JP6529339B2 - Lens barrel and imaging device - Google Patents

Description

  The present invention relates to a lens barrel and an imaging device.

  In the lens barrel having a configuration in which the lens and the aperture plate are assembled to the lens barrel, the center of the opening of the aperture plate needs to be aligned with the optical axis of the lens. However, there are cases where the center of the aperture of the aperture plate does not coincide with the optical axis of the lens due to processing errors of the lens barrel, processing errors of the aperture plate, and the like.

  In order to solve this problem, according to Patent Document 1, even if there is a processing error, a plurality of convex portions on the inner peripheral surface of the lens barrel are engaged with a plurality of inclined portions formed on the outer periphery of the aperture plate. A lens barrel is disclosed that can align the center of the aperture of the aperture plate with the central axis of the lens barrel.

JP 2007-171726 A

  Since the lens barrel described in Patent Document 1 has a structure in which the convex portion on the inner peripheral surface of the lens barrel and the inclined portion on the outer periphery of the aperture plate are engaged, the engagement is released when a strong impact such as falling is applied. The center of the aperture of the aperture plate may be offset from the central axis of the lens barrel.

  Further, in general, in an imaging apparatus mounted in a car, it is required that a lane recognition failure such as a ghost failure does not occur in a captured moving image, for the safety security of a passenger or the like. However, in the imaging device provided with the lens barrel described in Patent Document 1, the center of the opening of the aperture plate may be shifted from the central axis of the lens barrel. Therefore, it is not sufficient from the viewpoint of preventing the occurrence of a fault, and it is difficult to use the imaging device provided with the lens barrel described in Patent Document 1 for an imaging device mounted on, for example, a car.

  The present invention has been made in view of the present situation, and it is an object of the present invention to provide a lens barrel and an imaging device capable of keeping the center of the opening of the aperture plate coincident with the central axis of the lens barrel. Do.

In order to achieve the above object, the lens barrel of the present invention is
In a lens barrel having an aperture plate with an opening formed therein, a lens and a lens barrel that houses and holds the lens and the aperture plate inside,
The inner periphery of the lens barrel has a protrusion which is raised at a predetermined height and arranged at a predetermined distance, and at least one cylindrical portion rotation stopper.
The outer periphery of the aperture plate has at least two fitting portion groups and at least one plate portion rotation stopper,
In the fitting portion group, fitting portions facing the protrusions are formed for each of the protrusions.
The distance between the fitting portion and the center of the opening is different for each of the fitting portion groups,
The lens barrel and the aperture plate are engaged with each other by engagement of the cylindrical portion rotation stopper and the plate portion rotation stopper, and by facing any one of the fitting portion groups and the projection. .

For example, at least one of the fitting portion or the protrusion has an arc end.
For example, each of the protrusions is equally formed on the inner periphery of the lens barrel, and in each of the fitting groups, each of the fitting parts is equally formed on the outer periphery of the aperture plate. .

For example, the aperture plate has a mark for identifying each of the at least two fitting portion groups.
For example, the plate portion rotation stopper is a convex portion, the cylinder portion rotation stopper is a concave portion, and the convex portion and the concave portion are formed in a substantially rectangular shape.

  An imaging device according to the present invention includes the above-described lens barrel.

  According to the present invention, the distance between the fitting portion and the center of the opening differs for each fitting portion group. Therefore, even if there is a processing error in the aperture plate and the lens barrel, one of the fitting portion groups is selected, and the selected fitting portion group and the projection face each other to make the lens barrel and the aperture diameter The board fits in with it. By this, it is possible to prevent the center axis of the lens barrel and the center of the opening of the aperture plate from shifting. Further, since the plate portion rotation stop and the tube portion rotation stop are engaged, the aperture plate does not rotate even if a strong impact is applied to the lens barrel, and the fit between the lens tube and the aperture plate is maintained . Therefore, it is possible to keep the center of the opening of the aperture plate coincident with the central axis of the lens barrel.

It is a sectional view of a lens barrel concerning an embodiment of the present invention. It is a sectional view of a lens barrel concerning an embodiment of the present invention. It is a front view of an aperture board concerning an embodiment of the present invention. It is an enlarged view of the A section shown in FIG. It is a BB sectional view shown in FIG. It is a sectional view of a lens barrel concerning an embodiment of the present invention. It is a front view of the aperture board which concerns on other embodiment of this invention. It is sectional drawing of the lens-barrel which concerns on other embodiment of this invention. It is a front view of the aperture board which concerns on other embodiment of this invention. It is sectional drawing of the lens barrel which concerns on other embodiment of this invention. It is sectional drawing of the lens barrel which concerns on other embodiment of this invention. It is sectional drawing of the lens-barrel which concerns on other embodiment of this invention. It is sectional drawing of the lens-barrel which concerns on other embodiment of this invention. It is a perspective view of an imaging device concerning an embodiment of the present invention.

  Hereinafter, a lens barrel according to a best mode for carrying out the present invention will be described with reference to the drawings.

  The lens barrel 1 according to the embodiment of the present invention has a lens barrel 2, an aperture plate 3 and lenses G1 to G4 as shown in the cross-sectional view of FIG.

  The lens barrel 2 is a substantially cylindrical member, and an optical axis AX of the lenses G1 to G4 and a center CP (see FIG. 3) of the opening 3a of the aperture plate 3 described later The lenses G1 to G4 and the aperture plate 3 are held inside so as to match with FIG. The lens barrel 2 is formed of a resin material or aluminum die casting.

  As shown in FIG. 2, three protrusions 2 b to 2 d and six tube portion rotation stoppers 2 e to 2 j are formed on the inner peripheral wall 2 a of the lens barrel 2.

  The protrusions 2b to 2d are formed to be rotationally symmetrical by 120 ° in the circumferential direction, respectively bulge from the inner peripheral wall 2a of the lens barrel 2 toward the central axis CX of the lens barrel 2 and extend in the axial direction of the lens barrel 2 It is a site. The sectional shape of the protrusions 2b to 2d is semicircular. The protrusions 2 b to 2 d are arranged on the inner circumferential wall 2 a of the lens barrel 2 at equal intervals in the circumferential direction. The protrusions 2b to 2d are formed such that the distance D from the center axis CX of the lens barrel 2 to the tip thereof has the same length d. The protrusions 2b to 2d define the position of the aperture plate 3 at three points from the circumferential direction so that the center CP of the opening 3a coincides with the central axis CX of the lens barrel 2 as described later. In the present embodiment, ± εa is set as an allowable error of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d.

  The cylindrical rotation stoppers 2e to 2j are substantially rectangular concave portions formed on the inner peripheral wall 2a of the lens barrel 2 and are formed in a groove shape along the central axis CX, and are formed on the inner peripheral wall 2a of the lens barrel 2 They are arranged at equal intervals in the circumferential direction. The cylindrical rotation stop 2e and the projection 2b, the cylindrical rotation stop 2g and the projection 2c, and the cylindrical rotation stop 2i and the projection 2d are formed adjacent to each other.

  The aperture plate 3 shown in FIG. 1 is a member that defines the aperture so as to prevent unnecessary light from entering the light receiving portion and throttles the light flux to shield the light, and is also called a light shielding plate. The aperture plate 3 is disposed between the lens G3 and the lens G4. The aperture plate 3 is a substantially circular flat plate having an opening 3a which is a circular hole at the center as shown in FIG.

  The aperture plate 3 has a plate portion rotation stopper 3b and fitting portions 3c to 3h. The plate portion rotation stopper 3 b is a substantially rectangular convex portion extending outward from the outer periphery of the aperture plate 3. The plate portion rotation stopper 3b is inserted into any of the cylinder portion rotation stoppers 2e to 2j of the lens barrel 2, and any of the cylinder portion rotation stoppers 2e to 2j engages with the plate portion rotation stopper 3b. By this, the rotation of the aperture plate 3 with respect to the lens barrel 2 is prevented. The fitting portions 3c to 3h are peripheral portions of the arc-shaped aperture plate 3 centering on the center CP of the opening portion 3a, and the relatively small diameter fitting portions 3c, 3e, 3g and the relatively large diameter The fitting portions 3d, 3f, 3h are alternately disposed.

  The small-diameter fitting portions 3c, 3e, 3g are disposed at positions of 120 ° rotational symmetry, the radius RS is the same as each other, and the fitting portions 3c, 3e, 3g form a set as a fitting portion group 3A Form The large diameter fitting portions 3d, 3f, 3h are arranged at positions of 120 ° rotational symmetry, the radius RL is the same as each other, and the fitting portions 3d, 3f, 3h form a set as a fitting portion group Form 3B.

  In the present embodiment, the design value of the radius RL of the large diameter portion fitting portions 3d, 3f and 3h is d + εa, and the design value of the radius RS of the small diameter portion fitting portions 3c, 3e and 3g is d It is assumed that-epsilon a. Further, it is assumed that the tolerances of the radii RL and RS of the fitting portions 3c to 3h are also set to ± εa. That is, in the present embodiment, the actual distance D, the radius RL, and the radius RS fluctuate within the range of ± εa around the design value d, d + εa, d−εa, respectively.

  Here, the size (2εa) of the difference between the radius RL of the large diameter fitting 3d, 3f, 3h and the radius RS of the small diameter fitting 3c, 3e, 3g is about 10 μm to 20 μm. . The magnitude of the difference between the radius RL of the large diameter fitting portions 3d, 3f and 3h and the radius RS of the small diameter fitting portions 3c, 3e and 3g may be appropriately set, and the tolerance may be set. Even in the case of being set by the relationship of [1], it is not limited to 2 [epsilon] a as in the present embodiment, and may be [epsilon] a, [epsilon] a / 2 or the like.

  Because of the arrangement structure as described above, when the plate portion rotation stopper 3b of the aperture plate 3 is inserted into any one of the cylinder portion rotation stoppers 2e, 2g and 2i adjacent to the protrusions 2b, 2c and 2d of the lens barrel 2, One of the fitting portions 3d, 3f, 3h of the fitting portion group 3B and the protrusions 2b to 2d face each other. Further, when the plate portion rotation stopper 3b of the aperture plate 3 is inserted into any one of the cylindrical portion rotation stoppers 2f, 2h, 2j, the fitting portion 3c, 3e, 3g and the projection 2b 2d oppose each other (refer FIG.4 and FIG.5).

  The lenses G1 to G4 are components for collecting light to form an image, and for example, form an image on an imaging surface of an imaging element of an imaging device to which the lens barrel 1 is attached. For example, the lens G1 is provided on the subject side and mainly functions to set an angle of view, and the lenses G2 to G4 function to maintain resolution.

  If the lens held by the lens barrel 1 satisfies desired physical properties (for example, refractive index, Abbe's number, partial dispersion ratio, linear expansion coefficient) and durability, the number of lenses, the lens material, and the lens shape It doesn't matter.

  In addition, the lens surface of the lens held by the lens barrel 1 may be formed as a spherical surface or a flat surface or an aspherical surface. When the lens surface is spherical or flat, it is preferable because lens processing and assembly adjustment can be facilitated, and changes in optical performance due to processing and assembly adjustment errors can be prevented. When the lens surface is aspheric, the aspheric surface is an aspheric surface formed by grinding, a glass mold aspheric surface formed of glass by a mold, and a composite aspheric surface formed of resin on the surface of glass. It may be any spherical surface. The lens surface may be a diffractive surface, and the lens may be a gradient index lens (GRIN lens) or a plastic lens.

  Furthermore, the lens surface of the lens held by the lens barrel 1 can be subjected to various processing on the surface of the lens body, if necessary. As an example of this processing, hydrophilization of the surface portion with a photocatalyst or the like may be mentioned in order to prevent fogging of the lens body and formation of water droplets. For example, the processing etc. which are hydrophilized with a photocatalyst etc. are mentioned with respect to the part which may be exposed outside at the time of use with an imaging device etc. etc. in order to prevent fogging of a lens main body or water droplet formation.

  Next, an assembly procedure of the lens barrel 1 according to the present embodiment will be described.

  First, the lens G4 is housed and fixed in the lens barrel 2. Next, the plate portion rotation stopper 3 b of the aperture plate 3 is inserted into any of the cylinder portion rotation stops 2 e to 2 j of the lens barrel 2, and the aperture plate 3 is accommodated in the lens barrel 2. The mounting position of the aperture plate 3 differs depending on the degree of processing error of the sizes of the lens barrel 2 and the aperture plate 3.

  Here, first, in order to facilitate understanding, no processing error occurs in the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d, and the fitting of the large diameter portion of the aperture plate 3 A case where a processing error ε occurs in the radius RL of the portions 3d, 3f, 3h and the radius RS of the fitting portions 3c, 3e, 3g of the small diameter portion will be described.

  In this case, first, when the aperture plate 3 is made the smallest within the range of tolerance, that is, the radius RL of the fitting portions 3d, 3f, 3h of the large diameter portion of the aperture plate 3 is d, The case where the radius RS of the fitting portions 3c, 3e, 3g of the small diameter portion is d-2εa will be described.

  The plate portion rotation stopper 3b of the aperture plate 3 is inserted into any one of the cylindrical portion rotation stoppers 2e, 2g, and 2i formed adjacent to the protrusions 2b to 2d. At this time, the radius RL of the fitting portions 3d, 3f, 3h of the fitting portion group 3B is d, which is the same as the length d of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d. It is. Therefore, the lens barrel 2 and the aperture plate 3 are engaged with each other by the protrusions 2b to 2d and the fitting portion group 3B facing each other. Thus, the central axis CX of the lens barrel 2 and the center CP of the opening 3a can be made to coincide with each other.

  Further, the plate portion rotation stopper 3b is inserted into any of the cylinder portion rotation stoppers 2e, 2g, and 2i. Therefore, even if a strong impact is applied, any one of the cylindrical rotation stop 2e, 2g, 2i and the plate rotation stop 3b are engaged, and the aperture plate 3 hardly rotates. Therefore, the fit between the lens barrel 2 and the aperture plate 3 can be maintained. In FIG. 5, the plate rotation stop 3b of the aperture plate 3 is inserted into the cylinder rotation stop 2e, and the projection 2b and fitting portion 3h, the projection 2c and fitting portion 3d, and the projection 2d and fitting portion 3f. The lens barrel 2 and the aperture plate 3 are shown in cross section of the lens barrel 1 in which the lens barrel 2 and the aperture plate 3 are fitted by facing each other.

  Next, when the aperture plate 3 is made the largest within the range of tolerance, that is, the radius RL of the fitting portions 3d, 3f, 3h of the large diameter portion of the aperture plate 3 is d + 2εa. The case where radius RS of fitting part 3c, 3e, 3g is d is explained.

  The plate portion rotation stopper 3b of the aperture plate 3 is inserted into any one of the cylindrical portion rotation stoppers 2e, 2g, and 2i formed adjacent to the protrusions 2b to 2d. At this time, the radius RL of the fitting portions 3d, 3f, 3h of the fitting portion group 3B is d + 2εa, and is longer than the length d of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d. long. Therefore, even if the plate portion rotation stopper 3b is inserted into any of the cylinder portion rotation stoppers 2e, 2g, and 2i, if the aperture plate 3 is to be fitted into the lens barrel 2, the hole plate 3 is bent or the like. Therefore, it is difficult to match the central axis CX of the lens barrel 2 and the center CP of the opening 3a.

  Then, the plate portion rotation stopper 3b of the aperture plate 3 is removed from the cylinder portion rotation stoppers 2e, 2g and 2i of the lens barrel 2 and inserted into one of the cylinder rotation stoppers 2f, 2h and 2j. At this time, the radius RS of the fitting portions 3c, 3e, 3g of the fitting portion group 3A is d, which is the same as the length d of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d. It is. Therefore, the lens barrel 2 and the aperture plate 3 are engaged with each other by the protrusions 2b to 2d and the fitting portion group 3A facing each other. Therefore, the central axis CX of the lens barrel 2 and the center CP of the opening 3a can be made to coincide with each other.

  Further, the plate portion rotation stopper 3b is inserted into any one of the cylinder portion rotation stoppers 2f, 2h and 2j. Therefore, even if a strong impact is applied, any one of the cylinder rotation stop 2f, 2h, 2j and the plate rotation stop 3b are engaged, and the aperture plate 3 hardly rotates. Therefore, the fit between the lens barrel 2 and the aperture plate 3 can be maintained. In FIG. 6, the plate rotation stop 3b of the aperture plate 3 is inserted into the cylinder rotation stop 2f, and the projection 2b and fitting portion 3g, the projection 2c and fitting portion 3c, and the projection 2d and fitting portion 3e. The lens barrel 2 and the aperture plate 3 are shown in cross section of the lens barrel 1 in which the lens barrel 2 and the aperture plate 3 are fitted by facing each other.

  Next, a case where a processing error ε occurs also in the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d will be described.

  In this case, first, the processing error ε of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d and the radius RL of the fitting portions 3d, 3f, 3h of the large diameter portion of the aperture plate 3 The processing error ε of the small diameter portion and the processing error ε of the radius RS of the fitting portions 3c, 3e and 3g of the small diameter portion are all + εa.

  The plate portion rotation stopper 3b of the aperture plate 3 is inserted into any one of the cylindrical portion rotation stoppers 2e, 2g, and 2i formed adjacent to the protrusions 2b to 2d. At this time, the radius RL of the fitting portions 3d, 3f, 3h of the fitting portion group 3B is d + 2εa, which is greater than the length d + εa of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d. long. Therefore, even if the plate portion rotation stopper 3b is inserted into any of the cylinder portion rotation stoppers 2e, 2g, and 2i, if the aperture plate 3 is to be fitted into the lens barrel 2, the hole plate 3 is bent or the like. Therefore, it is difficult to match the central axis CX of the lens barrel 2 and the center CP of the opening 3a.

  Then, the plate portion rotation stopper 3b of the aperture plate 3 is removed from the cylinder portion rotation stoppers 2e, 2g and 2i of the lens barrel 2 and inserted into one of the cylinder rotation stoppers 2f, 2h and 2j. At this time, the radius RS of the fitting portions 3c, 3e, 3g of the fitting portion group 3A is d, which is shorter than the length d + εa of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d. . Therefore, the aperture plate 3 can be inserted into the lens barrel 2. And either of projection part 2b-2d and any of fitting parts 3c, 3e, and 3g of fitting part group 3A respectively oppose. Further, the gap between the protrusions 2b to 2d and the fitting portions 3c, 3e, 3g of the fitting portion group 3A is εa, which is within the range of the tolerance. Therefore, the lens barrel 2 and the aperture plate 3 are engaged with each other in a close fit state. Therefore, the central axis CX of the lens barrel 2 and the center CP of the opening 3a can be made to coincide with each other.

  Further, the plate portion rotation stopper 3b is inserted into any one of the cylinder portion rotation stoppers 2f, 2h and 2j. Therefore, even if a strong impact is applied, any one of the cylinder rotation stop 2f, 2h, 2j and the plate rotation stop 3b are engaged, and the aperture plate 3 hardly rotates. Therefore, the fit between the lens barrel 2 and the aperture plate 3 can be maintained. The plate rotation stop 3b of the aperture plate 3 is inserted into the cylinder rotation stop 2f, and the protrusion 2b and the fitting portion 3g, the protrusion 2c and the fitting portion 3c, and the protrusion 2d and the fitting portion 3e face each other. By doing this, the cross section of the lens barrel 1 in which the lens barrel 2 and the aperture plate 3 engage with each other is the same as that shown in FIG.

  Next, the processing error ε of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d and the processing error of the radius RL of the fitting portions 3d, 3f, 3h of the large diameter portion of the aperture plate 3 The case where ε and the processing error ε of the radius RS of the fitting portions 3c, 3e, 3g of the small diameter portion are all −εa will be described.

  The plate portion rotation stopper 3b of the aperture plate 3 is inserted into any one of the cylindrical portion rotation stoppers 2e, 2g, and 2i formed adjacent to the protrusions 2b to 2d. At this time, the radius RL of the fitting portions 3d, 3f, 3h of the fitting portion group 3B is d, and the length d−εa of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d Longer than. Therefore, even if the plate portion rotation stopper 3b is inserted into any of the cylinder portion rotation stoppers 2e, 2g, and 2i, if the aperture plate 3 is to be fitted into the lens barrel 2, the hole plate 3 is bent or the like. Therefore, it is difficult to match the central axis CX of the lens barrel 2 and the center CP of the opening 3a.

  Then, the plate portion rotation stopper 3b of the aperture plate 3 is removed from the cylinder portion rotation stoppers 2e, 2g and 2i of the lens barrel 2 and inserted into one of the cylinder rotation stoppers 2f, 2h and 2j. At this time, the radius RS of the fitting portions 3c, 3e and 3g of the fitting portion group 3A is d-2εa, and the length d of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d -Shorter than εa. Therefore, the aperture plate 3 can be inserted into the lens barrel 2. And either of projection part 2b-2d and any of fitting parts 3c, 3e, and 3g of fitting part group 3A respectively oppose. Further, the gap between the protrusions 2b to 2d and the fitting portions 3c, 3e, 3g of the fitting portion group 3A is εa, which is within the range of the tolerance. Therefore, the lens barrel 2 and the aperture plate 3 are engaged with each other in a close fit state. Therefore, the central axis CX of the lens barrel 2 and the center CP of the opening 3a can be made to coincide with each other.

  Next, the processing error ε of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d is −εa, and the radius of the fitting portions 3d, 3f, 3h of the large diameter portion of the aperture plate 3 The case where the processing error ε of RL and the processing error ε of the radius RS of the fitting portions 3c, 3e, 3g of the small diameter portion are + εa will be described.

  The plate portion rotation stopper 3b of the aperture plate 3 is inserted into any one of the cylindrical portion rotation stoppers 2e, 2g, and 2i formed adjacent to the protrusions 2b to 2d. At this time, the radius RL of the fitting portions 3d, 3f, 3h of the fitting portion group 3B is d + 2ε, and the length d−εa of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d. Longer than. Therefore, even if the plate portion rotation stopper 3b is inserted into any of the cylinder portion rotation stoppers 2e, 2g, and 2i, if the aperture plate 3 is to be fitted into the lens barrel 2, the hole plate 3 is bent or the like. Therefore, it is difficult to match the central axis CX of the lens barrel 2 and the center CP of the opening 3a.

  Then, the plate portion rotation stopper 3b of the aperture plate 3 is removed from the cylinder portion rotation stoppers 2e, 2g and 2i of the lens barrel 2 and inserted into one of the cylinder rotation stoppers 2f, 2h and 2j. At this time, the radius RS of the fitting portions 3c, 3e, 3g of the fitting portion group 3A is d, and the length d−εa of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d Longer. Therefore, even if the plate portion rotation stopper 3b is inserted into any one of the cylinder portion rotation stoppers 2f, 2h and 2j, if the aperture plate 3 is to be fitted into the lens cylinder 2, the diameter plate 3 is bent or the like. Therefore, it is difficult to match the central axis CX of the lens barrel 2 and the center CP of the opening 3a.

  Therefore, the processing error ε of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d is -εa, and the radius RL of the fitting portions 3d, 3f, 3h of the large diameter portion of the aperture plate 3 is When the processing error ε and the processing error ε of the radius RS of the fitting portions 3c, 3e and 3g of the small diameter portion are + εa, it is assumed that the plate portion rotation stopper 3b is inserted into any of the cylinder portion rotation stoppers 2e to 2j. Also, as described above, when trying to fit aperture plate 3 into lens barrel 2, aperture plate 3 is bent or the like, so that central axis CX of lens barrel 2 and center CP of opening 3a should be aligned. Is difficult. In such a case, for example, the aperture plate 3 may be applied to the lens barrel 2 having another processing error.

  Next, the processing error ε of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d is + εa, and the radius RL of the fitting portions 3d, 3f, 3h of the large diameter portion of the aperture plate 3 And the processing error .epsilon. Of the radius RS of the fitting portions 3c, 3e and 3g of the small diameter portion are -.epsilon.a.

  The plate portion rotation stopper 3b of the aperture plate 3 is inserted into any one of the cylindrical portion rotation stoppers 2e, 2g, and 2i formed adjacent to the protrusions 2b to 2d. At this time, the radius RL of the fitting portions 3d, 3f, 3h of the fitting portion group 3B is d, which is shorter than the length d + .epsilon.a of the distance D from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b-2d. . Therefore, the aperture plate 3 can be inserted into the lens barrel 2. And either of projection part 2b-2d and any of fitting parts 3c, 3e, and 3g of fitting part group 3A respectively oppose. Further, the gap between the protrusions 2b to 2d and the fitting portions 3d, 3f, 3h of the fitting portion group 3B is εa, which is within the range of the tolerance. Therefore, the lens barrel 2 and the aperture plate 3 are engaged with each other in a close fit state. Therefore, the central axis CX of the lens barrel 2 and the center CP of the opening 3a can be made to coincide with each other.

  Further, the plate portion rotation stopper 3b is inserted into any one of the cylinder portion rotation stoppers 2e, 2g and 2i. Therefore, even if a strong impact is applied, any one of the cylindrical rotation stoppers 2e, 2g, and 2i and the plate rotation stopper 3b engage, and the aperture plate 3 hardly rotates. Therefore, the fit between the lens barrel 2 and the aperture plate 3 can be maintained. The plate rotation stop 3b of the aperture plate 3 is inserted into the cylinder rotation stop 2e, and the protrusion 2b and the fitting portion 3h, the protrusion 2c and the fitting portion 3d, and the protrusion 2d and the fitting portion 3f face each other. By doing this, the cross section of the lens barrel 1 in which the lens barrel 2 and the aperture plate 3 engage with each other is the same as that shown in FIG.

  The distance D to the tips of the protrusions 2b to 2d, the radius RS of the fitting group 3A, and the radius RL of the fitting group 3B are manufactured according to the fitting tolerance, and the lens barrel 2 and the aperture plate 3 are produced. And, so-called "fitting" is to fit together. Therefore, the central axis CX of the lens barrel 2 and the center CP of the opening 3a can be made to coincide with each other with high accuracy. Further, when the aperture plate 3 is fitted in the lens barrel 2 and it is difficult to make the central axis CX of the lens barrel 2 and the center CP of the opening 3a coincide with each other when the aperture plate 3 is bent, the fitting tolerance is A loose fit is preferred.

  Then, after the aperture plate 3 is accommodated in the lens barrel 2, the lens G 3 is accommodated in the lens barrel 2, and the aperture plate 3 is sandwiched between the lenses G 3 and G 4. Thereafter, the lens barrel 1 is assembled by storing and fixing the lenses G1 and G2 in the lens barrel 2 in the order of the lens G2 and the lens G1.

  As described above, the processing error ε of the radius RL of the fitting portions 3d, 3f, 3h of the large diameter portion of the aperture plate 3 and the processing error ε of the radius RS of the fitting portions 3c, 3e, 3g of the small diameter portion The center axis CX of the tube 2 and the center CP of the opening 3a may be shifted. Even in such a case, by inserting the plate portion rotation stopper 3b into different cylinder portion rotation stoppers 2e to 2j, any one of the fitting portion groups 3A and 3B and the projection 2b to 2d face each other, and the diameter of the lens cylinder 2 and the aperture The plate 3 can be engaged, and the central axis CX of the lens barrel 2 and the center CP of the opening 3a can be more accurately aligned.

  Further, the plate portion rotation stopper 3b is inserted into any of the cylinder portion rotation stoppers 2e to 2j. Therefore, even if a strong impact is applied, any one of the cylinder rotation stop 2e to 2j and the plate rotation stop 3b are engaged, and the aperture plate 3 hardly rotates. Therefore, the fit between the lens barrel 2 and the aperture plate 3 can be maintained.

  As mentioned above, although embodiment concerning this invention was described, a specific structure is not restricted to this embodiment, A structure is suitably changed in the range which does not deviate from the summary of this invention (a deletion of a component is also included) It is possible.

  In the above embodiment, one plate rotation stop 3b extends from the outer periphery of the aperture plate 3, but this is an example, and when the aperture plate 3 is accommodated in the lens barrel 2, the plate rotation prevention 3b is rotated by the cylinder portion The number and the position of the plate rotation stop 3b can be appropriately changed as long as the plate rotation stop 3b can be inserted into the stops 2e to 2j and the plate rotation stop 3b can be engaged with the cylinder rotation stop 2e to 2j. For example, as shown in FIG. 7, three plate portion rotation stoppers 3 b may be extended at equal intervals outward from the outer periphery of the aperture plate 3. In this case, the three plate portion rotation stoppers 3b are respectively inserted into three of the six cylinder portion rotation stoppers 2e to 2j of the lens barrel 2. Then, when the three plate portion rotation stoppers 3b are respectively inserted into any of the cylinder portion rotation stoppers 2e to 2j of the lens barrel 2, one of the fitting portion groups 3A and 3B of the aperture plate 3 and the lens barrel 2 The lens barrel 2 and the aperture plate 3 are engaged with each other by the protrusions 2b to 2d facing each other. In FIG. 8, three plate portion rotation stoppers 3b are inserted into the cylinder portion rotation stoppers 2e, 2g and 2i, and the projections 2b to 2d of the lens barrel 2 and the fitting portion group 3B of the aperture plate 3 face each other. 4 shows a cross-sectional view of the lens barrel 1 in which the lens barrel 2 and the aperture plate 3 are fitted.

  Further, as shown in FIG. 9, six plate portion rotation stoppers 3b may be extended outward from the outer periphery of the aperture plate 3 at equal intervals. In this case, the six plate portion rotation stoppers 3b are respectively inserted into any of the six cylinder portion rotation stoppers 2e to 2j of the lens cylinder 2, and one of the fitting portion groups 3A and 3B of the aperture plate 3 and the lens cylinder The lens barrel 2 and the aperture plate 3 are engaged with each other by facing the two projections 2b to 2d.

  When one or three plate rotation stoppers 3b extend outward from the outer periphery of the aperture plate 3, as shown in FIG. 3 or 7, between the fitting portions of the fitting portion groups 3A and 3B. A step S is formed. Therefore, it is possible to easily distinguish the fitting portion groups 3A and 3B. However, as shown in FIG. 9, when the six plate portion rotation stoppers 3 b extend outward from the outer periphery of the aperture plate 3, there is no step S. Therefore, there is a possibility that distinction of fitting part groups 3A and 3B can not be performed. Therefore, as shown in FIG. 9, a recess 3i is provided as a mark at the tip of the three plate rotation stoppers 3b, and the positional relationship between the recess 3i and the protrusions 2b to 2d of the lens barrel 2 You may make it distinguishable.

  Moreover, in said embodiment, although six cylinder part rotation stoppers 2e-2j were equally formed in the inner periphery of the lens cylinder 2, this is an example and plate part rotation stopper is inserted, and a cylinder part rotation stopper and a plate If the partial rotation stopper can be engaged, the number and position of the cylindrical rotation stopper can be changed as appropriate. For example, as shown in FIG. 10, only one barrel rotation stop 2e may be formed on the lens barrel 2. In this case, by reversing the aperture plate 3 having one plate portion rotation stopper 3b, different fitting portion groups 3A and 3B and the projections 2b to 2d can be opposed, and the lens barrel 2 and the aperture plate 3 And get together.

  Moreover, in said embodiment, although the cross-sectional shape of protrusion part 2b-2d was made semicircle, this is an example, and if lens cylinder 2 and aperture plate 3 can fit, it will be of projection part 2b-2d. The cross-sectional shape can be changed as appropriate. For example, as shown in FIG. 11, a triangle having an apex angle protruding toward the center of the lens barrel 2 may be taken as the sectional shape of the protrusions 2b to 2d.

  Moreover, in said embodiment, although three protrusion parts 2b-2d were formed, this is an example, and if the lens cylinder 2 and the aperture plate 3 can fit, it can change suitably. For example, four or more may be formed. In this case, the fitting portions of the fitting portion groups 3A and 3B may be formed in the same number as the protruding portions.

  Further, in the above embodiment, two fitting portion groups are formed on the aperture plate 3, but this is an example, and the lens barrel 2 and the aperture plate 3 can be appropriately changed as long as they can be engaged with each other. is there. For example, as shown in FIG. 12, three fitting portion groups may be formed. In this case, it is sufficient to form nine cylindrical rotation stops in the lens barrel 2.

  Moreover, in said embodiment, although the cross-sectional shape of cylinder part rotation stopper 2e-2j and the shape of plate part rotation stopper 3b were made into the substantially rectangle, this is an example, and either of cylinder part rotation stopper 2e-2j and a plate part If the rotation stopper 3b is engaged and rotation of the aperture plate 3 can be prevented, the cross-sectional shapes 2e to 2j of the cylindrical rotation stopper and the shapes of the plate rotation stopper 3b can be appropriately changed. For example, the cross-sectional shapes of the cylindrical rotation stoppers 2e to 2j and the shape of the plate rotation stopper 3b may be semicircular. Moreover, in said embodiment, although the cylinder part rotation stoppers 2e-2j were made into the concave part and the plate part rotation stopper 3b was made into the convex part, this is an example. For example, the cylindrical rotation stoppers 2e to 2j may be a convex portion, and the plate rotation stopper 3b may be a concave portion.

  In the above embodiment, the aperture plate 3 is used to make the central axis CX of the lens barrel 2 and the central axis CP of the opening 3a coincide with each other in one product, but this is an example. For example, the aperture plate 3 can also be used as a common part in products of different types with different distances from the central axis CX of the lens barrel 2 to the tips of the protrusions 2b to 2d.

  Moreover, in said embodiment, although the aperture plate 3 was used as the substantially circular flat plate, this is an example. The shape may be another shape, for example, a hexagonal flat plate as shown in FIG. 13 as long as it is a shape that can narrow down and block the light flux by defining the aperture so that unnecessary light does not enter the light receiving portion, and other polygons It may be a flat plate of

  In the above embodiment, the aperture plate 3 is disposed between the lens G3 and the lens G4, but this is an example. For example, an aperture plate may be disposed between the lens G1 and the lens G2 and between the lens G2 and the lens G3.

  Further, in the above embodiment, the lens barrel 2 and the aperture plate 3 are engaged by loose fitting, but this is an example. For example, when the aperture plate 3 is fitted in the lens barrel 2, the aperture plate 3 is not bent and the center axis CX of the lens barrel 2 and the center CP of the opening 3a do not deviate from each other. But it may be tight.

  Moreover, although it is suitable to use the lens-barrel 1 of this invention for the imaging device of a fixed focus, it can be used also for the imaging device which can carry out focus adjustment. Examples of this imaging device include a camera that captures a moving image, and a camera that captures a still image. Further, as shown in FIG. 14, the lens barrel 1 of the present invention can be suitably used for the in-vehicle imaging device 10. According to the in-vehicle imaging apparatus 10 having the lens barrel 1 of the present invention, there is no possibility that the center CP of the opening 3a of the aperture plate 3 deviates from the central axis CX of the lens barrel 2, It can prevent the occurrence.

  As mentioned above, although the present invention was explained in detail, the above-mentioned embodiment and modification are illustration to the last, the present invention is not limited to these, and various embodiments are possible in the range which does not deviate from the meaning of the present invention It is. In order to facilitate understanding of the present invention, the description of known technical matters has been omitted as appropriate.

DESCRIPTION OF SYMBOLS 1 lens barrel 2 lens barrel 2a inner peripheral wall 2b, 2c, 2d projection part 2e, 2f, 2g, 2h, 2i 2j tube part rotation stop 3 aperture plate 3a opening part 3b plate part rotation Stops 3c, 3d, 3e, 3f, 3g, 3e, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D, 3D Distance d from the central axis CX to the tip of the projection d: length D of the distance D, RL: radius of the fitting portion centered on the center CP of the opening

Claims (6)

In a lens barrel having an aperture plate with an opening formed therein, a lens and a lens barrel that houses and holds the lens and the aperture plate inside,
The inner periphery of the lens barrel has a protrusion which is raised at a predetermined height and arranged at a predetermined distance, and at least one cylindrical portion rotation stopper.
The outer periphery of the aperture plate has at least two fitting portion groups and at least one plate portion rotation stopper,
In the fitting portion group, fitting portions facing the protrusions are formed for each of the protrusions.
The fitting portion has a circular arc surface that is opposite to the protrusion and is centered on the center of the opening,
The radius of the circular arc surface facing the projection of the fitting portion is different for each of the fitting portion groups,
The lens barrel and the aperture plate are engaged with each other by engagement of the cylindrical portion rotation stopper and the plate portion rotation stopper, and by facing any one of the fitting portion groups and the projection. Lens barrel. It has two said fitting part groups in the outer periphery of the said aperture plate,
An arc surface opposite to the protrusion of the fitting portion in one of the fitting portions contacts the protrusion.
2. The lens barrel according to claim 1, wherein an arc surface of the other fitting portion group facing the protrusion of the fitting portion is shifted from a position in contact with the protrusion. Each of the protrusions is uniformly formed on the inner periphery of the lens barrel,
3. The lens barrel according to claim 1, wherein one of the fitting portions is uniformly formed on the outer periphery of the aperture plate in one of the fitting portion groups. 4. The diameter plate, a lens barrel according to pre-Symbol fitting portion group claim 1 having a mark for discriminating each of any one of 3. The plate portion rotation stopper is a convex portion,
The cylindrical rotation stop is a concave portion,
The lens barrel according to any one of claims 1 to 4, wherein the convex portion and the concave portion are formed in a substantially rectangular shape.   An imaging apparatus comprising the lens barrel according to any one of claims 1 to 5.