JP2013210447A - Lens hood - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens hood capable of having a lens cap attached regardless of the presence of a lens accessory and not spoiling operability of a filter.SOLUTION: A lens hood capable of being attached to a lens barrel and including a light shielding section for shielding incidence of light into the lens barrel includes a first connection section composed of one of a male screw and a female screw formed on the light emission side and a second connection section composed of the other of the male screw and the female screw formed on the light incidence side. In this case, a pitch and a nominal diameter of the one of the male screw and the female screw are formed to be capable of connecting to the lens barrel. The pitch and the nominal diameter of the other of the male screw and the female screw are formed to be identical to the pitch and the nominal diameter of the one of the male screw and the female screw.

Description

  The present invention relates to a lens hood that can be attached to a lens barrel.

  2. Description of the Related Art Conventionally, some lens barrels used in optical devices such as a still camera, a digital camera, and a video camera are provided with a mounting screw for mounting an accessory at the tip. A lens accessory such as a polarizing filter or a hood for cutting harmful light is attached to the mounting screw.

  Here, when an optical device is not used, it is common to attach a lens cap for protecting the lens front surface to the lens barrel. To attach the lens cap, remove the lens accessory from the lens barrel. I had to. That is, every time the optical device is used, it takes time to reattach the lens accessory to the lens barrel. In order to save such trouble, for example, Patent Document 1 discloses a lens hood in which a lens cap can be attached to a lens hood attached to a lens barrel.

JP 2006-58786 A

  However, in the lens hood disclosed in Patent Document 1, the lens cap can be attached only to the lens hood. Therefore, in the configuration of Patent Document 1, it is impossible to attach the lens cap unless the lens hood is attached to the lens barrel. Further, in the configuration of Patent Document 1, since the rotation operation unit of the filter is installed inside the hood, when the filter is used, the hood becomes an obstacle and the filter cannot be rotated.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a lens hood that can be fitted with a lens cap regardless of the presence of a lens accessory and that does not impair the operability of the filter. .

  In order to solve the above-described problems, the present invention is a lens hood that can be attached to a lens barrel and has a light shielding portion that blocks light from entering the lens barrel, and is formed on the light emission side. A first connecting portion made of one of the male screw and the female screw, and a second connecting portion made of the other of the male screw and the female screw formed on the light incident side, and one of the male screw and the female screw. The pitch and the nominal diameter are formed so as to be connectable to the lens barrel, and the other pitch and the nominal diameter of the male screw and the female screw are the same as the pitch and the nominal diameter of the male screw and the female screw. It is formed as follows.

  According to the present invention, it is possible to provide a lens hood that can be fitted with a lens cap regardless of the presence of a lens accessory and that does not impair the operability of the filter.

It is the figure which attached the lens hood which concerns on embodiment of this invention to the lens-barrel. It is the figure which attached the lens accessory directly to the accessory attachment ring. It is a figure which shows the light-shielding effect of the lens hood which concerns on embodiment of this invention. It is the figure which changed a part of embodiment shown in FIG.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  First, the structure of the lens hood 1 which concerns on one Embodiment of this invention is demonstrated. FIG. 1 is a cross-sectional view of an essential part showing a state in which a lens hood 1 according to this embodiment is mounted on a lens barrel 2. The lens hood 1 is a lens accessory that can be attached to a lens barrel that is connected to or fixed to an imaging device (optical apparatus) such as a digital still camera or a video camera, and blocks the incidence of strong light rays. As shown in FIG. 1, the lens barrel 2 has an accessory mounting ring 2a at the tip thereof, and the lens hood 1 is attached to the accessory mounting ring 2a by screwing so that a user's desired use condition can be obtained. Can be attached and detached. The lens hood 1 of the present embodiment is a so-called barnacle-type lens hood whose opening diameter is smaller than the opening diameter of the lens barrel 2 on the attachment side.

  The lens hood 1 has an annular shape centered on an opening that allows the incident light from the subject side to be emitted toward the lens barrel 2 side, and includes a first connection portion 1a and a second connection portion 1b. A main body 1c (a broken line region in FIG. 1) and a light shielding part 1d extending inward (optical axis side) from the main body 1c are included. In particular, it is desirable that the outermost peripheral diameter of the lens hood 1 be matched with the outer peripheral diameter of the accessory mounting ring 2a (the front end portion of the lens barrel 2), that is, substantially match. Normally, the material of the accessory mounting ring 2a is often a resin from the viewpoint of weight reduction. On the other hand, the lens hood 1 is desirably manufactured from, for example, an aluminum alloy in order to reduce biting with the accessory mounting ring 2a made of a resin material from the viewpoint of weight reduction. From the same viewpoint, the volume of the lens hood 1 is set smaller than the accessory mounting ring 2a.

  First, the 1st connection part 1a is comprised with the external thread 10a. The male screw 10a is installed on the light emitting side of the main body 1c of the lens hood 1, and is screwed with a female screw 2b installed at the tip of the accessory mounting ring 2a. That is, the pitch and the nominal diameter of the male screw 10a of the lens hood 1 are the same as the pitch and the nominal diameter of the female screw 2b of the accessory mounting ring 2a. With this male screw 10a, the lens hood 1 is integrated with the lens barrel 2 as shown in FIG.

  Moreover, the 2nd connection part 1b is comprised by the internal thread 10b. The female screw 10b is installed on the light incident side of the main body 1c, and has the same pitch and nominal diameter as the male screw 10a. Therefore, it can be screwed with a male screw of a screw-in type lens accessory such as the lens cap 3 and the polarizing filter 4. In the example shown in FIG. 1, the lens cap 3 is attached to the female screw 10 b of the lens hood 1.

  Here, a lens accessory for the lens barrel 2 may be attached to the lens barrel 2. For example, there are a polarizing filter 4 and a lens cap 3 as such a lens accessory. That is, the thread portion of the lens accessory is the same as the pitch and the nominal diameter of the female screw 2b of the accessory mounting ring 2a. Therefore, the lens hood 1 and the polarizing filter 4 can be connected to the accessory mounting ring 2a of the lens barrel 2, and the same lens cap 3 can be connected to any of the lens hood 1, the polarizing filter 4, and the accessory mounting ring 2a. Can also be worn. For example, as shown in FIG. 1, the lens cap 3 can be attached to the lens hood 1. Further, as shown in FIG. 2A, the lens cap 3 may be directly attached to the accessory mounting ring 2a. In addition, as shown in FIG. 2B, the lens cap 3 may be attached to a polarizing filter 4 that is a lens accessory. Thus, the lens cap 3 can be attached regardless of the presence or absence of the lens accessory.

  The light shielding portion 1d of the lens hood 1 is configured to block unnecessary light, and is formed between the male screw 10a and the female screw 10b in the thickness direction of the lens hood 1 so as to extend inward from the main body portion 1c of the lens hood 1. Therefore, when the polarizing filter 4 is attached, the rotation operation unit 4a of the polarizing filter 4 is exposed on the outer peripheral surface. Therefore, the operability is improved as compared with the so-called flower-shaped lens hood 1 in which the rotation operation portion 4 a of the polarizing filter 4 is provided inside the lens hood 1.

  Further, the lens hood 1 has a low reflectance so that the black alumite treatment is performed so that the hit light is diffusely reflected. The black alumite treatment is a treatment for forming an oxide film on the product surface by anodic oxidation or the like. Since the electrode is applied in the anodizing process, an alumite contact portion 1e which is a trace of the electrode remains in the lens hood 1. The alumite contact portion 1e is provided on the male screw side (image surface side) of the light shielding portion 1d and in the circumferential groove portion on the inner periphery. Accordingly, when the lens hood 1 is attached to the lens barrel 2, the appearance is not impaired.

  Next, the light shielding effect of the lens hood 1 will be described with reference to FIG. FIG. 3 is a cross-sectional view of the main part including the optical axis X of the lens barrel 2, and shows the light shielding efficiency with respect to the light incident on the lens 2 c on the front surface of the lens barrel 2 using the vignetting line 5. FIG. 3A shows a state in which the lens hood 1 and the polarizing filter 4 are attached to the lens barrel 2 in this order. FIG. 3B shows a state in which the polarizing filter 4 and the lens hood 1 are attached to the lens barrel 2 in this order. FIG. 3C shows a state where two polarizing filters 4 are stacked on the lens barrel 2 and the lens hood 1 is attached. Vignetting is a phenomenon in which a difference in brightness (decrease in the amount of peripheral light) occurs at the center and the periphery of an image, and vignetting occurs when a lens accessory or the like overlaps the vignetting line. The boundary where the vignetting occurs is called a vignetting line. In FIG. 3A and FIG. 3B, the lens hood 1 does not overlap the vignetting line 5. However, in the setting of FIG. 3B, the distance from the tip 1f of the light shielding portion of the lens hood 1 to the vignetting line 5 is shorter than that in FIG. Therefore, unnecessary light can be efficiently shielded. In FIG.3 (c), the light-shielding part 1d of the lens hood 1 has overlapped with the vignetting line 5, and if it uses by this setting, vignetting will generate | occur | produce. As described above, in FIG. 3B, the rotation operation portion 4a of the polarizing filter 4 is exposed on the outer peripheral surface, and the outermost peripheral diameter of the lens hood 1 is the accessory mounting ring 2a (the lens barrel 2). It is set according to the outer peripheral diameter of the tip. This improves the operability when the rotation operation portion 4a of the polarizing filter 4 between the lens hood 1 and the accessory mounting ring 2a is rotated.

  As described above, according to the present embodiment, it is possible to provide the lens hood 1 in which the lens cap 3 can be attached regardless of the presence of the lens accessory and the operability of the filter or the like is not impaired.

  In the embodiment of the present invention, the lens hood 1 that extends so that the shape of the light shielding portion 1d forms an opening in a substantially perpendicular direction of the optical axis X has been described. However, as shown in FIG. 4, it is also possible to extend the lens hood 1 so as to form an opening while having an inclination with respect to the optical axis X, thereby forming a substantially conical light shielding portion 1d ′.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to the said embodiment, A various deformation | transformation and change are possible within the range of the summary. For example, when a male screw is formed on the accessory mounting ring, the first connecting portion in the present invention is a female screw, and at the same time, the second connecting portion is a male screw. That is, the 1st connection part in this invention consists of one of an internal thread and a male screw, and a 2nd connection part consists of the other of an internal thread and an external thread.

DESCRIPTION OF SYMBOLS 1 Lens hood 1a 1st connection part 1b 2nd connection part 10a Male screw 10b Female screw 1d Light-shielding part 2 Lens barrel

Claims (4)

A lens hood that can be attached to a lens barrel and has a light shielding portion that blocks light from entering the lens barrel,
A first connecting portion formed of one of a male screw and a female screw formed on the light emitting side, and a second connecting portion formed of the other of the male screw and the female screw formed on the light incident side;
The pitch and nominal diameter of one of the male screw and the female screw are formed so as to be connectable to the lens barrel,
The other pitch and the nominal diameter of the male screw and the female screw are formed to be the same as the pitch and the nominal diameter of the male screw and the female screw.
This is a lens hood. It can be attached to the tip of the lens barrel,
The lens hood according to claim 1, wherein an outermost peripheral diameter is configured to match an outer peripheral diameter of the tip portion of the lens barrel.   The lens hood according to claim 1 or 2, wherein a process of diffusing and reflecting light incident on the lens barrel is performed. Made of aluminum alloy,
The treatment is an alumite treatment;
The lens hood according to claim 3, wherein an alumite contact portion is provided in a circumferential groove formed on an inner periphery closer to the first connection portion than the light shielding portion.

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