft arranged in parallel with an optical axis for transmitting a rotational force to a pinion gear that meshes with a spur gear provided on the inner circumference of the hood, and an optimum hood extension amount according to an angle of view changed by zooming. By providing the connecting means for rotating the hood rotation transmission shaft in association with the member rotated by the zooming means, the zooming force can be transmitted to the hood even for a zoom lens of a type in which the entire lens length is largely changed by zooming. I was able to do it. (3) In the lens hood in which the integrally formed protrusion member is engageable with the engagement groove of the front frame of the lens barrel, two to a plurality of stepped portions in the circumferential direction are provided on both sides in the optical axis direction of the protrusion member. By providing the projection member with one or more cutouts, the deformation of the hood cylinder to the inner peripheral side is minimized when the tightening knob is rotated and tightened to be attached to the lens barrel. The lens hood can be easily removed from the lens barrel at low temperatures. (4) Since the rotation amount about the optical axis of the hood and the extension amount of the hood with respect to the first lens closest to the subject have a predetermined relationship, the hood extension device is provided to center the optical axis of the hood. By setting a predetermined relationship between the rotating operation and the amount of feeding the hood with respect to the lens barrel, the hood can be extended to any desired length only by rotating the hood.

[0014]

【Example】

Example 1. 1 to 3 show a first embodiment of the present invention, and FIG. 1 is a vertical cross-sectional view of a lens barrel and a hood, which are most characteristic of the present invention. In the figure, reference numeral 1 denotes a lens barrel front frame of a zoom lens, which has a known bayonet claw 1a, a tapered portion 1b, and a locking groove 1c of a hood.

A hood bayonet member 2 has a bayonet portion 2a, a through hole 2b, a locking portion 2c of a hood body (described later), a fitting portion 2d, and an abutting portion 2e. In the through hole 2b, a roller 3 that is locked in the locking groove 1c of the lens barrel front frame 1,
A click ball 5 that engages with the spring 4 and the hood body is fitted therein.

Reference numeral 6 denotes a hood body, which is provided with notches 6b and 6c continuously from the tip 6a. The hood main body is in the upper, lower (short side) direction, left and right (long side) of the zoom lens when the widest angle is used. ) Direction, the incident light flux in the diagonal direction is set to a length that does not fall. Further, on the inner peripheral side, there is a protrusion 6d that engages with and engages with the engaging portion 2c and the fitting portion 2d of the hood bayonet member 2, and one end 6e and the abutting portion 2e of the bayonet member 2 are provided. The hood body 6 abuts and is rotatably held by the bayonet member 2. 6f is a click groove provided on the inner peripheral side of the hood body 6 at intervals of about 45 °,
The hood bayonet member 2 is locked at the position of the click ball 5. Reference numeral 6g is a guide groove of a light shielding plate 7 (described later) provided in the hood body 6 in parallel with the optical axis, and has a click portion 6g 'at a specific zoom lens position on the groove wall surface.

Reference numeral 7 denotes a light-shielding plate, which has an elastic projection 7a penetrating the guide groove 6g of the hood body 6, and the end of the elastic projection 7a is caulked or fixed with a screw or the like to prevent the removal. A light shielding plate 7 is slidably attached to the outer surface of the hood body 6.

Next, in the above structure, the preliminary hood body 6
The attachment of the hood bayonet member 2 assembled to the lens barrel front frame 1 and the hood action will be described. First, as shown in FIG. 2, by inserting the bayonet portion 2a of the hood bayonet member 2 into the bayonet portion of the lens barrel front frame 1 and rotating it,
The roller 3 is the tapered portion 1b of the bayonet claw 1 of the lens barrel front frame 1.
The hood body 6 which is slid on the hood bayonet member 2 and is locked in the locking groove 1c can be mounted on the lens barrel front frame 1.

Next, the action of the hood will be described. FIG. 3 shows a state in which the zoom lens is used at the widest angle. The light shield 7 is slid in the optical axis direction depending on the position where the zoom lens is used, and the elastic protrusion 7a causes the guide groove 6 of the hood body 6 to slide.
By being locked by the click part 6g 'of g, the position specified by this click part 6g' (position on the telephoto side from the widest angle)
It enables to cut the harmful light incident on the focal length.

When the hood main body 6 is rotated with respect to the hood bayonet member 2, the click groove 6f is locked at the position of the click ball 5 and the light shield plate 7 which is normally positioned right above is provided.
The position can be changed, not only the position directly above, but diagonally,
It is possible to block the incidence of harmful light from directly beside. Example 2. 4 to 6 show Embodiment 2 of the present invention, FIG. 4 is a vertical cross-sectional view of an interchangeable lens showing a state of zooming to a wide angle side, and FIG. 5 is a vertical cross-section of the interchangeable lens of FIG. 4 to a state of zooming to a telephoto side. FIG. 6 is an exploded perspective view of the tip of the hood and the interchangeable lens shown in FIGS. 4 and 5. 4 to 6, 11 is a fixed barrel, 12 is a zoom operation ring rotatably held by the fixed barrel 11, 13 is a zoom connecting key, 14 is a cam barrel rotatably held, and 14a is a cam. Gears provided on the outer periphery of the cylinder 14, 14b are cam grooves, 1
5 stationary guide tube held by the fixed barrel 11, 15a parallel keyway and the optical axis provided in the guide cylinder 15, L ₁ ~L ₄
Is a lens group that constitutes the zoom lens, and includes L ₁ and L ₃
Is a variator lens, L ₂ is a compensator lens that also serves as a focusing lens, and L ₄ is a fixed lens.

Reference numeral 16 denotes a rectilinear barrel that moves in the optical axis direction by zooming, 16a denotes a cam follower fixed to the rectilinear barrel 16, 17 denotes a hood holding cylinder fixed to the rectilinear barrel 16, and 17
a is a cam follower for a hood which is provided in three protrusions on the outer periphery of the hood holding cylinder, 17b is a hole formed in the hood holding cylinder 17,
Reference numeral 18 is a lens frame holding the lens group L ₃ , 19 is a lens frame holding the lens group L ₂ , and 20 is a lens frame holding the lens group L ₁ .

Reference numeral 21 is a hood movably held outside the hood holding frame 17, 21a is a hood feeding cam groove provided inside the hood 21, and 21b is provided inside the hood 21 along the cam groove 21a. The gear 21c is a mounting groove for mounting an accessory such as another hood provided at the tip of the hood 21.

Reference numeral 22 denotes a first rotation transmitting shaft that rotates in parallel with the optical axis, 22a denotes a small gear formed at an end of the first rotation transmitting shaft 22, and 22b denotes a center of the first rotation transmitting shaft 22. It is a D cut hole formed.

Reference numeral 23 denotes the first rotation transmission shaft 22 parallel to the optical axis.
A second rotation transmission shaft that rotates with the second rotation transmission shaft 23a is a small gear formed at the end of the second rotation transmission shaft 23, and 23b is a second rotation transmission shaft.
The rotation transmitting shaft 23 is a D-cut portion fitted in the D-cut hole 22b so as to be slidable only in the optical axis direction.

In the above structure, the zoom operation ring 12 is connected by the zoom connection key 13 so as to rotate integrally with the cam barrel 14. When the zoom operation ring 12 is rotated, the cam barrel 14 rotates about the optical axis. Since the cam follower 16a of the rectilinear barrel 16 is fitted in the cam groove 14b and the key groove 15a of the guide barrel 15, the rectilinear barrel 16 is extended in the optical axis direction by the rotation of the cam barrel 14.

The straight-moving barrel 16 includes a lens frame 20 for holding the first lens group, a hood holding barrel 17, and a second rotation transmitting shaft 23.
In order to move the lens, the zoom operation ring 12 is rotated and zoomed to the telephoto side. As a result, as shown in FIG. 5, the entire lens length becomes long.

At this time, the gear 14a of the rotating cam barrel 14
The first rotation transmission shaft 22 is rotated by the gear 22a engaged with the first rotation transmission shaft 22. Since the first and second rotation transmission shafts 22 and 23 are connected to the D-cut hole by a shaft, the second rotation transmission shaft 23
Also rotates by zooming.

Since the cam groove 21a of the hood 21 is engaged with the cam floor 17a of the hood holding cylinder 17, when the hood 21 is rotated, the hood 21 is extended along the cam groove 21a. Since the gear 23a formed on the second rotation transmission shaft 23 that rotates by zooming meshes with the gear 21b inside the hood 21, the hood 21 rotates and is extended in the optical axis direction by zooming.

At this time, the shape of the cam groove 21a is given a predetermined shape so that the optimum extension is performed with respect to the change in the angle of view due to zooming. Example 3. 7 to 9, reference numeral 31 denotes a front frame located at the front end of the lens barrel, and the outer shape of the front end of the front frame 31 is D1. Reference numeral 32 is an engagement groove having a taper on both sides, and the groove bottom diameter is D2. Reference numeral 33 denotes a hood engaging portion where the taper of the engaging groove 32 is extended, and its outer shape is D3. Reference numeral 34 is a hood cylinder member formed of resin, and has a projection member 35 integrally formed. The projection member 35 has notches 3 at one or more locations.
5'is provided and the engaging groove 3 of the front frame 31 is provided.
It has a taper substantially equal to the taper of No. 2 and is engageable, and its inner diameter is D4. The inner diameter D4 is eccentric from the center of the hood cylinder portion 34 by δ, and the taper of the protruding member 35 does not change and the height gradually decreases.
The relationship between the inner diameter D4 and the outer diameter D1 of the front frame 31 is D4> D
It is set to 1.

Reference numeral 41 denotes a step portion integrally formed with the hood cylinder member 34 at two circumferential positions on both sides of the protrusion member 35 in the optical axis direction, and the inner diameter thereof is D5. The relationship between the inner diameter D5 and the outer diameter D3 of the hood locking portion of the lens barrel 31 is D5.
> D3 is set.

The fastening member A to the lens barrel is arranged on the same line as the center line xx 'of the projection member 35,
The tightening member A is composed of the following components.
36 is a pedestal of a fastening part, and has a screw 36a.

Numeral 37 is a tightening knob which has a threaded portion 3 on its inner circumference.
7a, and the screw portion 37a is screwed with the screw 36a of the tightening pedestal 36. 38 is a tightening knob shaft, which is integrated with the tightening knob 37 by a knock pin or the like,
A bearing portion 38a of the tightening washer 39 is provided at one end, and penetrates through the tightening portion pedestal 36.

Reference numeral 40 denotes a tightening piece, which has a taper 40a and a through hole 40b which are substantially the same as the taper of the engaging groove 32 of the lens barrel 31, and the tightening knob shaft 3 is provided in the through hole.
It is retained and held by 8 and the tightening washer 39.

In the above structure, FIG. 8 is a view showing a state in which the hood cylinder member 34 is about to be attached to the front frame 31 of the lens barrel. By rotating the tightening knob 37 counterclockwise, the tightening piece 40 is released to a diameter larger than the tip outer diameter D1 of the front frame 31 of the lens barrel, and the hood cylinder member 34 is inserted. The tightening piece 40 and the projection member 35 abut on the locking portion 33, and the position of the hood cylinder member 34 in the optical axis direction is determined.

When the tightening knob 37 is rotated to the right at that position, the knob shaft 38 slides in the direction of the optical axis along the taper of the tightening piece 40 and the taper of the engaging groove 32 of the front frame 31 of the lens barrel. And engages with the engaging groove 32.

When the tightening knob 37 is further rotated to the right in this state, the protruding member 35 in the opposite direction is moved to the above-mentioned tightening piece 40.
Similarly to the above, the hood cylinder member 34 is engaged with the taper of the engagement groove 32 of the front frame 31 of the lens barrel, and is retained by the front frame 31 of the lens barrel as shown in FIG.

However, since the hood cylinder member 34 is made of resin, when the tightening knob 37 is further tightened to the right, the hood cylinder member 3 is rotated.
4 deforms and the step 41 on the inner circumference and the outer shape D3 of the hood engaging portion abut against each other, and rotation of the tightening knob 37 and deformation of the hood tubular member 34 are restricted. The same applies when the hood cylinder member 34 is placed over the front frame 1 of the lens barrel. Since the projection member 35 of the hood cylinder member 34 and the engagement groove 32 of the lens barrel front frame 31 in this mounted state are partially engaged, the projections 35 are formed when the temperature changes, especially at low temperature. Even if the member 35 contracts, the hood cylinder member 34 can be easily attached and detached. Example 4. FIG. 10 shows another embodiment of the present invention. In the figure, 42 is a hood cylinder member formed of resin, 43 is a protrusion member, and the shape is the same as that shown in FIG. It is formed integrally with. Reference numeral 44 corresponds to the fastening portion pedestal of the embodiment of FIG. 7, and is formed integrally with the hood cylinder member 42.

The structure and operation other than the illustrated constituent elements 42 to 44 are exactly the same as those of the embodiment shown in FIG. Example 5. 11 to 14 show Embodiment 5 of the present invention, in which the focal length is from 35 mm on the wide angle side to 20 on the telephoto side.
FIG. 11 is a view showing a state in which the hood of the present invention is housed in the wide-angle side state of the zoom lens which changes to 0 mm, and FIG.
1 is a view showing a state in which the zoom lens shown in FIG. 2 is on the telephoto side and the hood is extended according to the telephoto angle of view, FIG.
3 is a view showing a state in which the hood is removed from the zoom lens shown in FIG. 11, and FIG. 14 is a perspective view showing a hood removed from the zoom lens shown in FIG. 11 and a main part of the tip of the lens.

In FIGS. 11 to 12, 51 is a hood, 51a is a focal length scale for feeding the hood, 52 is a lens barrel which expands and contracts by zooming, 52a is an index line which is a guide for the rotational position of the hood, and 53 is A zooming operation ring for zooming, 53a is a focal length scale,
54 is a focusing ring for focusing,
Reference numeral 55 is a distance scale, and 56 is a mount for mounting the zoom lens on a camera body (not shown).

13 to 14, 51b is a cam groove formed inside the hood 51, and 51c, 51d and 5 are shown.
1e, 51f and 51g are click grooves formed inside the hood 51, and 52d is a hood fitting portion formed slightly higher than the outer surface of the lens barrel 52 on the extension of the index line 52a. 52d cam follower
b, click claws 52c are provided.

In the above structure, the focal length is changed from 35 mm to 200 by rotating the zooming operation ring 53.
However, at that time, the lens barrel 52 is short on the short focus side as shown in FIG. 11 and extends long on the long focus side as shown in FIG. 12, and the angle of view is wide on the short focus side. It changes narrowly on the side.

The hood 51 is attached to the outside of the lens barrel 52 and slidably fitted in the fitting portion 52d. Since the cam follower 52b is engaged with the cam groove 51b inside the hood, the hood 51 is fed out along a predetermined cam locus by the turning operation of the hood 51. On the outer side of the hood 51, the same focal length scale 51a as the focal length scale 53a displayed on the zooming operation ring 53 is displayed, and the scale of the same number as the focal length used for photographing is used as the index line 5.
According to 2a, the optimal feeding amount of the hood 51 is set.

At this time, the click claw 52 of the lens barrel 52
c and the click grooves 51c to 51g provided on the inside of the hood 51 are engaged with each other at each rotation angle corresponding to the position of the focal length scale 51a of the hood 51, so that each position of the focal length scale 51a has an appropriate position. Holding power is generated. The click groove 51c is a click groove for holding the hood 51 in the most retracted stored state, and the click groove 51d to the click groove 51g.
Is a click groove at a turning position corresponding to a focal length scale of 35.80.135.200 mm.

[0044]

As described above, according to the first aspect of the present invention, since the light shielding plate is slidably attached to the hood body, it is possible to cut off harmful light incident from the entire area of the zoom lens or outside the necessary area. There is an effect. Further, by rotating the hood main body, there is an effect that it is possible to cut off harmful light incident not only right above but also obliquely, laterally, etc.

According to the inventions of claims 2 and 3,
Since the rotational force from the member that rotates due to zooming operation is transmitted to the hood through the rotation transmission shaft that is arranged parallel to the optical axis, it is possible to adjust the hood of a zoom lens whose overall lens length changes significantly by zooming. The zooming force can be transmitted to the hood, and the hood feeding device can be manufactured with almost no increase in cost with respect to the built-in hood of the system that does not interlock with the conventional zooming.

Further, by having a hood having an optimum length for each focal length due to zooming, the deterioration of the contrast due to the internal reflection in the lens barrel and the ghost due to the reflection of the lens surface are remarkably reduced, and the quality is improved. There is an effect that you can get high quality pictures.

According to the inventions of claims 4 and 5,
By providing a step on the inner circumference of the lens hood cylinder and providing a notch in a part of the protrusion member, when tightening the lens barrel,
It is possible to limit the amount of deformation of the hood cylinder, and at the same time, it has an effect that the load / unload property is good even when the temperature changes, especially at low temperatures.

According to the sixth to eighth aspects of the invention, however, since the cam groove is formed inside the hood and the cam groove is engaged with the cam follower of the lens barrel, the hood having a fixed length is compared with the conventional hood. It is possible to make the hood of the optimum length against the change of the angle of view due to zooming without increasing the manufacturing cost. Recently, zoom lenses have become to have a higher zoom ratio, and it has not been so important to change the length of the hood at a zoom ratio of about 2 times in the past, but as the zoom ratio increases, the wide-angle side becomes wider. In the conventional hood where the length of the hood was determined by the angle of view, there was no hood effect on the telephoto side. However, since the present invention has the above-described configuration, if the hood is set to the wide-angle position, it can be used without operating the hood in accordance with zooming as in the conventional case. If you use the hood by extending it to the optimum length, you can get high contrast pictures with less flare. When the hood is not used, it is possible to remove it.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a lens barrel and a hood showing a first embodiment.

FIG. 2 is a cross-sectional view taken along the line AA of FIG.

FIG. 3 is a plan view seen from the direction of arrow B in FIG.

FIG. 4 is a vertical cross-sectional view showing a state where the interchangeable lens of Example 2 is zoomed to the wide-angle side.

FIG. 5 is a vertical cross-sectional view showing a state where the interchangeable lens of FIG. 4 is zoomed to the telephoto side.

FIG. 6 is an exploded perspective view of the hood and the tip of the interchangeable lens.

FIG. 7 is a vertical sectional view of an accessory and a lens barrel showing a third embodiment.

8 is a cross-sectional view of FIG. 7 showing a state before mounting the lens hood.

FIG. 9 is a view showing a state in which a lens hood is attached.
FIG.

FIG. 10 is a vertical sectional view of an accessory and a lens barrel showing a fourth embodiment.

FIG. 11 is a front view showing a lens barrel of Embodiment 5 showing a state in which a hood is stored with the zoom lens on the wide-angle side.

FIG. 12 is a front view of a lens barrel showing a state in which a hood is extended to an optimum length for telephoto with a zoom lens on the telephoto side.

FIG. 13 is a front view of the lens barrel showing a state in which a hood is removed from the zoom lens.

FIG. 14 is a perspective view of the removed hood and the zoom lens tip portion.

[Explanation of symbols]

 1 Lens barrel front frame 2 Hood bayonet member 6 Hood main body 7 Light-shielding plate 12 Zoom operation ring 13 Zoom connecting key (connecting means) 14 Cam barrel (direct connecting means) 17a Cam follower for hood (hood feeding device) 21a Cam groove (hood feeding device) ) 21b Spur gear 22 Hood rotation transmission shaft 23a Small gear 31 Lens barrel front frame 32 Engagement groove 35 Projection member 35 'Notch 36 Tightening part pedestal 51b Cam groove (hood feeding device) 51c to 51g Click groove (click device) 52b Cam follower (hood feeding device) 52 Zoom operation ring 53 Focal length scale

Claims (8)

[Claims] 1. A hood bayonet member joined to a front frame of a lens barrel by a bayonet, a hood main body attached to the hood bayonet member so as to be rotatable and lockable at an appropriate position, and the hood main body in the optical axis direction. Slideable and
A lens hood, comprising: a light-shielding plate attached so that it can be locked at an appropriate position. 2. A hood feeding device in which a first lens closest to a subject that moves by zooming, a rotation amount of an internal hood about an optical axis, and a feeding amount of the hood with respect to the first lens have a predetermined relationship. And a hood rotation transmission shaft disposed in parallel with an optical axis that transmits a rotational force to a small gear that meshes with a spur gear provided on the inner circumference of the hood,
A lens provided with a connecting means for rotating the hood rotation transmission shaft in association with a zoom operation ring rotated by a zooming means so as to obtain an optimum hood extension amount according to an angle of view changed by zooming. hood. 3. The lens hood according to claim 2, wherein a hood mounting portion for mounting another hood is provided at the tip of the built-in hood. 4. A lens hood in which an integrally molded protrusion member is engageable with an engagement groove of a front frame of a lens barrel, wherein two or more stepped portions in the circumferential direction are provided on both sides in the optical axis direction of the protrusion member. And a plurality of notches formed in the protrusion member. 5. The lens hood according to claim 4, wherein the tightening part pedestal is integrally formed. 6. A lens hood provided with a hood feeding device having a predetermined relationship between a rotation amount of the hood about an optical axis and a feeding amount of the hood with respect to a first lens closest to a subject. . 7. The lens hood according to claim 6, wherein the hood feeding device is a cam groove provided on the inner circumference of the hood and a cam follower provided on the outer circumference of the front end of the lens barrel. 8. The lens hood according to claim 6, further comprising a click device for generating a click at a rotational position of the hood that corresponds to an optimum hood extension amount with respect to the focal length scale displayed on the zoom operation ring.