JP2016031443A - Lens barrel and optical device having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens barrel capable of having no loss of images when a filter is replaced and being reduced in size, and an optical device.SOLUTION: A lens barrel includes insertion/removal means for inserting or removing an IR cut filter 161, on an optical path. The insertion/removal means has a holder 160 for holding the IR cut filter 161. The holder 160 is composed of the combination of division holders 164, 167. The division holders 164, 167 are provided with a groove 165 into which the IR cut filter 161 is inserted by sliding.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a lens barrel and an optical apparatus.

  In recent years, optical devices such as video cameras include a variety of media such as tapes, built-in disks, and the like as recording media, and those that can be remotely operated via a network. As described above, when developing and manufacturing various types of camera devices, the use of as many common parts as possible can improve the efficiency of development and manufacturing.

  Further, in a conventional optical device such as a video camera, a mechanism for arbitrarily inserting and removing an optical element is provided. For example, the surveillance camera is provided with an IR cut filter having an optical characteristic for cutting infrared rays immediately before the image sensor. The reason why this IR cut filter is used is to avoid the reproducible camera image becoming cloudy and the color reproducibility being deteriorated when the incident light to the image sensor includes infrared rays. Therefore, an IR cut filter is permanently installed on the optical path of a normal color dedicated camera in order to cut near-infrared and infrared light that adversely affects photographing and obtain a suitable image.

  On the other hand, in recent years, the demand for surveillance cameras has increased, and many cameras are equipped with a night mode that can be photographed even under low illumination such as at night. Generally, the IR cut filter is removed from the optical path in order to obtain a larger amount of light during night photography.

  On the other hand, in a bright environment such as daytime, such a camera device is generally capable of disposing an IR cut filter on the optical path in order to obtain an image with good color reproducibility, like a color dedicated camera. Is. Therefore, such a camera device is provided with an IR cut filter switching mechanism that inserts and retracts the IR cut filter on the optical path before the image sensor.

  In general, an optical filter such as an IR cut filter is formed of an optical member such as glass. Therefore, when the optical filter is simply inserted and removed, the optical refractive index of air differs from that of the optical filter. The position will change.

  Patent Document 1 discloses an optical device that can hold an optical filter and a dummy glass independently. In this optical apparatus, when the IR cut filter is removed from the optical system, a dummy glass is inserted instead of the IR cut filter so that the focal position does not change.

JP 2010-008801 A

  However, in the technique disclosed in Patent Document 1, for example, since the support beam is bridged between the optical filter and the dummy glass, the shadow of the support beam is reflected when switching from the optical filter to the dummy glass, and the image Could be lost. In addition, since a support beam must be disposed between the optical filter and the dummy glass, the space between the optical filter and the dummy glass cannot be reduced, and it is difficult to reduce the size of the lens barrel and the optical device.

  The present invention has been made in view of such a situation. For example, an object of the present invention is to provide a lens barrel and an optical apparatus that can be downsized without loss of an image when a filter is switched.

  In order to solve the above problems, the present invention provides a lens barrel having an insertion / removal unit for inserting / removing at least one optical element on an optical path, wherein the insertion / removal unit has a holder for holding the optical element. The holder is formed by combining a plurality of split holders, and the split holder is provided with a groove for slidingly inserting the optical element.

  According to the present invention, for example, since the optical element is slid and held in the groove, there is no support member on at least one side of the optical element. Possible lens barrels and optical instruments can be provided.

It is a disassembled perspective view of the optical apparatus which concerns on 1st Embodiment. It is a disassembled perspective view of the optical filter apparatus of 1st Embodiment. It is a perspective view of an optical filter apparatus. It is a disassembled perspective view of the optical filter apparatus of 2nd Embodiment. It is a perspective view of an optical filter apparatus. It is a figure which shows an optical apparatus provided with an optical filter apparatus. It is a perspective view which shows an optical apparatus provided with an optical filter apparatus. It is a figure which shows IR meter. It is the figure which looked at the optical filter device from the image sensor side. It is the figure which looked at the optical filter device from the image sensor side. It is the figure which looked at the optical filter apparatus from the object side. It is sectional drawing of an optical filter apparatus and an optical apparatus. It is the figure which looked at the optical filter apparatus from the object side. It is the figure which looked at the optical filter apparatus from the object side.

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

  First, the lens barrel according to the first embodiment of the present invention will be described. FIG. 1 is an exploded perspective view of a lens barrel 100 according to the present embodiment. As an example, the lens barrel 100 is applied to an imaging device such as a digital still camera, a video camera, and a television camera, and an optical device such as an interchangeable lens device, binoculars, a telescope, and a field scope. In addition, the lens barrel 100 may be built in the imaging apparatus, and is not limited to the imaging apparatus. For example, the lens barrel 100 is built into an interchangeable lens that can be attached to and detached from a projection apparatus such as a so-called projector, or a projection apparatus. May be. In addition, the lens barrel 100 may have a moving mechanism that allows the lens to move in the optical axis direction in relation to the zoom function or the focus function.

  The lens barrel 100 has a variable magnification optical system (imaging optical system) configured by four lens units L1 to L4. L1 is a fixed first lens unit, and L3 is a fixed third lens unit. L2 is a second lens unit that moves in the optical axis direction and performs zooming. L4 is a fourth lens unit that performs a focusing operation that moves in the optical axis direction, corrects image plane fluctuations accompanying zooming, and performs focus adjustment. AXL shown in FIG. 1 indicates the optical axis of the photographing optical system.

  The lens holding frame 1 holds the first lens unit L1. The second moving frame 2 holds the second lens unit L2. The holding frame 3 holds the third lens unit L3. The fourth group moving frame 4 holds the fourth lens unit L4. The aperture unit 5 adjusts the amount of light passing through the photographing optical system, and moves the aperture blades in opposite directions to change the aperture diameter. The diaphragm actuator 6 is, for example, a stepping motor that moves the diaphragm blades.

  The image sensor fixing holder 400 fixes an image sensor such as a CCD sensor or a CMOS sensor. The front fixed barrel 11 and the rear fixed barrel 200 are combined with each other and integrated by screwing to constitute a fixed barrel for fixing each component. The guide bars 7 and 9 extend in the optical axis direction, and both ends thereof are held by the front fixed barrel 11 and the rear fixed barrel 200. The guide bar 8 extends in the optical axis direction, and both ends thereof are held by the front fixed barrel 11 and the lens holding frame 3. The guide bar 10 extends in the optical axis direction, and both ends thereof are held by the lens holding frame 3 and the rear fixed barrel 200. The guide bars 7 and 8 guide the movement of the second moving frame in the optical axis direction, and the guide bars 9 and 10 guide the movement of the fourth moving frame in the optical axis direction.

  The zoom motor 12 is a motor that moves the second moving frame 2 in the optical axis direction, and a stepping motor is used. The zoom motor 12 has a lead screw that is invisible in the figure and rotates with the rotor. A rack attached to the second moving frame 2 meshes with the lead screw, and the second moving frame 2 moves in the optical axis direction by the rotation of the rotor and the lead screw. The zoom motor 12 is fixed to the rear fixed barrel 200 with screws.

  The focus motor 13 is a motor that moves the fourth moving frame 4 in the optical axis direction, and a stepping motor is used. The focus motor 13 has a lead screw that is invisible in the drawing and rotates together with the rotor. A rack attached to the fourth moving frame 4 is engaged with the lead screw, and the fourth moving frame 4 moves in the optical axis direction by the rotation of the rotor and the lead screw. The focus motor 13 is fixed to the rear fixed barrel 200 with screws.

  The IR holder 160 (or 180) is detachably attached to the image sensor fixing holder 400, and holds an optical filter such as an IR cut filter 161 (FIG. 2). The IR holder 160 (or 180) is integrally engaged with an IR meter 300 which is a drive unit for switching the optical filter. According to FIG. 1, the fourth moving frame 4 can move to a position before colliding with the IR cut filter 161 and the IR holder 160 within a tolerance range.

  2 and 3 are detailed views of the IR holder 160 holding the IR cut filter and the dummy glass in the lens barrel according to the present embodiment.

  2 and 3, AXL indicates the optical axis direction of the optical device when used as an optical device. FIG. 2 is an exploded perspective view of the IR holder 160 before assembly. The IR holder 160 is divided into two parts and is configured by combining a plurality of divided holders. That is, the IR holder 160 includes a split holder 164 that holds the IR cut filter 161 and a split holder 167 that holds the dummy glass 162.

  The split holder 164 has a groove 165 into which the IR cut filter 161 is inserted. The split holder 164 has a U-shape in a plane orthogonal to the optical axis AXL, and grooves 165 are provided on the inner sides of three sides constituting the U-shape portion.

  The split holder 167 has a groove 168 into which the dummy glass 162 is slid and inserted. The split holder 167 has a U-shape in a plane orthogonal to the optical axis AXL, and a groove 168 is provided on the inner side of three sides constituting the U-shape portion.

  The division holders 164 and 167 have fin portions 166 and 169 for forming adhesion holes (adhesion portions) for bonding the two division holders together as one body. The fins 166 and 169 protrude in the horizontal direction, that is, along a plane orthogonal to the optical axis AXL, at both ends of the U-shaped portions of the divided holders 164 and 167. When the fin portions 166 and 169 of the split holders 164 and 167 are combined, one is arranged on the upper side and the other is arranged on the lower side, that is, arranged so as to be staggered.

  Of the three sides constituting the U-shaped portion of the split holder 164, a semicircular cutout 174 is provided inside the central side facing the split holder 167. An engagement hole 170 for engaging with the IR meter 300 as a drive unit is provided at the end of the split holder 164 and at the end opposite to the split holder 167. A rib 171 that engages with the guide groove of the lens barrel when the IR holder 160 is driven in the lens barrel is provided at the end of the split holder 167 opposite to the split holder 164. Yes. The split holders 164 and 167 are provided with three IR holder sliding portions 172 for restricting the tilt in the optical axis direction within the lens barrel. The IR holder sliding portion 172 is provided so as to protrude from the side surfaces of the split holders 164 and 167 along a plane orthogonal to the optical axis AXL. The IR holder sliding portion 172 forms a substantially triangular shape when viewed from the optical axis direction.

  FIG. 3 is a perspective view showing a state in which the two divided holders 164 and 167 described in FIG. 2 are assembled. The assembly of the IR holder 160 is performed as follows. An IR cut filter 161 as an optical element is slid and inserted into a groove 165 provided in the division holder 164. The optical element may have other optical characteristics in addition to an IR cut filter having an optical characteristic for cutting infrared rays. Further, the dummy glass 162 is slid and inserted into the groove 168 provided in the split holder 167. The split holder 164 in which the IR cut filter 161 is inserted and the split holder 167 in which the dummy glass 162 is inserted are combined with the fin portions 166 and 169 different from each other. At this time, the fin portion 166 of the split holder 164 and the split holder 167 are in contact with each other, and the fin portion 169 of the split holder 167 and the split holder 164 are in contact with each other. Further, one side of the IR cut filter 161 is in contact with one side of the dummy glass 162. As described above, it is desirable that these three locations are in contact, but any one of the three locations may be in contact, and the other contact locations may have a slight gap.

  By combining the split holder 164 and the fins 166, 169 of the split holder 167, two holes of an invisible adhesive hole 179 in the figure are formed on the opposite side of the adhesive hole 178 and the adhesive hole 178. When looking through the adhesive hole 178 and the adhesive hole 179, only the side surface of the IR cut filter 161 can be seen from the direction orthogonal to the optical axis. The end face of the IR cut filter 161 is exposed from the notch 174 of the split holder 164 that holds the IR cut filter. In this state, the IR cut filter 161 and the dummy glass 162 may have a slight backlash in the sliding direction along the grooves 165 and 168 with respect to the IR holder 160.

  The split holders 164 and 167 and the IR cut filter 161 are bonded together by putting an adhesive into the bonding hole 178 and the bonding hole 179 on the opposite side and curing it. At this time, the IR cut filter 161 is bonded to the dummy glass 162 in the direction I from the notch 174 of the split holder 164. As a result, the IR cut filter 161 and the dummy glass 162 are bonded in a state where slight backlash in the sliding direction is reduced.

  The IR cut filter 161 and the dummy glass 162 are slid and inserted into the grooves 165 and 168, respectively. That is, the split holders 164 and 167 are open at least one side of the portion holding the IR cut filter 161 and the dummy glass 162, and no support member is provided here.

  Thus, the IR holder 160 after bonding is integrated, and in the integrated state, the play of the IR cut filter 161 with respect to the IR holder 160 is eliminated. The dummy glass 162 that is not bonded alone is fixed at three sides by a groove 168 provided in the divided holder 167, and the remaining one side is in contact with the IR cut filter 161 whose position is fixed by bonding. Fixed. In addition, when the notch 174 is adhered, it is possible to further strengthen the adhesion between the IR cut filter 161 and the divided holder 164.

  As described above, in the IR holder 160, since there is no support member between the IR cut filter 161 and the dummy glass 162, no image is lost when the IR cut filter 161 described later is switched. Further, although only the three sides of the IR cut filter 161 are held, the IR cut filter 161 is inserted into the groove 165, so that it has sufficient strength as compared with the case where only the adhesive is held. Can have.

  Next, a lens barrel according to a second embodiment of the present invention will be described. In the first embodiment, the IR holder 160 has the IR cut filter 161 and the dummy glass 162, but in the second embodiment, no dummy glass is provided, and only the IR cut filter 161 is provided. The overall configuration of the lens barrel of the second embodiment is the same as that of the first embodiment shown in FIG.

  4 and 5 are detailed views of the IR holder 180 holding the IR cut filter and the dummy glass in the lens barrel according to the present embodiment.

  4 and 5, AXL indicates the optical axis direction of the optical device when used as an optical device. FIG. 4 is an exploded perspective view of the IR holder 180 before assembly. The IR holder 180 is divided into two parts, and includes a split holder 184 that holds the IR cut filter 181 and a split holder 187 that does not hold the dummy glass. The split holders 184 and 187 have the same shape as the split holders 164 and 167 shown in FIG.

  The dividing holder 184 is provided with a groove 185 into which the IR cut filter 181 is slid and inserted. The split holder 187 has a groove 188 into which the optical filter is slid, and nothing is inserted here. The split holders 184 and 187 respectively have fin portions 186 and 189 for forming bonding holes for bonding the two divided holders as a single body. The fin portions 186 and 189 protrude along a plane orthogonal to the optical axis AXL, one is arranged on the upper side, and the other is arranged on the lower side, that is, arranged alternately.

  A semicircular arc-shaped notch 194 is provided on the inner side of the central side facing the split holder 187 among the three sides constituting the U-shaped portion of the split holder 184. An engagement hole 190 for engaging with the IR meter 300 as a drive unit is provided at the end of the split holder 184 and opposite to the split holder 187. A rib 191 that engages with the guide groove of the lens barrel when the IR holder 180 is driven in the lens barrel is provided at the end of the split holder 187 opposite to the split holder 184. Yes. The split holders 184 and 187 are provided with three IR holder sliding portions 192 for restricting the tilt in the optical axis direction within the lens barrel.

  FIG. 5 is a perspective view showing a state in which the two divided holders 184 and 187 described in FIG. 4 are assembled. The assembly of the IR holder 180 is performed as follows. The IR cut filter 181 is slid and inserted into the groove 185 provided in the split holder 184. Also, nothing is inserted into the groove 188 provided in the split holder 187. The split holder 184 in which the IR cut filter 181 is inserted and the split holder 187 in which the optical filter is not inserted are combined with the fin portions 186 and 189 differently.

  By combining the split holder 184 and the fins 186 and 189 of the split holder 187, two holes of the adhesive hole 198 and the invisible adhesive hole 199 in the figure are formed on the opposite side of the adhesive hole 198. When looking through the adhesive hole 198 and the adhesive hole 199, only the side surface of the IR cut filter 181 can be seen from the direction orthogonal to the optical axis.

  The divided holders 184 and 187 and the IR cut filter 181 are bonded together by putting an adhesive into the bonding hole 198 and the bonding hole 199 on the opposite side and curing it. At this time, the IR cut filter 181 is bonded from the notch 194 of the split holder 184 while being biased in the direction of the split holder 184, that is, the direction J. As a result, the position of the IR cut filter 181 can be determined, and there is no backlash.

  The IR cut filter 181 is slid and inserted into the groove 185. That is, the split holder 184 is open on at least one side of the portion that holds the IR cut filter 181, and no support member is provided here.

  Thus, the IR holder 180 after bonding is integrated, and in the integrated state, the play of the IR cut filter 181 with respect to the IR holder 180 is eliminated. In addition, when the notch 194 is adhered, the adhesion between the IR cut filter 181 and the divided holder 184 can be further strengthened.

  As described above, in the IR holder 180, only three sides of the IR cut filter 181 are supported, and the remaining one side is exposed, and there is no support member. Therefore, when the IR cut filter 161 described later is switched, an image is lost. There is no. Further, although only the three sides of the IR cut filter 181 are held, the IR cut filter 181 is inserted into the groove 185, so that it has a sufficient strength compared to the case where only the adhesive is held. Can have.

  FIG. 6 is a diagram showing a configuration of an insertion / removal means for inserting / removing an optical element on / from the optical path in the lens barrel according to the present invention. FIG. 6 is a view of the IR holder 160, the IR meter 300, and the rear fixed barrel 200 for fixing them as viewed from the image sensor fixing holder 400 toward the object side. AX indicates an optical path range as an optical apparatus. FIG. 7 is a diagram showing details of the IR meter 300. According to FIG. 7, the arm 301 attached to the rotor of the IR meter 300 is magnetically biased to one of the two ends 304 and 305. Specifically, as shown in FIG. 8, either one of the urging forces FD1 and FD2 is always generated by the magnetic circuit, and one of the end portions 304 or 305 is urged by magnetism when not energized.

  In FIG. 8, an engagement hole 170 (FIG. 7) for engaging with the IR meter 300 provided in the IR holder 160 is engaged with an engagement pin 302 provided in the arm 301 of the IR meter 300. The fixing method of the engaging pin 302 part may be press-fitting as an example, but in the present embodiment, it is fixed by adhesion of an adhesive.

  As shown in FIG. 6, the IR meter 300 is fixed to the rear fixed barrel 200 with screws, and the positions of the IR meter 300 and the IR holder 160 engaged with the IR meter 300 are fixed. A sliding portion 172 provided in the IR holder 160 is in contact with a sliding rail 201 provided in the rear fixed barrel 200 in the optical axis direction.

  As shown in FIG. 8, a guide pin 171 provided on the IR holder 160 is inserted so as to engage with a guide rail 202 substantially parallel to the switching direction X of the IR holder provided on the rear fixed barrel 200. . When an energizing terminal 303 (FIG. 7) provided in the IR meter 300 is energized with an invisible flexible cable in the drawing, a driving force is generated in the arm 301 in the F direction in the drawing, and the end 304 moves in the F direction. Driven.

  FIG. 9 shows a state where the coil holder terminal 303 is energized and the IR holder 160 is switched by the driving force generated in the IR meter 300 of FIG. When the IR meter 300 is energized, a rotational driving force is generated in the arm 301, and the driving force is transmitted to the IR holder 160 through the engagement pin 302. At this time, the IR holder 160 is moved in the direction Y perpendicular to the switching direction X in the plane orthogonal to the optical axis by the guide pin 171 (FIG. 7) engaged with the guide rail of the rear fixed barrel 200. Be regulated. On the other hand, since there are few restrictions on the side of the engagement hole 170 (FIG. 7) that engages with the arm, the rotational drive force is substantially followed on the side of the engagement hole 170 of the IR holder 160. The IR holder 160 tries to switch while swinging by this resultant force, and as shown in FIG. 9, the IR cut filter 161 is removed from the optical path range AX, and the dummy glass 162 is inserted.

  Further, as shown in FIG. 10, when the IR meter 300 rotates in the F direction, the arm 301 comes into contact with the end 305 provided in the IR meter 300, and the rotation of the arm 301 is restricted. The end portion 305 is provided so as to be at the same position on an axis Y orthogonal to the switching direction X in a plane orthogonal to the optical axis with respect to the end portion 304. For this reason, when the arm 301 is in the position of the end 305, the IR holder 160 stops at a position substantially parallel to the switching direction X. As the IR holder 160 moves, the IR cut filter 161 is out of the optical path range AX, and the dummy glass 162 is inserted into the optical path range AX.

  At this time, since there is no support member between the IR cut filter 161 and the dummy glass 162, the component does not cross the optical path range AX when the filter is switched, so that there is no loss of image.

  On the contrary, when the dummy glass is removed from the optical path range AX and the IR cut filter 161 is inserted, the IR holder 160 is moved in the order of FIGS. The IR cut filter 161 is inserted.

  FIG. 11 is a diagram showing a configuration of an optical element insertion / removal mechanism in the lens barrel according to the present invention. FIG. 6 is a view of the IR holder 160, the IR meter 300, and the image sensor fixing holder 400 for fixing them as viewed from the image sensor side. The sliding part 172 provided in the IR holder 160 is in contact with the three positions of the sliding rail 401 provided in the imaging element fixing holder 400 in the optical axis direction. FIG. 12 is a cross-sectional view of the IR meter sliding portion, the sliding rail 201 of the rear fixed barrel 200, and the sliding rail 401 of the image sensor fixing holder 400 viewed from a direction orthogonal to the optical axis. The sliding part 172 of the IR holder 160 is sandwiched between sliding rails 201 and 401 with respect to the optical axis direction. The IR holder 160 is engaged only with the arm 301 of the IR meter 300, but the movement of the IR holder 160 in the optical axis direction is restricted by the slide rail 201.401. The sliding portion 172 may be completely sandwiched in order to eliminate the backlash and the fall of the IR holder 160, but a slight gap is provided in this embodiment in order to reduce the load during sliding.

  FIG. 13 shows a state when the IR meter 300 is energized and the IR holder 160 moves to the same position as shown in FIG. FIG. 14 shows a state where the IR holder 160 is further moved from the position shown in FIG. 13 and moved to the same position as that shown in FIG. At this time, the IR cut filter 161 is out of the optical path range AX, and a dummy glass is inserted instead. When the dummy glass is removed from the optical path range AX and the IR cut filter 161 is inserted, the IR holder 300 is driven in the order shown in FIGS. 161 is inserted.

  In the embodiments from FIG. 6 to FIG. 14, the description has been given using the IR holder 160 having the dummy glass. However, the same holder is used in the IR holder 180 having no dummy glass because the holder uses common parts. It is possible to switch to

  As described above, according to the present embodiment, since there is no support member on one side of the IR cut filter, it is possible to provide a lens barrel and an optical apparatus that do not lose an image when the filter is switched. Further, since there is no support member, the fourth moving frame (FIG. 1) holding the lens L4 can be closer to the IR cut filter side, and the optical apparatus can be downsized in the optical axis direction. Furthermore, the present invention can also be applied to a lens barrel having no dummy glass, and even in such a case, it is possible to use this as a common part without changing the shape of the IR holder 160.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

  For example, in the present embodiment, an example using an IR cut filter and a dummy glass has been described, but a combination of an ND filter and a dummy glass having an optical characteristic that changes light transmittance, an IR cut filter and an ND filter, and the like. May be. Further, the present invention can be applied even when there are three or more optical filters.

160 IR holder 161 IR cut filter 162 Dummy glass

Claims (7)

In a lens barrel having an insertion / removal means for inserting / removing at least one optical element on the optical path,
The insertion / removal means has a holder for holding the optical element,
The holder is a combination of a plurality of divided holders,
A lens barrel characterized in that the split holder is provided with a groove for slidingly inserting the optical element.   The lens barrel according to claim 1, wherein the split holder is provided with an adhesive portion that bonds a plurality of the holders in combination.   The lens barrel according to claim 2, wherein the bonding portion bonds the plurality of holders and the at least one optical element.   The lens barrel according to claim 1, wherein one side of the optical element is exposed.   The lens barrel according to claim 1, wherein the groove holds three sides of the optical element.   6. The optical element according to claim 1, wherein the optical element is an IR cut filter having an optical characteristic for cutting infrared rays, or an ND filter having an optical characteristic for changing light transmittance. Lens barrel.   An optical apparatus comprising the lens barrel according to any one of claims 1 to 6.

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