JPH09236849A - Filter holder and optical instrument auxiliary device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a filter holder capable of rapidly exchanging a filter, hardly causing scratch at the time of attaching/detaching the filter, and capable of being stably housed and held without being easily removed from a case in attaching the filter to a part of a lens barrel detachably in the case by specifying the structure of the case. SOLUTION: The front frame 1 and the rear frame 2 has first shelves 1a, 2a and second shelves 1b, 2b which become more dented respectively. The front frame 1 and the rear frame 2 constitute one element of the case and a sheet-like filter is inserted and detached through an inserted window installed between the first shelf 1a of the front frame 1 and the first shelf 2a of the rear frame 2 in a region 104 caught by the two frames. Furthermore, a part of the insertion window is provided with movable shielding means 7, 9 to cover a region of the insertion window and to limit the loading and the unloading of the filter in a part of this insertion window. Since level differences are provided between the first shelves 1a, 2a and the second shelves 1b 2b, the sheetlike filter can be inserted in a manner that the central section (effective face) of the filter is not rubbed by the wall faces of the front frame 1 and rear frame 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filter holder and an optical device auxiliary device using the same, and more particularly to a filter holder that is detachably provided on the optical axis of the lens barrel on the object side so as to change the shooting conditions. It is suitable for a video camera, a film camera and the like.

[0002]

2. Description of the Related Art Conventionally, in a photographic camera, a video camera or the like, a filter holder capable of accommodating and holding various filters is mounted on an optical axis of an object side of a lens barrel to shoot under various shooting conditions. I am trying.

At this time, an accessory (optical device auxiliary device) in which a hood, an adapter ring, or the like is attached to a filter holder attached to the lens barrel, particularly an accessory having a structure for storing and holding a sheet-like filter, has a sheet-like shape. The wall surface of the opening portion into which the filter is inserted is formed by a single surface, and the method or accessory in which the sheet filter is inserted into the opening portion and used is divided into two members, a front frame and a rear frame. A method of sandwiching a sheet-like filter in front and back with one member is used.

As a method of attaching the accessory to the lens barrel, a method of attaching a screw part or a bayonet portion provided on a part of the accessory to a part of the lens barrel by screwing or coupling it, or from the lens barrel The method of attaching the whole accessory through the adapter ring and tightening and stopping is used.

[0005]

In the conventional filter holder, the wall surface of the opening of the filter holder comes into contact with the surface of the filter when the filter is inserted and removed, and therefore, when the insertion and removal of the sheet-shaped filter is repeated, the surface of the filter is removed. There was a problem that it was scratched and could not be used within a short period of time.

In order to prevent scratches on the filter surface at this time, a method of using an accessory that is divided into two members, a front frame and a rear frame, is a method in which the lens barrel is attached to the camera body and the tip of the lens barrel is attached. There was a problem that the filter could not be replaced quickly when the accessory was attached to the.

Further, as a method of mounting the accessory on the lens barrel, by tightening only the tightening member of the accessory main body on the outer periphery of the adapter ring, when the tightening member is slightly loosened, a little unexpected force is applied to the adapter main body. However, there was a drawback that the accessory itself would come off the adapter ring.

According to the present invention, when a filter is removably housed and held in a predetermined housing and attached to a part of the lens barrel,
By properly setting the structure of the housing, the filter can be replaced quickly, the filter surface is not easily scratched when the filter is attached and detached, and the filter does not easily come off from the inside of the housing and is stable. An object of the present invention is to provide a filter holder that can be stored and held, and an optical device auxiliary device using the filter holder.

[0009]

In a lens barrel of the present invention, (1-1) a front frame (1) having a predetermined opening and a rear frame (2) are arranged to face each other, and the front frame and the rear frame are arranged. When the filter is inserted through the insertion opening (103) formed between the first frame and the rear frame, the first stepped portions (1a, 2a) around the openings of the front frame and the rear frame contact the peripheral part of the filter. A filter holder (101) held so as to be in contact with each other, wherein the front frame and the rear frame have a second step portion (1b, 1b, which is recessed from the first step portion in the central direction in the cross section). 2b), a part of the insertion opening (103) covers a region of the insertion opening, and a movable shielding means (7, 7) for limiting insertion and removal of the filter.
9) and the front frame or the rear frame is provided with a fitting portion (2e) for fitting with another lens barrel member.

In particular, (1-1-1) the other lens barrel member is a lens barrel (102) or an adapter ring (4).

(1-1-2) The amount of depression of the second step portion should be such that when the filter is inserted, it does not come into contact with the filter.

(1-1-3) The shielding means has a driving member (7) which is reciprocally driven in the optical axis direction to shield a part of the insertion opening.

(1-1-4) A hood attaching / detaching means (1d) for attaching / detaching the hood (3) is provided on a part of the front frame or the rear frame.

(1-1-5) The hood attaching / detaching means uses a screw member or a bayonet.

(1-1-6) The front frame or the rear frame is provided with a lock means (11) for connecting and fixedly holding another lens barrel member. And so on.

(1-2) When a front frame and a rear frame having a predetermined opening are arranged so as to face each other, and a filter is inserted through an insertion opening formed between the front frame and the rear frame, the front frame And the first stepped portion around the opening of the rear frame and the peripheral portion of the filter are held in contact with each other.

In the optical device auxiliary device of the present invention, (2-1) a front frame having a predetermined opening and a rear frame are arranged to face each other,
When the filter is inserted through the insertion opening formed between the front frame and the rear frame, the first stepped portion at the peripheral portion of the opening of the front frame and the rear frame and the peripheral portion of the filter come into contact with each other. In the cross section, the front frame and the rear frame have a second stepped portion that is recessed from the first stepped portion toward the center of the first stepped portion, and a part of the insertion opening is An adapter ring is detachably provided on one of the front frame and the rear frame of the filter holder, which covers a region of the insertion port and is provided with a movable shielding means for restricting insertion and removal of the filter, and a hood is detachably provided on the other. It is characterized by being.

[0018]

1 (A) and 1 (B) show the case where the optical device auxiliary apparatus of the present invention is mounted on a lens barrel when viewed from the rear (image side) and the front (object side). FIG. 2 is a perspective view of a main part when the optical member holding device of the present invention is mounted on a lens barrel, and FIG. 3 is a main part when the optical member holding device of the present invention is mounted on a lens barrel. 4 is a plan view, FIG. 4 is a partial cross-sectional view of a part of the optical member holding device of the present invention mounted on a lens barrel, and FIG. 5 is a partial view of the optical member holding device of the present invention mounted on a lens barrel. FIG.

In the figure, 101 is a filter holder,
A filter (not shown) is inserted and removed through an insertion opening 103 formed between the front frame 1 and the rear frame 2. Reference numeral 3 denotes a hood, which is detachably provided on the inner diameter portion of the front frame 1 forming the filter holder 101 by using a screw member, a bayonet or the like. Reference numeral 4 denotes an adapter ring, which is located between the rear frame 2 of the filter holder 101 and the lens barrel 102 and is used to connect the two. The filter holder 101, the adapter ring 4, and the hood 3 form an optical device auxiliary device.

The front frame 1 includes a first shelf (first step portion) 1a,
It has a second shelf (second step portion) 1b recessed from it, and the rear frame 2 has a first shelf (first step portion) 2a and a second shelf recessed from it (second step portion). 2b. The front frame 1 and the rear frame 2 form a part of a housing for storing a filter, and a filter is provided by opening a space between the first shelf 1a of the front frame 1 and the first shelf 2a of the rear frame 2. An insertion port 103 for insertion / removal is formed. The front frame 1 and the rear frame 2 form one element of the housing,
A sheet-like filter (not shown) is inserted into and removed from an insertion opening 103 provided between the first shelf 1a of the front frame 1 and the first shelf 2a of the rear frame 2 in the area 104 sandwiched between the two.

At this time, the peripheral portion of the sheet filter is
It is inserted while rubbing the first shelf 1a of the front frame 1 and the first shelf 2a of the rear frame 2. Since the first shelf 1a and the second shelf 1b are provided with a step, the central portion (effective surface) of the sheet filter should rub against the wall surfaces of the front frame 1 and the rear frame 2 when the sheet filter is inserted. There is no. The sheet filter is inserted between the front frame 1 and the rear frame 2, and the bottom face portion 2d of the rear frame 2 is inserted.
It abuts and is stored.

After the filter is housed in the space 104 in the housing from the insertion opening 103 in this way, the front frame 1 and the rear frame 2
The first stepped portion (corresponding to 1a, 2a) around the opening of the filter and the peripheral portion of the filter are held in contact with each other in the space 104 stably.

The second shelf 1b of the front frame 1 has an opening 1c, and the second shelf 2b of the rear frame 2 has an opening 2c.
The openings 1c and 2c are composed of extremely small planes and slopes, and have a structure for preventing harmful light due to reflection. A filter screw part (hood attaching / detaching means) is provided on the inner diameter of the opening of the front frame 1.
1d is formed and is a hood 3 for blocking harmful light
Can be screwed together. A fitting portion 2e for fitting the outer diameter of the adapter ring 4 to the inner diameter of the rear frame 2
have. A C ring 5 is fitted to the fitting portion 2e of the rear frame 2. Further, a C cover 6 which is a plate for preventing the C ring 5 from coming off is screwed to the C ring 5. C
The inner diameter portion of the cover 6 is structured to fit with the outer diameter of the adapter ring 4.

A hole 2f is provided in the rear frame 2 at a position outside the opening 2c, and a pin (driving member) 7 is inserted into the hole 2f with a spring 8 interposed therebetween. The pin 7 is provided with a screw hole, and the knob 9 is screw-connected with the rear frame 2 sandwiched therebetween. The pin 7 and the knob 9 constitute one element of the shielding means for inserting and removing the filter.

The pin 7 and the knob 9 are constantly pressed toward the front frame 1 by the compressed spring 8. Rear frame 2
An oval-shaped hole is machined in the hole 2f of 2 and fitted with the oval-shaped machined into the pin 7. Therefore, the pin 7 and the knob 9 cannot rotate when being pressed in the direction of the front frame 1.

The pin 7 has a shaft portion having a smaller diameter than the oval shape formed adjacent to the oval shape. When the knob 9 is pulled and overlaps with the oval shape portion of the hole 2f of the rear frame 2, the knob 9 is pulled. And the pin 7 can freely rotate.

If the knob 9 is rotated 90 ° while the knob 9 is rotatable, the oval phase shifts and the pin 7
The oval-shaped part can be mounted on and fixed to the shelf of the rear frame 2. At this time, the tip portion of the pin 7 enters into the hole 2f of the rear frame 2 and the space between the front frame 1 and the rear frame 2 (insertion port 103).
It does not stick out.

The pin 7 is reciprocally driven in the optical axis direction to open and close a part of the insertion opening 103 to insert and remove the filter. Further, when the filter is inserted, the pin 7 prevents the filter from falling out of the housing.

A nut 1 is attached to the rear frame 2 by a C cover 6.
0 is embedded, and a lock knob (lock means) 11 is screwed into the nut 10. The C-ring 5 is in contact with the tip of the lock knob 11 and
The C ring 5 is rotated and fed out to push in the C ring 5 so that the C ring 5 bites into the groove portion 4a provided on the outer peripheral portion of the adapter ring 4. Thereby, the adapter ring 4 and the rear frame 2 are connected and fixed. The groove 4
The width a is wider than the width of the C ring 5.

The inner diameter of the adapter ring 4 has a threaded portion 4b.
Is processed, and the tip outer peripheral portion 10 of the lens barrel 102 is processed.
2a can be screwed together. It is also possible to screw in a commercially available accessory such as a glass filter. The second outer diameter portion 4c of the adapter ring 4 is threaded so as to be screwed with the lens barrel 102.

As described above, in the present embodiment, the filter holder 101 has an opening formed of two wall surfaces, a plurality of steps are provided on the inner diameter side of the wall surface, and the wall surface with a wide opening ( 1b, 2b) is provided with an opening diameter larger than the effective diameter of the filter, and the lens barrel 1 is provided on the first wall portion 2.
02 has a fitting diameter for attaching the adapter ring 4 for coupling with 02, and the second wall surface portion 1 has a structure portion for attaching the hood 3 for shielding harmful light, and the filter and the adapter 101. The outer peripheral surface of the adapter ring 4 for coupling with the lens barrel 102 has a groove portion 4a wider than the width of the tightening member (C ring 5) provided in the filter adapter 101.
In the inner diameter part of the adapter ring 4 for connecting with 2,
It is configured to have a screw portion.

In the first embodiment, a groove is formed in the outer diameter of the adapter ring 4 so that the adapter ring 4 can be attached by tightening the C ring 5. However, the same effect can be obtained with the following configuration. A plurality of claw portions are provided on the outer peripheral portion of the adapter ring 4, and a plurality of groove portions are formed in the inner diameter portion of the rear frame 2 so that the claws of the adapter ring 4 can be fitted to each other, and bayonet coupling is performed. A plurality of claw portions are provided on the outer peripheral portion 102a of the front end of the lens barrel 102, and the adapter ring 4 is attached to the inner diameter portion of the rear frame.
A plurality of groove portions are provided so that the claws of the above are fitted to each other, and the bayonet coupling is performed. The inner frame screw portion of the front frame 1 has a plurality of groove shapes instead of the screws, and the rear end portion of the hood 3 is provided with a plurality of claws that fit into the groove portions to be bayonet-coupled. Etc. may be used.

[0033]

As described above, according to the present invention, when the filter is removably accommodated and held in a predetermined housing and attached to a part of the lens barrel, the structure of the housing is appropriately set. By doing so, the filter can be exchanged quickly, the filter surface is not easily scratched when the filter is attached and detached, and the filter holder can be stably stored and held without easily coming off from the inside of the housing, An optical device auxiliary device using the same can be achieved.

In particular, according to the present invention, it is possible to easily insert and remove the sheet-shaped filter when the sheet-shaped filter to be inserted into the optical device auxiliary device is mounted, and the effective diameter portion of the sheet-shaped filter is not easily scratched. An optical device auxiliary device can be provided, and an optical device auxiliary device that can be fixed at an arbitrary angle with a structure that does not easily fall off due to external force can be configured.

[Brief description of drawings]

FIG. 1 is a perspective view of essential parts when the optical device auxiliary device of the present invention is attached to a lens barrel when viewed from the rear (image side) and the front (object side).

FIG. 2 is a sectional view of an essential part when the optical member holding device of the present invention is attached to a lens barrel.

FIG. 3 is a plan view of essential parts when the optical member holding device of the present invention is attached to a lens barrel.

FIG. 4 is a partial cross-sectional view of a main part when the optical member holding device of the present invention is attached to a lens barrel.

FIG. 5 is a partial cross-sectional view of a main part when the optical member holding device of the present invention is attached to a lens barrel.

[Explanation of symbols]

 101 filter holder 102 lens barrel 103 insertion opening 104 space 1 front frame 2 rear frame 3 hood 4 adapter ring 5 C ring 1a, 2a first step 1b, 2b second step 7 pin 9 knob 11 locking means

Claims (9)

[Claims] 1. A front frame and a rear frame, wherein a front frame and a rear frame having a predetermined opening are arranged to face each other, and a filter is inserted through an insertion opening formed between the front frame and the rear frame. Is a filter holder that holds the first step portion around the opening of the filter and the peripheral portion of the filter in contact with each other, wherein the front frame and the rear frame are in a central direction from the first step portion in the cross section. A second stepped portion that is recessed from the first stepped portion, a part of the insertion opening covers a region of the insertion opening, and movable shield means for limiting insertion and removal of the filter; A filter holder, characterized in that the front frame or the rear frame is provided with a fitting portion for fitting with another lens barrel member. 2. The filter holder according to claim 1, wherein the other lens barrel member is a lens barrel or an adapter ring. 3. The filter holder according to claim 1, wherein the amount of depression of the second step portion is such that it does not come into contact with the filter when the filter is inserted. 4. The shield means is reciprocally driven in the optical axis direction,
The filter holder according to claim 1, further comprising a driving member that shields a part of the insertion opening. 5. The filter holder according to claim 1, wherein a hood attaching / detaching means for attaching / detaching a hood is provided on a part of the front frame or the rear frame. 6. The filter holder according to claim 5, wherein the hood attaching / detaching means uses a screw member or a bayonet. 7. The filter holder according to claim 1, wherein the front frame or the rear frame is provided with lock means for connecting and fixing and holding to another lens barrel member. 8. A front frame and a rear frame when a front frame and a rear frame having a predetermined opening are arranged to face each other and a filter is inserted through an insertion opening formed between the front frame and the rear frame. A filter holder, characterized in that the first step portion at the periphery of the opening and the peripheral portion of the filter are held in contact with each other. 9. A front frame and a rear frame, wherein a front frame and a rear frame having a predetermined opening are arranged to face each other, and a filter is inserted through an insertion opening formed between the front frame and the rear frame. The first step portion of the opening peripheral portion and the peripheral portion of the filter are held in contact with each other, and the front frame and the rear frame have the first
A second step portion that is recessed from the first step portion in the central direction from the step portion, and a movable portion that covers a region of the insertion opening in a part of the insertion opening and limits insertion and removal of the filter. 2. An optical device auxiliary device, characterized in that an adapter ring is detachably provided on one of the front frame and the rear frame of the filter holder provided with the shielding means and the hood is detachably provided on the other.