JP2003195139A - Lens barrel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To facilitate focusing by providing a lens barrel with a focusing point position for normal photography and a close-up photography (macrophotography). <P>SOLUTION: This lens barrel is provided with a guide shaft 40 guiding a lens holding frame 30 in the optical axis direction with respect to a base 10 and a spring 50 energizing the frame 30 to the base 10 side, and an adjusting plate 61 having an engaging hole 61a in which the projecting piece 35 of the frame 30 is engaged is arranged to move in the optical axis direction L on the outer wall surface of a cover housing 20. After performing focusing by adjusting the position of the plate 61, the plate 61 is fixed by a tightening screw 62. The hole 61a is provided with a front edge 61a" regulating the piece 35 to the focusing point position at the time of macrophotography. Thus, the focusing is facilitated, and an excellent picture in focus can be obtained both in normal photography and the macrophotography. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens barrel mounted on a digital camera or the like, and more particularly to a lens barrel equipped with a mechanism for adjusting the focus of a lens when assembled.

[0002]

2. Description of the Related Art As a conventional lens barrel mounted in a digital camera or the like, one focus fixed with respect to an image pickup surface (CCD), that is, an object at a distance of several meters or more is taken. ) A lens barrel with a single focal point that is well known is known. In the assembling of the lens barrel, first, the lens is appropriately moved back and forth in the optical axis direction with respect to the image pickup surface of the image pickup device (CCD) to perform focusing (focus adjustment), and then the lens does not move. As described above, the lens is assembled by being completely fixed to the lens frame or the like with an adhesive or the like.

[0003]

Therefore, in the conventional lens barrel, if the focal position with respect to the image pickup surface deviates for some reason after fixing the lens completely, disassemble and reassemble or There was no method other than discarding the above, and it took time for reassembling or wasting parts. Further, in a digital camera or the like equipped with the above-mentioned monofocal lens barrel, when close-up photography (macro photography) for photographing a subject approaching within several tens of centimeters (for example, about 30 cm) is performed, it is monofocal. There is an inconvenience that a taken image is blurred and a good taken image cannot be obtained.

The present invention has been made in view of the above problems of the prior art. The object of the present invention is to easily perform focusing at the time of assembling, and also to perform refocusing after assembling. Another object of the present invention is to provide a lens barrel that is easy to perform and that can provide good captured images even in close-up photography (macro photography).

[0005]

The lens barrel of the present invention comprises:
A cover casing that has a base that defines the position of the imaging surface, a lens holding frame that holds the lens, and an opening that opens toward the subject side and that is detachably connected to the base so as to cover the lens holding frame. A lens barrel including a body, a guide member for movably guiding the lens holding frame in the optical axis direction, a spring for urging the lens holding frame to one side in the optical axis direction, and a lens holding frame. Adjusting means for moving and moving the optical element in the direction of the optical axis against the biasing force of the spring to adjust and hold it at a predetermined position. According to this configuration, in the state in which the lens holding frame is movably supported by the guide member, the adjusting means resists the urging force of the spring to position the lens holding frame at a predetermined position (that is, when performing normal photographing). Focusing can be easily performed by adjusting and holding (for example, fastening, latching, etc.) the focus position with respect to the imaging surface. Also, even after assembly
The focus can be easily readjusted by appropriately adjusting the adjusting means.

In the above structure, the lens holding frame has a projecting piece projecting to the outside of the cover housing so as to be movable in the optical axis direction, and the adjusting means has an engaging portion for engaging the projecting piece. It is possible to adopt a configuration including an adjusting plate that is movably supported in the optical axis direction and a fastening member that fastens the adjusting plate at a predetermined position. With this configuration, when the adjustment plate is moved in the optical axis direction while the lens holding frame is movably supported by the guide member, the protruding piece moves in the optical axis direction via the engaging portion. Then, when the lens is focused on the imaging surface, a fastening member (for example, a fastening screw)
The lens holding frame (lens) is held at the in-focus position by fastening the adjusting plate with. As described above, the use of the adjusting plate facilitates focusing.

In the above structure, the engaging portion is an engaging hole having a restricting edge capable of restricting the protruding piece at the focal position when the protruding piece is inserted so as to be movable within a predetermined range in the optical axis direction. , Configuration can be adopted. According to this configuration, when the adjusting plate moves the projection piece until it is regulated by the regulation edge of the engagement hole (for example, by the switching lever on the camera side) in a state of being focused on when performing normal photographing, , The lens is positioned at the in-focus position when performing close-up photography (macro photography). As a result, a good captured image can be obtained in close-up photography. Further, by providing the regulating edge for regulating the focal position at the time of close-up in the engaging hole of the adjusting plate, the structure can be simplified as compared with the case where it is provided separately.

In the above structure, the adjusting plate may have an adjusting hole into which an adjusting tool for moving in the optical axis direction is inserted. According to this configuration, by inserting an adjusting tool (for example, an eccentric screwdriver) into the adjusting hole and rotating the adjusting plate, the adjusting plate can be moved while being finely adjusted in the optical axis direction, and focus adjustment can be performed easily and easily. It can be performed with high accuracy.

In the above structure, the cover housing may have a guide portion on its outer wall surface for supporting and guiding the adjusting plate, and the adjusting plate may be arranged in the vicinity of the guide member. According to this configuration, with respect to the base,
After the guide member, the lens holding member, and the cover housing are assembled, the adjustment plate can be attached so as to be supported by the guide portion on the outer wall surface of the cover housing. Therefore,
After the entire assembly is completed, the focus can be easily adjusted only by adjusting the adjusting plate from the outside. Further, by disposing the adjusting plate in the vicinity of the guide member, even if a force is applied to the adjusting plate during adjustment, it is possible to smoothly perform focus adjustment while preventing the lens from falling.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 7
1 shows an embodiment of a lens barrel according to the present invention. FIG. 1 is a front view, FIG. 2 is a front view showing the inside, FIG. 3 is a side view, and FIGS. 4 and 5 are sectional views showing the inside. FIG. 6 is a plan view showing the adjustment plate, and FIG. 7 is a side view showing the outer wall surface of the cover housing.

As shown in FIGS. 1 to 3, the lens barrel includes a base 10 that defines the position of the image pickup surface, and a cover housing 20 that is detachably connected to the base 10.
A lens holding frame 30 for holding the lens G, a guide shaft 40 as a guide member for movably guiding the lens holding frame 30 in the optical axis direction L, and a lens holding frame 30 rearward (one side) in the optical axis direction. A spring 50 that urges the lens holding frame 30 and an adjusting unit 60 that adjusts the position of the lens holding frame 30 in the optical axis direction L are formed.

As shown in FIGS. 4 and 5, the base 10 cooperates with the cover housing 20 to define an internal space on the front side thereof, and has a glass plate 100 and an imaging surface on the rear side thereof. It holds an image sensor (CCD) 110. That is, the base 10 defines the position of the imaging surface, and thus serves as a reference for assembling the lens holding frame 30, the cover housing 20, and the like. On the front side of the base 10,
A guide shaft 40 and a detent shaft 41 extending in the optical axis direction are coupled.

As shown in FIGS. 4 and 5, the lens holding frame 30 holds a plurality of lenses G, and a shutter mechanism 32 that opens and closes and squeezes an opening 31 for exposure in a substantially intermediate region in the optical axis direction L. Holding In the lens holding frame 30,
As shown in FIGS. 2 and 5, the connecting portions 33 and 34 are integrally formed, and the connecting portions 33 and 34 are slidably connected to the guide shaft 40 and the detent shaft 41. The lens holding frame 30 is guided so as to reciprocate in the optical axis direction L while being restricted from rotating about the optical axis. Further, as shown in FIG. 4, the lens holding frame 30 is integrally formed with a protruding piece 35 that protrudes to the outside of the cover housing 20. As shown in FIGS. 1 and 4, a switching lever A provided on the camera side is engaged with the projecting piece 35.

The spring 50, as shown in FIG.
It is stretched between the hooking piece 11 of 0 and the hooking piece 36 of the lens holding frame 30, and urges the lens holding frame 30 toward the base 10 (to the rear side in the optical axis direction L). There is. And
In a state before adjustment by the adjusting means 60, the connecting portion 33 of the lens holding frame 30 is urged by the urging force of the spring 50.
The lens holding frame 30 is held at the position where the rear end surface 33a contacts the front surface 12 of the base 10.

As shown in FIGS. 1, 4 and 5, the cover housing 20 has an opening 21 that opens toward the subject side and a protruding piece 35 that is movable in a predetermined range in the optical axis direction L. It has a notch hole 22 for making it, an end face 23 for positioning in the optical axis direction L when assembled to the base 10, etc., and as a whole, cooperates with the base 10 to cover the lens holding frame 30, the spring 50, etc. Has been formed.

After the cover housing 20 is assembled to the base 10, the cover housing 20 is fastened from the back surface side of the base 10 by screws (not shown) to be firmly connected to the base 10. That is, it is detachable from the base 10 and can be easily disassembled by removing the screws.

Further, as shown in FIG. 6, the cover housing 20 has an outer wall surface 20a on which an adjusting plate 61, which will be described later, is provided.
A guide portion 24 that supports and guides in the optical axis direction L is formed. The guide portion 24, as shown in FIG.
It is composed of a flat support surface 24a formed so as to surround the notch hole 22 through which the hole is inserted, four projections 24b for guiding both side edges of the adjusting plate 61, and two guide pins 24c. Further, in this region, a female screw portion 25 into which a fastening screw 62 described later is screwed, and an insertion hole 26 into which an adjusting tool such as an eccentric driver is inserted are formed.

As shown in FIG. 3, the adjusting means 60 comprises an adjusting plate 61 and a fastening screw 62 as a fastening member for fixing the adjusting plate 61 to the cover housing 20. As shown in FIGS. 3 and 7, the adjusting plate 61 has a substantially rectangular shape that is long in the optical axis direction L, and has an engaging hole 61a as an engaging portion for engaging the protruding piece 35 and a guide pin 24c. Two elongated holes 61b to pass through, an adjusting hole 61c into which an adjusting tool is inserted,
It has a substantially rectangular screw hole 61d for passing the fastening screw 62 and the like.

The engaging hole 61a formed in the adjusting plate 61 is
As shown in FIGS. 3 and 7, it has a rectangular shape and is formed to have an opening length H2 wider in the optical axis direction L than the thickness H1 of the protruding piece 35. That is, as shown in FIG. 7, the engagement hole 61 a is formed in the rear end surface 35 of the protruding piece 35.
a rear edge 61a 'with which a abuts, and the front end face 3 of the protruding piece 35.
It is formed so as to define a front edge 61a ″ as a regulation edge with which 5b abuts.

Here, the opening length H2 of the engaging hole 61a is
From the state where the normal imaging is focused on the imaging surface and the rear end surface 35a of the projecting piece 35 is in contact with the rear edge 61a ', the projecting piece 35 moves forward by a predetermined distance (H2-
H1) is moved so that when the front end surface 35b comes into contact with the front edge (regulating edge) 61a ″, the lens holding frame 30 (lens G) is positioned at the focus position of close-up photography (macro photography). Has been formed.

The adjusting plate 61, as shown in FIG.
It is movably supported in the optical axis direction L at a position away from the guide shaft 40 by a distance D, and is disposed near the guide shaft 40 in comparison with the entire configuration. Therefore, an adjusting force is exerted on the adjusting plate 61 to move the lens holding frame 30 through the protruding piece 35 in the optical axis direction L.
The bending moment generated by the adjusting force when the lens is moved to is relatively small, and the tilt of the lens G is prevented as much as possible. As a result, the focus can be smoothly adjusted.

Next, the procedure for assembling the lens barrel, the focus adjustment and the operation will be described. First, the plurality of lenses G are assembled to the lens holding frame 30, and the distance between the lenses G and the optical axis and the like are adjusted as one module by only this. Each lens G is detachably incorporated in the lens holding frame 30.

Next, the guide shaft 40 and the detent shaft 41 are firmly connected to the base 10, and then the lens holding frame is inserted so that the guide shaft 40 and the detent shaft 41 are passed through the connecting portions 33 and 34. 30 is assembled. Accordingly, the lens holding frame 30 is supported so as to be reciprocally movable in the optical axis direction L while being restricted from rotating about the optical axis. The detent shaft 41 may be fixed to the cover housing 20 in advance.

Subsequently, a spring 50 is stretched between the hooking piece 11 of the base 10 and the hooking piece 36 of the lens holding frame 30. As a result, the lens holding frame 30 is pulled rearward in the optical axis direction L, and is held in a state in which the rear end surface 33a is in contact with the front surface 12 of the base 10.

Subsequently, the cover housing 20 is attached from the front side in the optical axis direction L so as to cover the whole body, and the base 10 is attached.
Is positioned by contacting with, and is fastened from the back side of the base 10 with a screw, and is firmly connected to the base 10.
In this assembly, the cover housing 20 is assembled so that the projecting piece 35 of the lens holding frame 30 projects from the cutout hole 22.

Subsequently, the adjusting plate 61 is arranged in the area of the guide portion 24 which forms a part of the outer wall surface 20a of the cover housing 20. That is, the adjusting plate 61 is arranged inside the four protrusions 24b, and the guide pins 24 are provided in the two long holes 61b.
It is arranged on the support surface 24a so that c is inserted and the projecting piece 35 is inserted into the engagement hole 61a.

Next, the fastening screw 62 is inserted from the outside of the adjusting plate 61 into the screw hole 61d and screwed halfway into the female screw portion 25 of the cover housing 20, so that the adjusting plate 61 is movable. Held in.

Subsequently, an eccentric driver as an adjusting tool is inserted from the outside of the adjusting plate 61 into the adjusting hole 61c, and its tip is inserted into the insertion hole 26 of the cover housing 20.
Then, by rotating the eccentric driver while engaging the eccentric portion of the eccentric driver with the inner edge portion of the adjustment hole 61c, the adjustment plate 61 moves finely toward the front side in the optical axis direction L. Let

At this time, the rear edge 61a 'of the engaging hole 61a.
Moves the protruding piece 35 to the front side in the optical axis direction L against the biasing force of the spring 50. Then, when the lens G is focused on the image pickup surface, the fastening screw 62 is screwed in to firmly fasten the adjusting plate 61. This completes the focus adjustment of the lens for normal shooting. After the adjustment, if a defocus occurs, the fastening screw 62
The adjustment plate 61 can be adjusted by loosening, and the adjustment can be performed again using an eccentric screwdriver or the like.

In this way, the lens holding frame 30 is attached to the spring 50.
The adjusting means 60 (adjusting plate 61, fastening screw 6) capable of moving in the optical axis direction L against the biasing force of the
By adopting 2), focusing can be easily performed, and even when defocus occurs after assembly, readjustment can be easily performed without damaging the parts.

In the lens barrel in which the assembling and focus adjustment are completed, as shown in FIGS. 3 and 7, the protruding piece 35 is held in a state of being engaged with the rear edge 61a 'of the engaging hole 61a. . In this state, the image is in focus with respect to normal shooting (normal shooting for shooting a subject several meters or more away). Therefore, in normal photographing, a good photographed image in focus can be obtained.

On the other hand, the projecting piece 35 is moved to the front side in the optical axis direction L by the switching lever A of the camera, and the engaging hole 6
When it is held in a state of being engaged with the front edge (regulating edge) 61a ″ of the la 1a, a close-up shot (macro shooting) for shooting a subject within a range of several tens of centimeters is in focus. Therefore, in close-up photography (macro photography), a good photographed image in focus can be obtained.

As described above, with respect to the lens barrel which basically has the structure of a single focus lens, the guide shaft 40,
By adopting the adjusting means 60 (adjusting plate 61, fastening screw 62), focus adjustment becomes easy, and the switching operation is performed only by the switching lever A, so that both normal shooting and close-up shooting (macro shooting) can be performed. A good captured image in focus can be obtained.

In the above embodiment, the adjusting plate 61 and the fastening screw 62 which can reciprocate linearly in the optical axis direction L are shown as the adjusting means 60 for adjusting the focus, but the adjusting means 60 is not limited to this. Instead, a portion where the protruding piece 35 is engaged is formed on a part of the rotating plate, and the position of the protruding piece 35 in the optical axis direction L is adjusted by adjusting the rotation angle of the rotating plate. It may be.

Further, in the above embodiment, as the spring for urging the lens holding frame 30 to one side in the optical axis direction L,
Although the spring 50 that urges toward the rear in the optical axis direction L is shown, the present invention is not limited to this, and a compression spring that urges toward the front side in the optical axis direction L is adopted, and the projecting piece 35 is moved forward. By moving from the side to the rear side, the focal point position on the close-up (macro photographing) side may be adjusted to the focal point position on the normal photographing side.

Further, in the above embodiment, the adjusting means 60 (adjusting plate 61, fastening screw 62) is attached to the cover housing 20.
However, the present invention is not limited to this, and the adjusting means 60 may be supported by a part of the base 10.

[0037]

As described above, according to the lens barrel of the present invention, the guide member and the lens for guiding the lens holding frame movably in the optical axis direction with respect to the base defining the position of the image pickup surface. A spring that biases the holding frame to one side in the optical axis direction,
Since the lens holding frame is provided with an adjusting means that moves the lens holding frame in the optical axis direction against the biasing force of the spring to adjust and hold the lens holding frame at a predetermined position, focusing can be easily performed at the time of assembling and Even afterward, the readjustment of the focus can be easily performed. In particular, the adjusting means is composed of the adjusting plate arranged to be movable in the optical axis direction by engaging the protruding piece of the lens holding frame protruding to the outside of the cover housing, and the fastening member for fastening the adjusting plate. The structure can be simplified. Furthermore, the adjustment plate is provided with an engaging hole that has a regulation edge for positioning during close-up photography (macro photography), so that both normal photography and close-up photography (macro photography) are in good focus. It is possible to obtain various captured images.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of a lens barrel according to the present invention.

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

FIG. 3 is a side view of the lens barrel shown in FIG.

FIG. 4 is a cross-sectional view of the lens barrel shown in FIG.

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

FIG. 6 is a side view of a cover housing.

7 is a plan view showing an adjusting plate 61. FIG.

[Explanation of symbols]

10 base 11 hanging piece 20 cover housing 20a outer wall surface 21 opening 22 Notch hole 24 (24a, 24b, 24c) Guide part 24a support surface 24b protrusion 24c guide pin 25 screw holes 26 insertion holes 30 lens holding frame 33, 34 connecting part 35 protruding piece 36 Hook 40 Guide shaft (guide member) 41 Non-rotating shaft 50 springs 60 Adjustment means 61 Adjusting plate (adjusting means) 61a Engagement hole (engagement part) 61a 'rear edge 61a ″ Front edge (restriction edge) 61b Guide hole 61c Adjustment hole 61d screw hole 62 Fastening screw (adjustment means) 110 image sensor (imaging surface) L optical axis direction

Claims (5)

[Claims] 1. A base that defines a position of an image pickup surface, a lens holding frame that holds a lens, and an opening that opens toward a subject side, and is attached to and detached from the base so as to cover the lens holding frame. A lens barrel including a cover housing that is freely connected, wherein a guide member for movably guiding the lens holding frame in the optical axis direction, and the lens holding frame on one side in the optical axis direction. A lens barrel including: a biasing spring; and an adjusting unit that moves the lens holding frame in the optical axis direction against the biasing force of the spring to adjust and hold the lens holding frame at a predetermined position. . 2. The lens holding frame has a protruding piece that protrudes to the outside of the cover housing so as to be movable in the optical axis direction, and the adjusting means has an engaging portion that engages the protruding piece. And an adjustment plate that is movably supported in the optical axis direction, and a fastening member that fastens the adjustment plate at a predetermined position,
The lens barrel according to claim 1, wherein: 3. The engagement portion is an engagement hole having a regulation edge capable of regulating the projection piece at a focal position when the projection piece is movably inserted in a predetermined range in the optical axis direction and a close-up image is taken. The lens barrel according to claim 2, wherein: 4. The lens barrel according to claim 2, wherein the adjusting plate has an adjusting hole into which an adjusting tool for moving in the optical axis direction is inserted. 5. The cover housing has a guide portion on an outer wall surface thereof that supports and guides the adjustment plate, and the adjustment plate is arranged in the vicinity of the guide member. The lens barrel according to any one of claims 2 to 4.