JP2003084336A - Lens hood - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens hood, which can be attached to photographing equipment with a specified angle phase, with a small number of parts. SOLUTION: The attaching mechanism of the lens hood 1 can be constituted without increasing the number of parts by providing a female screw 2a in the hood 2 of the lens hood 1 and a male screw 4b in the photographing equipment 4 and fastening the respective screws.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art In recent years, in photographing equipment such as a silver halide camera and a video camera, in order to obtain a good image without flare, a light-shielding rib having horizontal portions vertically provided on the inner surface of a lens hood may be formed. The lens hood provided with the light-shielding ribs needs to have a predetermined mounting angle phase due to optical constraints such as vignetting.

A conventional lens hood will be described below.

FIG. 3 is a sectional view of a conventional lens hood and a photographing device (video camera) as seen from the front. FIG. 3 (a) is a sectional view taken along the line aa in FIG. 5, and FIG.
3 is a sectional view taken along line bb in FIG. FIG. 4 is a cross-sectional view (partially see-through view) showing a state in which a conventional lens hood is attached to an imaging device, and FIG. 5 is a perspective view for explaining the attaching operation of the conventional lens hood.

In the figure, a mask 13 having light-shielding ribs 13b provided with horizontal portions 13a at the top and bottom is integrated with the hood 12 by fitting, and the lens hood 11 is formed by these two parts. The lens hood 11 includes a rib 12 a provided on the hood 12 and a projection 14 of the photographing device 14.
The structure is such that when a is fastened, it does not fall off the photographing device 14. Further, when the lens hood 11 is attached to the photographing device 14 at a predetermined angular phase, the click ball 15 biased by the click spring 16 fits into the click groove 12b provided in the rib 12a. .

The operation of the conventional lens hood constructed as above will be described below.

The user attaches the lens hood 11 to the photographing device 14
As shown in FIG. 3 and FIG.
The notch of the protrusion 14a is aligned with the notch, the rib 12a is inserted into the notch, and the lens hood 11 is rotated in the direction of arrow A by a predetermined angle. Then, as shown in FIG. 4, the rib 1
2a and the protrusion 14a are engaged with each other, and the lens hood 11 is in a state of not falling off from the photographing device 14.

Further, the click ball 15 urged by the click spring 16 fits into the click groove 12b, and the lens hood 11 stops turning with moderation.
The lens hood 11 is mounted on the lens optical axis of the photographing device 14 at a predetermined angle phase.

[0009]

However, in the conventional structure, the click ball 15 and the click spring 16 for urging the lens hood 11 are required to fix the lens hood 11 at a predetermined angular phase, and the number of parts and the number of assembly steps are increased. Had the drawback of leading to an increase in

An object of the present invention is to solve the above-mentioned conventional problems, and an object thereof is to provide a lens hood which can be mounted on a photographing device at a predetermined angle phase with a small number of parts.

[0011]

To achieve this object, the lens hood of the present invention is a lens hood which can be mounted on the tip of the optical axis of a lens barrel, and is rotatably held and incident on the lens hood. The present lens hood is attached to the lens barrel, which includes a light blocking unit for blocking unnecessary light rays, a positioning unit provided on the light blocking unit, and a positioned unit provided on the lens barrel and engaged with the positioning unit. In doing so, the positioning means and the positioned means are engaged with each other.

With this configuration, it is possible to provide a lens hood that can be mounted on a photographing device at a predetermined angle phase with a small number of parts.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The invention described in claims 1 and 2 of the present invention is a lens hood which can be mounted on the tip of the optical axis of a lens barrel, and which does not need to be rotatably held and incident on the lens hood. When the present lens hood is mounted on the lens barrel, the light shielding unit for blocking the light beam, the positioning unit provided on the light shielding unit, and the positioned unit provided on the lens barrel and engaged with the positioning unit are provided. The positioning means and the positioned means are engaged with each other. With such a configuration, it is possible to provide a lens hood that can be mounted on an imaging device at a predetermined angular phase with a small number of parts. Becomes

Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIG. 1 is a cross-sectional view showing a state in which a lens hood according to an embodiment of the present invention is attached to a photographing device, and FIG. 2 is for explaining an attaching operation of the lens hood according to the present embodiment. FIG.

In the drawing, reference numeral 4 denotes a photographing device capable of photographing an image of a subject, and this drawing shows a lens barrel which is a part thereof. The photographing device 4 corresponds to, for example, a video camera, but may be a device that uses a lens hood, such as a silver salt camera or a digital camera. Note that, in FIG. 1, for convenience of description, only the vicinity of the lens hood 1 mounting portion of the imaging device 4 is shown in a sectional view.

Reference numeral 1 denotes a lens hood which is attached to the tip of the photographing device 4 to block unnecessary light rays, and in this embodiment, is screwed to a male screw 4b which is a second screw portion formed at the tip of the photographing device 4. Then it is installed.

Reference numeral 2 denotes a hood arranged at the outermost portion of the lens hood 1, and the user can attach and detach the hood 2 by holding the outer periphery of the hood 2 and rotating it. 2a
Is a female screw which is a first screw portion which is provided inside the hood 2 and is screwed with the male screw 4b of the photographing device 4.

Reference numeral 3 denotes a mask, which is rotatably held in the hood 2 and has an opening at a substantially central portion, which is an incident light limiting means for limiting unnecessary incident light. The light-shielding rib 3a having a substantially quadrangular opening forms a part of the opening provided in the light-shielding rib 3b, and is a horizontal portion formed parallel to the upper and lower sides of the opening, and is incident on the horizontal portion 3a. The vertical direction of the light beam is restricted. Reference numeral 3c denotes a phase matching convex portion which is a positioning means provided on the outer circumferential circle of the mask 3 and which is provided in a shape projecting in the optical axis direction (on the side of the photographing device 4). By engaging with a certain phase matching recess 4a,
A predetermined angular phase can be determined on the optical axis of the lens of the photographing device 4, and it can be mounted only at this angular phase. In addition, in the present embodiment, only one phase matching convex portion 3c and one phase matching concave portion 4a are provided.
You may provide in multiple places. In addition, the alignment protrusion 3c
Is provided integrally with the mask 3, and a separate part is not provided at the time of formation, but a part of the mask 3 is formed into a shape as illustrated or partially bent. Therefore, even if the alignment protrusion 3
Increasing the number of c does not lead to an increase in the number of parts. Further, in the present embodiment, the mask 3, the horizontal portion 3a, the light-shielding rib 3b, and the alignment convex portion 3c are integrally molded in order to reduce the number of parts. They may be configured by separate parts within a range that does not increase.

The hood 2 holds the mask 3 rotatably, and the hood 2 is rotated to rotate the female screw 2a and the photographing device 4.
By fastening the male screw 4b provided on the camera, the lens can be mounted and fixed on the optical axis of the lens of the photographing device 4. The lens hood 1 is formed by the two parts of the hood 2 and the mask 3.

The operation of the lens hood of the present embodiment configured as described above will be described below with reference to FIGS. 1 and 2.

When the user mounts the lens hood 1 on the photographing device 4, the lens hood 1 is moved from the state shown in FIG. Then, the phase matching convex portion 3c of the mask 3 is inserted into the phase matching concave portion 4a of the photographing device 4 as shown by an arrow D. Next, the female screw 2a of the hood 2 is engaged with the tip of the male screw 4a of the photographing device 4, and the hood 2 is rotated in the screw fastening direction (arrow C direction).
Then, the female screw 2a and the male screw 4a are fastened, and when the hood 2 is rotated to a predetermined position, the lens hood 1 is attached and fixed to the photographing device 4 as shown in FIG.

Since the mask 3 is rotatably held with respect to the hood 2 when the hood 2 is rotated, even if the hood 2 is rotated and continuously fastened to the photographing device 4, the mask 3 will not be removed. Phase matching convex portion 3c and phase matching concave portion 4
Since it is engaged with a, it does not rotate, and it spins inside the hood 2 without changing the position in the rotation direction. The mounting angle phase of the mask 3 with respect to the imaging device 4 is positioned at a predetermined angle because the phase matching convex portion 3c is engaged with the phase matching concave portion 4a, and this position can satisfy the optical constraint condition. Is set to.

When the lens hood 1 is detached from the photographing device 4, the lens hood 1 is rotated in the direction opposite to the arrow C (counterclockwise when viewed from the lens hood side), whereby the female screw 2a and the male screw 4b are rotated. The lens hood 1 can be disengaged from the imaging device 4 by being unscrewed. Even during this detaching operation, the mask 3 remains idly inside the hood 2 without changing its position.

Although the lens hood 1 and the photographing device 4 are fastened to each other by screwing in this embodiment, the ribs and the protrusions may be engaged with each other as shown in the above-mentioned prior art.

As described above, according to this embodiment, the hood 2 of the lens hood 1 is provided with the female screw 2a, and the photographing device 4 is provided.
Since the male screw 4b is provided on each of them and the respective screws are fastened to each other, the mounting mechanism of the lens hood 1 can be configured without increasing the number of parts.

Further, the mask 3 provided on the lens hood 1 is rotatably held on the hood 2, and the concave portion and the convex portion for positioning the mask 3 are provided, so that the lens hood 1 is rotated and the photographing device 4 is rotated. Mask 3 even when attached to
The position (angle) of does not change, and it can be reliably mounted optically.

Further, the lens hood 1 is provided with the female screw 2a, the photographing device 4 is provided with the male screw 4a, and the lens hood 1 is attached to the photographing device 4 by screwing the respective screws together. The attachment / detachment operation can be performed.

[0029]

As described above, the present invention has an excellent effect that it is possible to provide a lens hood with a small number of parts, which can be mounted on a photographing device by positioning at a predetermined angle phase. Is.

[Brief description of drawings]

FIG. 1 is a sectional view of a lens hood according to an embodiment of the present invention.

FIG. 2 is a perspective view for explaining a mounting operation of the lens hood according to the embodiment of the present invention.

FIG. 3 is a front sectional view showing a configuration of a conventional lens hood and a fastening portion of a photographing device (video camera).

FIG. 4 is a cross-sectional view (partially transparent view) of a conventional lens hood.

FIG. 5 is a perspective view for explaining a mounting operation of a conventional lens hood.

[Explanation of symbols]

1 lens hood 2 hood 2a female screw 3 masks 3a Horizontal part 3b Shading rib 3c Phase matching convex part 4 Photography equipment 4a Phase matching recess 4b male screw

Claims (2)

[Claims] 1. A lens hood that is detachably attached to the tip of the optical axis of a lens barrel, and is provided in the incident light limiting means for rotatably held by the lens hood to limit the incident light. Positioning means and positioning means provided on the lens barrel and engaged with the positioning means, and engaging the positioning means and the positioned means when the present lens hood is mounted on the lens barrel. Lens hood that is characterized by. 2. A first screw portion provided on the present lens hood and a second screw portion provided on a lens barrel, and when the lens hood is attached to the lens barrel, the first screw portion is provided. The lens hood according to claim 1, wherein the threaded portion of the lens hood is fastened to the second threaded portion.