JP5183043B2 - Imaging lens and manufacturing method of imaging lens - Google Patents

Description

  The present invention relates to an imaging lens used in a video camera device, a digital camera device, and the like, and a manufacturing method of an imaging lens for manufacturing such an imaging lens.

  In recent years, video camera devices, digital camera devices, and the like have been required to further reduce the size of the device configuration, and imaging lenses used in these video camera devices, digital camera devices, and the like have also become smaller and thinner. It has been requested.

  Patent Document 1 describes an imaging lens having a first movable lens group and a second movable lens group, and an iris diaphragm mechanism disposed between the first movable lens group and the second movable lens group. The first and second movable lens groups each have a function of performing focus adjustment (focusing) and focal length adjustment (zooming) by being moved and operated in the optical axis direction. The imaging lens further includes a front group disposed closer to the subject than the first movable lens group, an intermediate group disposed in the vicinity of the iris diaphragm mechanism between the first and second movable lens groups, and Each of the rear lens groups is arranged closer to the image sensor than the second movable lens group.

  Each of these lens groups and the iris diaphragm mechanism are housed and arranged in a rectangular housing. And the 1st and 2nd movable lens group is supported by the guide shaft attached in the housing | casing so that a movement in an optical axis direction is possible in this housing | casing. Furthermore, the first and second movable lens groups are moved and operated in the optical axis direction along the guide shaft by a screw shaft that is rotated by a motor.

  The iris diaphragm mechanism is configured to have a pair of diaphragm blades that are arranged to face each other with the optical axis interposed therebetween, and each of them can be moved in the direction of contact with and away from the optical axis. These pair of diaphragm blades are moved by a diaphragm motor to adjust the aperture diameter of the through-hole formed between them and adjust the aperture ratio of the imaging lens.

  In reducing the size of such an imaging lens, the positional relationship between the moving direction of the diaphragm blades and the guide shaft becomes a problem. In other words, the pair of diaphragm blades has a width corresponding to the diameter of the light beam that passes through each lens group, and moves in a direction orthogonal to the width direction to the outer side of the diameter of the light beam that passes through each lens group. Need to be manipulated. Therefore, at least a space corresponding to the movable range of each diaphragm blade must be secured in the housing. And although a guide shaft is arrange | positioned in the movable direction of each movable lens group, ie, an optical axis direction, it cannot enter into the space equivalent to the movable range of a pair of aperture blade, and cannot arrange | position.

  That is, in the housing of the imaging lens, the movable range of the pair of diaphragm blades and the guide shaft must be arranged on the outer side of the aperture of each lens group as a positional relationship that does not interfere with each other. The space occupied by is limiting the size reduction. Further, in this imaging lens, an iris motor for moving each diaphragm blade in the iris diaphragm mechanism and a motor for rotating the screw shaft must be arranged in the housing, and these are also reduced in size. It is a factor that sets a limit.

  In the imaging lens described in Patent Document 1, the diaphragm motor is arranged at a position deviated with respect to the guide shaft, thereby reducing the size (thinning).

JP-A-5-257188

  By the way, in the imaging lens described in the above-mentioned Patent Document 1, although the position of the aperture motor is devised for miniaturization, the positional relationship between the moving direction of the aperture blade and the guide shaft is considered. Absent. That is, in this imaging lens, the guide shaft is disposed at a position that is lateral to the movable direction of each diaphragm blade, and is not sufficiently thinned in the direction orthogonal to the movable direction of each diaphragm blade. .

  Further, in this imaging lens, two shafts of a guide shaft and a screw shaft (drive shaft) are used to support one movable lens group, but the movable lens group does not contribute to driving. There is only one guide shaft that supports. The other movable lens group is supported by two guide shafts at a position deviated to one side from the movable lens group. Therefore, in this imaging lens, it is difficult to move and move each movable lens group smoothly. In particular, when moving the other movable lens group, there is a high possibility that an optical axis tilt or vibration will occur.

  Accordingly, the present invention has been proposed in view of the above-described circumstances, and includes an imaging lens having at least first and second movable lens groups and an iris diaphragm mechanism disposed between these movable lens groups. In this case, by appropriately setting the positional relationship between the guide shaft that movably supports each movable lens group and the movable range of the iris blades of the iris diaphragm mechanism, the movable lens group can be reduced in size and thickness. Is stably supported at a position sandwiching the movable lens group by at least two guide shafts, and can be smoothly moved, and the inclination and vibration of the optical axis associated with the movement operation of each movable lens group can be reduced. An object of the present invention is to provide an imaging lens in which generation is prevented.

  It is another object of the present invention to provide a method for manufacturing an imaging lens for easily manufacturing such an imaging lens.

  In order to solve the above-described problems and achieve the above object, an imaging lens according to the present invention has any one of the following configurations.

[Configuration 1]
An imaging lens having at least a first movable lens group and a second movable lens group and an iris diaphragm mechanism disposed at a predetermined position between the movable lens groups, which are disposed on the optical axis. A housing that houses the first and second movable lens groups and the iris diaphragm mechanism, and a first guide shaft that is attached to the housing and is installed in parallel to the optical axis to support the first movable lens group. A first screw shaft installed parallel to the first guide shaft and rotated by a first motor to move the first movable lens group in the direction of the optical axis, and attached to the housing to the optical axis A second guide shaft that is installed in parallel and supports the second movable lens group, and is rotated by a second motor that is installed in parallel to the second guide shaft and moves the second movable lens group in the optical axis direction. Second screen to move The first and second guide shafts are arranged at positions opposite to each other of the movable lens groups, and the first movable lens group is arranged in the optical axis direction by the first guide shaft. The second guide shaft is supported so as to be movable and is prevented from rotating around the first guide shaft, and the second movable lens group is supported by the second guide shaft so as to be movable in the optical axis direction. In addition, the first guide shaft is prevented from rotating around the second guide shaft, and the first and second screw shafts are arranged at positions opposite to each other of the movable lens groups and the first screw. The shaft is disposed at a position closer to the first guide shaft than the second guide shaft, and the second screw shaft is first than the first guide shaft. The housing is arranged at one side including a region where the first guide shaft and the first screw shaft are arranged, and the second guide shaft and the second screw shaft. A first opening portion and a second opening portion are respectively formed on the other side portion including the region to be connected, and an iris diaphragm mechanism can be inserted into the first or second opening portion, in the course of the iris diaphragm mechanism is inserted into between the groups each of the movable lens from said first or said second opening, 該虹saturation throttle mechanism the first, or the second guide shaft Avoid inserting the iris diaphragm mechanism into the housing partway, and then, when the iris diaphragm mechanism is further inserted, the iris diaphragm mechanism is orthogonal to the insertion direction so as to be moved toward the first or second guide shaft. Invite in the direction to By electrically,該虹saturation throttle mechanism guide portion is provided to by cormorants induction are disposed in the predetermined position, the first and second open portions, a first motor for supporting the first motor The lid is closed by a substrate and a second motor substrate that supports the second motor.

[Configuration 2]
In the imaging lens having the configuration 1, the iris diaphragm mechanism has one diaphragm blade and the optical axis that are movable between the optical axis and one side portion of the casing in the direction of contact with the optical axis. A pair of diaphragm blades made of the other diaphragm blades that can move in the direction of contact with and away from the optical axis with respect to the other side part, and a diaphragm motor that moves the pair of diaphragm blades. The motor is located on one side of the housing or on the other side of the housing, and is biased in a direction away from the first guide shaft or the second guide shaft. To do.

  The imaging lens manufacturing method according to the present invention has the following configuration.

[Configuration 3]
An imaging lens manufacturing method for manufacturing an imaging lens by disposing at least a first movable lens group and a second movable lens group and an iris diaphragm mechanism disposed at a predetermined position between the movable lens groups on an optical axis. Then, a first guide shaft that supports the first movable lens group is attached to the first open portion on one side of the housing that houses the first and second movable lens groups and the iris diaphragm mechanism. Inserting the first movable lens group into the housing and installing the first guide shaft parallel to the optical axis; and the second movable lens group with respect to the second open portion on the other side of the housing. The supported second guide shaft is attached, the second movable lens group is inserted into the housing, the second guide shaft is parallel to the optical axis, and each movable lens group with respect to the first guide shaft. A step of arranging at a position opposite to the first side, A step of engaging the moving lens group with the second guide shaft to prevent rotation around the first guide shaft; and a step of engaging the second movable lens group with the first guide shaft and rotating around the second guide shaft. Between the optical axis and one side part of the casing, and between the one diaphragm blade and the optical axis and the other side part of the casing, which are movable between the optical axis and the side of the optical axis. The iris diaphragm mechanism can be inserted into an iris diaphragm mechanism having a pair of diaphragm blades made of the other diaphragm blade that can be moved in the direction of contact with and away from the optical axis and a diaphragm motor that moves the pair of diaphragm blades. A step of inserting between the first and second movable lens groups through the first or second opening portion, and a rotation operation by the first motor to move the first movable lens group in the optical axis direction. The first screw shaft to be operated is One side portion of the housing is closed by a first motor board that is installed in a position parallel to the guide shaft of the first guide shaft and closer to the first guide shaft than the second guide shaft and supports the first motor. And a second screw shaft that is rotated by a second motor and moves the second movable lens group in the optical axis direction in parallel with the second guide shaft and the first screw shaft. And a step of closing the other side of the housing by a second motor substrate that is disposed at a position opposite to each movable lens group and supports the second motor, and the iris diaphragm mechanism is wherein in the first and second step to be inserted between the movable lens group, the first, or, to avoid the second guide shaft, the該虹saturation throttle mechanism after insertion halfway in the housing, wherein Guy provided in the housing The first by inducing in the direction perpendicular to該虹saturation throttle mechanism by de section in the insertion direction, or, while closer to the second guide shaft side, more possible further inserted該虹saturation throttle mechanism, the iris diaphragm The mechanism is disposed on the optical axis, and the diaphragm motor is separated from the first or second guide shaft at one side of the casing or the other side of the casing. it is characterized in that to be placed into the predetermined position offset in the direction.

  In the imaging lens according to the present invention, by having the configuration 1, the first and second guide shafts are arranged at positions opposite to each other of the movable lens groups, and the first movable lens group is The second guide shaft is supported by the first guide shaft so as to be movable in the optical axis direction, and is prevented from rotating around the first guide shaft by the second guide shaft. The shaft is supported by the shaft so as to be movable in the optical axis direction, and the first guide shaft is prevented from rotating around the second guide shaft. The first and second screw shafts are respectively movable lens groups. And the first screw shaft is disposed closer to the first guide shaft than the second guide shaft, Of the screw shaft is located closer to the second guide shaft than the first guide shaft.

  Therefore, in this imaging lens, both the first and second movable lens groups are moved and operated while both sides are guided by the first and second guide shafts, and the first screw shaft is the first one. Since the second screw shaft is close to the second guide shaft, it can be moved stably and smoothly.

  In this imaging lens, since the first screw shaft is close to the first guide shaft and the second screw shaft is close to the second guide shaft, the housing can be thinned.

The housing, the other side including the region one side portion and the second guide shaft and a second screw shaft including a region where the first guide shaft and the first screw shaft is disposed is located The first opening portion and the second opening portion are respectively formed, and the first and second opening portions support the first motor board and the second motor that support the first motor. Since each lid is closed by the second motor board, the number of parts is small and reliable light shielding can be performed.

  Further, in the imaging lens according to the present invention, by having the configuration 2, the aperture motor is located on one side of the casing or the other side of the casing, and the first guide shaft or Since it is biased away from the second guide shaft, it is possible to reduce the thickness of the housing while avoiding interference with the guide shaft.

In the method for manufacturing an imaging lens according to the present invention, having the configuration 3, in the step of inserting the iris diaphragm mechanism between the first and second movable lens groups , the iris diaphragm mechanism is In the step of inserting between the first and second movable lens groups, the iris diaphragm mechanism is inserted halfway into the casing, avoiding the first or second guide shaft, and then the casing. The iris diaphragm mechanism is further inserted while being moved toward the first or second guide shaft by guiding the iris diaphragm mechanism in a direction orthogonal to the insertion direction by a guide portion provided in the body. Accordingly , the iris diaphragm mechanism is disposed on the optical axis, and the diaphragm motor is disposed on one side of the casing or on the other side of the casing. Ga Than the Ru is disposed to a predetermined position offset in spaced direction from Doshafuto, it is thinner casing, avoiding interference with the iris diaphragm mechanism and the guide shaft, and can facilitate the production .

  That is, the present invention provides a guide shaft that movably supports each movable lens group in an imaging lens having at least a first and a second movable lens group and an iris diaphragm mechanism disposed between these movable lens groups. By appropriately setting the positional relationship between the iris diaphragm and the movable range of the iris blades of the iris diaphragm mechanism, the size and thickness of the iris can be reduced, and each movable lens group is stably supported by the guide shaft and smoothly moved. Therefore, it is possible to provide an imaging lens in which the optical axis is prevented from being tilted or vibrated due to the movement operation of each movable lens group.

  In addition, the present invention can provide an imaging lens manufacturing method for easily manufacturing such an imaging lens.

[Embodiment of imaging lens]
Hereinafter, the best mode of an imaging lens according to the present invention will be described in detail.

  FIG. 1 is an exploded perspective view showing a configuration of an imaging lens according to the present invention.

  FIG. 2 is a longitudinal sectional view showing the configuration of the imaging lens according to the present invention.

  As shown in FIGS. 1 and 2, the imaging lens according to the present invention includes at least first and second movable lens groups 1 and 2 and an iris diaphragm disposed between these movable lens groups 1 and 2. An imaging lens having a mechanism 3 and arranged on the optical axis.

  Each of the first and second movable lens groups 1 and 2 includes a plurality of lenses, and these lenses are configured to be supported by a lens frame. Each of the first and second movable lens groups 1 and 2 has a function of performing focus adjustment (focusing) and focal length adjustment (zooming) by moving in the optical axis direction.

  The iris diaphragm mechanism 3 faces one diaphragm blade 4 that is movable in the contact / separation direction with respect to the optical axis, and faces the one diaphragm blade 4 via the optical axis, and is movable in the contact / separation direction with respect to the optical axis. It has a pair of diaphragm blades made up of the other diaphragm blade 5 made. These diaphragm blades 4 and 5 are housed in a thin case 6 and are movable. The iris diaphragm mechanism 3 includes a diaphragm motor 7 that moves the pair of diaphragm blades 4 and 5. The pair of aperture blades 4 and 5 are moved and operated in the case 6 by the aperture motor 7, and adjust the aperture diameter of the through hole formed between them to adjust the aperture ratio of the imaging lens. .

  The first and second movable lens groups 1 and 2 and the iris diaphragm mechanism 3 are housed in a housing 8. The housing 8 is formed in a substantially rectangular shape, and one side (the upper surface in FIGS. 1 and 2) and the other side (the lower surface in FIGS. 1 and 2) are open. The casing 8 is formed of a synthetic resin material or the like by injection molding, and is formed with high shape accuracy according to the accuracy of the mold. The inner surface of the housing 8 is preferably subjected to antireflection treatment such as black coating or embossing in order to prevent irregular reflection of light.

  Further, a front group (front lens) 9 is fixed and attached to the front surface portion of the housing 8, and an opening 10 through which a light beam passing through the front group 9 passes is formed. The front group 9 is a lens group closest to the subject among the lens groups constituting the imaging lens.

  An opening 11 is formed on the rear surface of the housing 8, and an image sensor 12 that captures the light beam that has passed through the opening 11 is attached. Further, a partition wall portion 13 is provided in the housing 8 so as to be positioned in the vicinity of the iris diaphragm mechanism 3 and to divide the housing 8 into the front and rear. An opening is formed in the partition wall 13, and an intermediate group 14 through which a light beam passing through the opening is transmitted is attached. The intermediate group 14 is a lens group located between the movable lens groups 1 and 2.

  A first guide shaft 15 that supports the first movable lens group 1 is installed parallel to the optical axis and attached to one side (upper surface in FIGS. 1 and 2) of the housing 8. Yes. The lens frame of the first lens group 1 is provided with a support ring portion 16 through which the first guide shaft 15 is inserted. The first lens group 1 is supported so as to be movable in the axial direction of the first guide shaft 15 by inserting the first guide shaft 15 through the support ring portion 16. The first guide shaft 15 is positioned and disposed in the housing 8 with both ends fixed. At this time, since the housing 8 has high shape accuracy, the position of the first guide shaft 15 is also positioned with high accuracy.

  The first movable lens group 1 is housed in the housing 8 on the front side (subject side) of the iris diaphragm mechanism 3 while being supported by the first guide shaft 15.

  A second guide shaft 17 that supports the second movable lens group 2 is installed parallel to the optical axis and attached to the other side (the lower surface in FIGS. 1 and 2) of the housing 8. It has been. The lens frame of the second lens group 2 is provided with a support ring portion 18 through which the second guide shaft 17 is inserted. The second lens group 2 is supported so as to be movable in the axial direction of the second guide shaft 17 by inserting the second guide shaft 17 through the support ring portion 18. The second guide shaft 17 is positioned and disposed in the housing 8 with both ends fixed. At this time, since the housing 8 has high shape accuracy, the position of the second guide shaft 17 is also positioned with high accuracy.

  The second movable lens group 2 is housed in the housing 8 on the rear side (image sensor side) of the iris diaphragm mechanism 3 while being supported by the second guide shaft 17.

  In this imaging lens, the first and second guide shafts 15 and 17 are arranged at positions opposite to each other of the movable lens groups 1 and 2. The first movable lens group 1 is supported by the first guide shaft 15 so as to be movable in the optical axis direction, and the second guide shaft 17 prevents rotation around the first guide shaft 15. Has been. That is, the lens frame of the first movable lens group 1 is provided with a hook 19 that is positioned on the opposite side of the support ring portion 16 and engages with the second guide shaft 17.

  The second movable lens group 2 is supported by the second guide shaft 17 so as to be movable in the optical axis direction, and the first guide shaft 15 prevents rotation around the second guide shaft 17. Has been. The lens frame of the second movable lens group 2 is provided with a hook 20 that is positioned on the opposite side of the support ring 18 and that engages with the first guide shaft 15.

  In this imaging lens, since the guide shafts 15 and 17 are disposed on the opposite sides via the movable lens groups 1 and 2, the movable lens groups 1 and 2 are affected by gravity. It is supported stably.

  A first screw shaft that is installed in parallel with the first guide shaft 15 and is rotated by the first motor 21 on one side (the upper surface in FIGS. 1 and 2) in the housing 8. 22 is provided. A clamper 23 for transmitting the driving force of the first motor 21 is disposed in the lens frame of the first movable lens group 1. The first movable lens group 1 is operated to move in the optical axis direction by transmitting the driving force of the first motor 21 via the first screw shaft 22 and the clamper 23.

  Further, on the other side (the lower surface in FIGS. 1 and 2) in the housing 8, a second screw shaft that is installed in parallel with the second guide shaft 17 and is rotated by the second motor 24. 25 is provided. A clamper 26 for transmitting the driving force of the second motor 24 is disposed in the lens frame of the second movable lens group 2. The second movable lens group 2 is driven to move in the optical axis direction by transmitting the driving force of the second motor 24 via the second screw shaft 25 and the clamper 26.

  The first and second screw shafts 22 and 25 do not need to be provided over the movable range of the first and second movable lens groups 1 and 2, respectively. It is only necessary that the second screw shaft 25 is provided over the movable range of the second movable lens group 2.

  The first and second screw shafts 22 and 25 are arranged at positions opposite to each other via the optical axes of the movable lens groups 1 and 2. The first screw shaft 22 is disposed at a position closer to the first guide shaft 15 than the second guide shaft 17, and the second screw shaft 25 is more than the first guide shaft 15. 2 near the guide shaft 17. That is, in the housing 8, the region where the first guide shaft 15 and the first screw shaft 22 are arranged corresponds to one open side (upper surface in FIGS. 1 and 2). In the housing 8, the region where the second guide shaft 17 and the second screw shaft 25 are disposed corresponds to the opened other side portion (the lower surface portion in FIGS. 1 and 2).

  By the way, in the iris diaphragm mechanism 3, one diaphragm blade 4 moves in the contact / separation direction with respect to the optical axis between the optical axis and one side of the casing 8 (upper surface in FIGS. 1 and 2). It is possible. The other diaphragm blade 5 is movable between the optical axis and the other side portion of the housing 8 (the lower surface portion in FIGS. 1 and 2) in the contact / separation direction with respect to the optical axis. Therefore, the iris diaphragm mechanism 3 is configured in a rectangular shape in which the direction from one side of the housing 8 to the other side is the long side direction according to the cross-sectional shape of the housing 8. In the iris diaphragm mechanism 3, the diaphragm motor 7 is located on the other side (or one side) of the housing 8 and is separated from the second guide shaft 17 (or the first guide shaft 15). It is arranged in a biased direction.

  The one side and the other side (the upper surface and the lower surface in FIGS. 1 and 2) of the housing 8 are opened to the first motor board 27 and the second motor substrate 27 that support the first motor 21. Each lid is closed by a second motor substrate 28 that supports the motor 24. These first and second motor boards 27 and 28 are attached to the housing 8 by, for example, screwing.

  Further, the first and second motor substrates 27 and 28 are not limited to those made of a synthetic resin material, and metals, for example, those formed by processing a sheet metal can be used.

  A light shielding wall 29 may be provided on the inner side of the opened one side and the other side of the housing 8 in a range that does not hinder the moving operation of the movable lens groups 1 and 2. In addition, the surface portions of the first and second motor boards 27 and 28 facing inward of the housing 8 and the outer surface portions of the first and second motors 21 and 24 are black in order to prevent irregular reflection of light. It is desirable to apply an antireflection treatment such as painting or embossing.

  In the imaging lens according to the present invention configured as described above, the first and second movable lens groups 1 and 2 are both movable, particularly, movable by the first and second guide shafts 15 and 17. Since the first screw shaft 22 is close to the first guide shaft 15 and the second screw shaft 25 is close to the second guide shaft 17, the lens groups 1 and 2 are guided on the opposite side. And moving smoothly. In this imaging lens, the first screw shaft 22 is close to the first guide shaft 15, and the second screw shaft 25 is close to the second guide shaft 17, so that the housing 8 can be thinned. It becomes.

  Furthermore, in this imaging lens, since the aperture motor 7 is arranged so as to be biased away from the second guide shaft 17 (or the first guide shaft 15), the iris diaphragm mechanism 3 and the guide shaft 15 are arranged. , 17 is avoided, and the casing 8 can be made thinner.

  By making the moving direction of the diaphragm blades 4 and 5 in the iris diaphragm mechanism 3 the vertical direction on the imaging screen, the through hole formed between the diaphragm blades 4 and 5 becomes a horizontally long opening. It is possible to prevent the difference in illuminance in the left-right direction within the angle of view, and to prevent deterioration in horizontal resolution.

[Embodiment of Manufacturing Method of Imaging Lens]
The best mode for manufacturing an imaging lens according to the present invention will be described below.

  In order to manufacture the imaging lens according to the present invention as described above, the housing 8 is first manufactured. The casing 8 is made of synthetic resin by injection molding into a substantially rectangular shape with one side (upper surface in FIGS. 1 and 2) and the other side (lower surface in FIGS. 1 and 2) opened. It is made of material. The casing 8 can be formed with high shape accuracy according to the accuracy of the mold. The inner surface of the housing 8 is preferably subjected to an antireflection treatment such as black coating or embossing in order to prevent irregular reflection of light.

  Next, the front group (front ball) 9 and the intermediate group 14 are attached to the housing 8. The front group 9 is fixed by an adhesive or heat caulking in accordance with the opening 10 formed in the front portion of the housing 8. The intermediate group 14 is fixed by an adhesive or heat caulking in accordance with the opening formed in the partition wall 13 of the housing 8.

  Then, the image pickup device 12 is attached to the housing 8 in accordance with the opening 11 in the rear surface portion of the housing 8. In addition, you may perform attachment of the image pick-up element 12 after manufacture of an imaging lens is completed.

  Next, the first guide shaft 15 that supports the first movable lens group 1 in the support ring 16 is attached to the opened one side portion of the housing 8, and the first movable lens group 1 is attached to the housing 8. While being inserted into the body 8, the first guide shaft 15 is installed parallel to the optical axis. At this time, the first guide shaft 15 is positioned and disposed in the housing 8 with both ends fixed.

  Next, the second guide shaft 17 that supports the second movable lens group 2 at the support ring portion 18 is attached to the other side portion of the housing 8 that is open, and the second movable lens group 2 is attached to the housing. While being inserted into the body 8, the second guide shaft 17 is installed parallel to the optical axis. At this time, the second guide shaft 17 is positioned and disposed in the housing 8 with both ends fixed. At this time, the second guide shaft 17 is disposed at a position opposite to the movable lens groups 1 and 2 with respect to the first guide shaft 15.

  Then, the engagement rod 19 of the first movable lens group 1 is engaged with the second guide shaft 17 so that the first movable lens group 1 does not rotate around the first guide shaft 15. Further, the engaging rod 20 of the second movable lens group 2 is engaged with the first guide shaft 15 so that the second movable lens group 2 does not rotate around the second guide shaft 17.

  Next, the iris diaphragm mechanism 3 is inserted between the first and second movable lens groups 1 and 2 from one side or the other side of the housing 8.

  FIG. 3 is a longitudinal sectional view showing a process of inserting an iris diaphragm mechanism in the method of manufacturing an imaging lens according to the present invention.

  At this time, as shown in FIGS. 3A to 3C, the iris diaphragm mechanism 3 avoids the second guide shaft 17 and goes halfway from the other side of the housing 8 into the housing 8. After the insertion, as shown in (d) to (e) of FIG. 3, the iris diaphragm mechanism 3 is disposed on the optical axis by being further inserted while being moved toward the second guide shaft 17 side. Like that. Then, the iris diaphragm mechanism 3 is fixed to the housing 8. At this time, the aperture motor 7 is disposed at a position biased in the direction away from the second guide shaft 17 on the other side of the housing 8.

  Note that the iris diaphragm mechanism 3 may be inserted from one side of the housing 8. In this case, the iris diaphragm mechanism 3 avoids the first guide shaft 15 and enters the housing 8 halfway. Then, the iris diaphragm mechanism 3 is arranged on the optical axis by further inserting it while moving it toward the first guide shaft 15 side.

Here, a guide wall 30 is provided in the housing 8 as a guide portion for guiding the iris diaphragm mechanism 3 inserted halfway into the housing 8 in the direction toward the second guide shaft 17. It is desirable to keep it. The guide wall 30 has a side surface inclined with respect to the insertion direction of the iris diaphragm mechanism 3, and the distal end side of the case 6 of the iris diaphragm mechanism 3 as the iris diaphragm mechanism 3 is inserted. The iris diaphragm mechanism 3 is guided and moved in a direction orthogonal to the insertion direction when the side edge portions of the first and second sides abut.

  By providing such a guide wall 30, the moving direction of the iris diaphragm mechanism 3 is guided and inserted into the housing 8 halfway by simply inserting the iris diaphragm mechanism 3 in one direction. The iris diaphragm mechanism 3 is moved toward the second guide shaft 17 and reaches a predetermined position.

  The first screw shaft 22 that is rotated by the first motor 21 is parallel to the first guide shaft 15 and closer to the first guide shaft 15 than the second guide shaft 17. The opened one side portion of the housing 8 is closed by the first motor substrate 27 that is attached and supports the first motor 21.

  In addition, the second screw shaft 25 that is rotated by the second motor 24 is parallel to the second guide shaft 17 and closer to the second guide shaft 17 than the first guide shaft 15. The second side of the housing 8 is closed by the second motor board 28 that is attached and supports the second motor 24.

  In this way, the first and second motor boards 27 and 28 are attached to the housing 8 to complete the imaging lens.

  In this imaging lens manufacturing method, any one of the first guide shaft 15 supporting the first movable lens group 1 and the second guide shaft 17 supporting the second movable lens group 2 is used. May be inserted into the housing 8 and fixed from the opened side of the housing 8 or from the other side, that is, from the same direction. In this case, the second guide shaft 17 inserted from one open side of the housing 8 can reach the other side, or from the other open side of the housing 8. A guide groove may be formed in the housing 8 so that the inserted first guide shaft 15 can reach one side.

It is a disassembled perspective view which shows the structure of the imaging lens which concerns on this invention. It is a longitudinal cross-sectional view which shows the structure of the imaging lens which concerns on this invention. It is a longitudinal cross-sectional view which shows the process of inserting an iris diaphragm mechanism in the manufacturing method of the imaging lens which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st movable lens group 2 2nd movable lens group 3 Iris diaphragm mechanism 4 One diaphragm blade 5 Other diaphragm blade 7 Diaphragm motor 8 Housing | casing 15 1st guide shaft 17 2nd guide shaft 21 1st Motor 22 First screw shaft 24 Second motor 25 Second screw shaft 27 First motor board 28 Second motor board

Claims (3)

An imaging device comprising at least a first and a second movable lens group and an iris diaphragm mechanism disposed at a predetermined position between each of the movable lens groups, which are arranged on the optical axis. A lens,
A housing that houses the first and second movable lens groups and the iris diaphragm mechanism;
A first guide shaft attached to the housing and installed parallel to the optical axis and supporting the first movable lens group;
A first screw shaft that is installed in parallel to the first guide shaft and is rotated by a first motor to move the first movable lens group in the optical axis direction;
A second guide shaft attached to the housing and installed in parallel to the optical axis and supporting the second movable lens group;
A second screw shaft installed in parallel to the second guide shaft and rotated by a second motor to move and move the second movable lens group in the optical axis direction;
The first and second guide shafts are arranged at positions opposite to each other of the movable lens groups,
The first movable lens group is supported by the first guide shaft so as to be movable in the optical axis direction, and is prevented from rotating around the first guide shaft by the second guide shaft.
The second movable lens group is supported by the second guide shaft so as to be movable in the optical axis direction, and the first guide shaft is prevented from rotating around the second guide shaft,
The first and second screw shafts are arranged at positions opposite to each other of the movable lens groups, and the first screw shaft is located on the first guide shaft rather than the second guide shaft. Arranged near the second screw shaft, closer to the second guide shaft than the first guide shaft,
The housing includes one side including a region where the first guide shaft and the first screw shaft are disposed, and a region where the second guide shaft and the second screw shaft are disposed. A first opening part and a second opening part are formed on the side parts, respectively.
In the first or second opening, the iris diaphragm mechanism can be inserted,
Wherein the housing, in the course of the iris diaphragm mechanism is inserted into between the first or the second opening portion of the groups each of the movable lens, 該虹saturation throttle mechanism the first, or second The iris diaphragm mechanism is inserted halfway into the housing while avoiding the guide shaft, and then moved toward the first or second guide shaft side when the iris diaphragm mechanism is further inserted. insertion by guiding in the direction perpendicular to the direction, the guide portion is provided該虹saturation throttle mechanism is by cormorants induction are disposed in the predetermined position,
The first and second opening portions are respectively closed by a first motor board that supports the first motor and a second motor board that supports the second motor. Imaging lens. The iris diaphragm mechanism includes one diaphragm blade that is movable between the optical axis and one side portion of the casing in a contact / separation direction with respect to the optical axis, and the optical axis and the other side section of the casing. A pair of diaphragm blades made of the other diaphragm blades that are movable in the direction of contact with and away from the optical axis, and a diaphragm motor that moves the pair of diaphragm blades.
The aperture motor is located on one side of the casing or the other side of the casing, and is biased in a direction away from the first guide shaft or the second guide shaft. The imaging lens according to claim 1, wherein: Manufacture of an imaging lens that manufactures an imaging lens by disposing at least the first and second movable lens groups and an iris diaphragm mechanism disposed at a predetermined position between these movable lens groups on the optical axis. A method,
A first guide shaft that supports the first movable lens group with respect to a first opening portion on one side of a housing that houses the first and second movable lens groups and the iris diaphragm mechanism. Attaching, inserting the first movable lens group into the housing, and installing the first guide shaft parallel to the optical axis;
A second guide shaft that supports the second movable lens group is attached to a second open portion on the other side of the casing, and the second movable lens group is inserted into the casing. And disposing the second guide shaft in a position parallel to the optical axis and on the opposite side of each movable lens group with respect to the first guide shaft;
Engaging the first movable lens group with the second guide shaft and preventing rotation about the first guide shaft;
Engaging the second movable lens group with the first guide shaft to prevent rotation around the second guide shaft;
One diaphragm blade that is movable between the optical axis and one side part of the casing in the direction of contact with the optical axis, and the light between the optical axis and the other side part of the casing. The iris diaphragm mechanism can be inserted into an iris diaphragm mechanism having a pair of diaphragm blades made of the other diaphragm blade that is movable in the direction of contact with and away from the shaft and a diaphragm motor that moves the pair of diaphragm blades. Inserting between the first and second movable lens groups from the first or second opening portion,
A first screw shaft that is rotated by a first motor to move the first movable lens group in the optical axis direction is parallel to the first guide shaft and from the second guide shaft. A step of closing the one side of the housing by a first motor board that is installed at a position close to the first guide shaft and supports the first motor;
A second screw shaft that is rotated by a second motor and operates to move the second movable lens group in the optical axis direction is parallel to the second guide shaft and is connected to the first screw shaft. And a step of closing the other side portion of the housing by a second motor substrate that is disposed at a position opposite to each of the movable lens groups and supports the second motor, and
In the step of inserting the iris diaphragm mechanism between the first and second movable lens groups, avoiding the first or second guide shaft, the iris diaphragm mechanism is partway in the casing. after insertion, the said by induction in a direction perpendicular to該虹saturation throttle mechanism in the insertion direction by the guide portion provided in the housing first, or, while closer to the second guide shaft side, 該虹saturation throttle mechanism more to the further insertion, with disposing the iris diaphragm mechanism on the optical axis, the iris motor, one side of the housing or, in the other side of said housing, said first Alternatively, the imaging lens manufacturing method is characterized in that the imaging lens is arranged at the predetermined position biased in a direction away from the second guide shaft.

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