Imaging lens device and imaging device

Abstract

To provide, for example, an imaging lens device advantageous for reduction in the movement of movable frames in a non-energized state.SOLUTION: An imaging lens device has: a first movable frame including a first optical element, a second movable frame including a second optical element, and a third movable frame including a third optical element, which are arranged in order along an optical axis; a first driving unit that moves the first movable frame in an optical axis direction, and holds a position of the first movable frame in a non-energized state; a second driving unit that moves the second movable frame in the optical axis direction, and does not hold a position of the second movable frame in the non-energized state; a third driving unit that moves the third movable frame in the optical direction, and holds a position of the third movable frame in the non-energized state; and a control unit that controls the first, second, and third driving units. The control unit moves at least a part of at least one of the first and third movable frames into a movable range of the second movable frame, and subsequently controls the second driving unit from an energized state to the non-energized state.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present invention relates to an imaging lens device and an imaging device. [Background technology]

[0002] 2. Description of the Related Art A lens barrel in an optical device such as a video camera performs zooming and focusing by moving a moving frame that holds a lens in the direction of an optical axis using a driving force from a driving source.

[0003] A stepping motor, a voice coil motor, or the like is used as a drive unit (drive source) for moving the moving frame in the optical axis direction. The voice coil motor does not generate a force (self-holding force) to keep the moving frame stationary when the power is turned off and the motor is in a non-energized state.

[0004] Therefore, in the de-energized state, the optical element and moving frame move due to their own weight and inertial force, and the moving frame may collide with a member (end member) that limits its movable range. Patent Document 1 discloses a lens barrel having a first moving frame that moves using a self-retaining drive source in the de-energized state, a second moving frame that moves using a non-self-retaining drive source in the de-energized state, and a shock absorbing part provided on the first moving frame. Furthermore, in the lens barrel of Patent Document 1, in the de-energized state, a portion of the first moving frame is controlled to be positioned within the movable range of the second moving frame, thereby narrowing the movable range of the second moving frame, thereby reducing the impact of a collision. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-128594 Summary of the Invention [Problem to be solved by the invention]

[0006] Even if the shock-absorbing structure and the range of motion of the second moving frame are limited, it is difficult to suppress the generation of collision noise with the mechanical end because the second moving frame moves due to changes in posture, etc. when not powered on.

[0007] SUMMARY OF THE INVENTION An object of the present invention is to provide an imaging lens device that is advantageous in reducing the movement of a moving frame in a non-energized state, for example. [Means for solving the problem]

[0008] The imaging lens device of the present invention includes a first moving frame including a first optical element, a second moving frame including a second optical element, and a third moving frame including a third optical element, all arranged in that order along an optical axis; a first driving unit that moves the first moving frame in the optical axis direction and maintains the position of the first moving frame in a non-energized state; a second driving unit that moves the second moving frame in the optical axis direction and does not maintain the position of the second moving frame in a non-energized state; a third driving unit that moves the third moving frame in the optical axis direction and maintains the position of the third moving frame in a non-energized state; and a control unit that controls the first driving unit, the second driving unit, and the third driving unit, and is characterized in that the control unit controls the second driving unit from a powered state to a non-powered state after moving at least a portion of at least one of the first moving frame and the third moving frame into a movable range of the second moving frame. [Effects of the Invention]

[0009] According to the present invention, for example, it is possible to provide an imaging lens device that is advantageous in reducing movement of a moving frame in a non-energized state. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a cross-sectional view of an imaging lens device according to a first embodiment. [Figure 2] FIG. 2 is a perspective view of a drive unit according to the first embodiment. [Figure 3] FIG. 2 is an exploded perspective view of the drive unit in the first embodiment, as viewed from the object side. [Figure 4]FIG. 2 is an exploded perspective view of the drive unit in the first embodiment, as viewed from the image plane side. [Figure 5] FIG. 2 is a front view of the drive unit according to the first embodiment. [Figure 6] 6 is a cross-sectional view taken along line UU in FIG. 5, showing the reference position of the second moving frame in the first embodiment. FIG. [Figure 7] 6 is a cross-sectional view taken along line VV in FIG. 5, showing a restricted state of the second moving frame in the first embodiment. FIG. [Figure 8] 4 is a flowchart showing a control mode when no current is applied in the first embodiment. [Figure 9] FIG. 10 is a cross-sectional view of the entire lens barrel in Example 2. [Figure 10] FIG. 10 is a perspective view of a drive unit according to a second embodiment. [Figure 11] FIG. 10 is an exploded perspective view of a drive unit according to a second embodiment, as viewed from the object side. [Figure 12] FIG. 10 is an exploded perspective view of a drive unit according to a second embodiment, as viewed from the image plane side. [Figure 13] FIG. 10 is a front view of a drive unit according to a second embodiment. [Figure 14] 14 is a cross-sectional view taken along the line WW in FIG. 13, showing a restricted state of the second moving frame in the second embodiment. FIG. [Figure 15] 10 is a flowchart showing a control mode when no current is applied in the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Preferred embodiments of the present invention will now be described with reference to the drawings. [Example]

[0012] FIG. 1 is a cross-sectional view of a lens barrel 100 according to a first embodiment. Lens barrel 100 includes a variable magnification optical system (zoom lens system) made up of five lens units (lens groups) L1 to L5, each including at least one optical element, a light amount adjustment unit 6, an ND unit 7, and an IR unit 8.

[0013] The first lens unit L1 is stationary in the optical axis direction. The second lens unit L2, the third lens unit (first optical element) L3, and the fifth lens unit (third optical element) L5 move in the optical axis direction to perform zooming. The third lens unit L3 is composed of the third lens unit L3a and the third lens unit L3b, and functions not only as a zooming unit but also as an optical system that corrects image shake. The third lens unit L3b is an anti-vibration lens unit that shifts in a direction perpendicular to the optical axis of the photographic optical system to reduce image shake.

[0014] The fourth lens unit L4 (second optical element) corrects image plane fluctuations that occur with zooming by moving along the optical axis, and also functions as a focus lens group that adjusts focus by moving along the optical axis.

[0015] The first holding frame 1 holds the first lens unit L1. The L2 moving frame 2 holds the second lens unit L2. The first moving frame 3 holds the 3a lens unit L3a, and the vibration-proof moving frame 30 holds the 3b lens unit L3b. The vibration-proof moving frame 30 is attached to the first moving frame 3 so as to be movable in a direction perpendicular to the optical axis. The second moving frame 4 holds the fourth lens unit L4. The third moving frame 5 holds the fifth lens unit L5.

[0016] The front end of the front fixed barrel 9 is connected to the first holding frame 1 to fix the first lens unit L1 in a predetermined position, and the rear end of the front fixed barrel 9 is connected to the rear fixed barrel 11, which will be described later.

[0017] The central fixed barrel 10 holds a light intensity adjustment unit 6, and its rear end is connected to a rear fixed barrel 11, which will be described later. The light intensity adjustment unit 6 adjusts the light intensity by moving the diaphragm blades in a plane perpendicular to the optical axis using a drive unit (not shown), thereby changing the aperture diameter of the optical system.

[0018] The front end of rear fixed barrel 11 is connected to front fixed barrel 9 and central fixed barrel 10, and the rear end is connected to second holding frame 12, which will be described later.

[0019] The front end of the second holding frame 12 is connected to the rear fixed lens barrel 11, and houses the ND unit 7, IR unit 8, and an image sensor (not shown). The ND unit 7 reduces the amount of light using a filter because adjusting the light intensity solely by changing the aperture area of ​​the iris reduces the aperture opening when photographing a high-brightness subject, resulting in degradation of optical performance due to light diffraction. The IR unit 8 has an infrared light cut filter located in front of the optical axis of the image sensor when used in the visible light range, which cuts out near-infrared light, and a mechanism for removing the infrared light cut filter when used in the near-infrared light range.

[0020] The image pickup element (not shown) is an image pickup section that photoelectrically converts the subject image formed by each of the first to fifth lens units L1 to L5.

[0021] The first guide bar (not shown) is held at both ends by the front fixed lens barrel 9 and the central fixed lens barrel 10. The second guide bar 13 is held at both ends by the front fixed lens barrel 9 and the rear fixed lens barrel 11. The L2 moving frame 2 is supported by the first guide bar and the second guide bar 13 so as to be movable in the optical axis direction. Hereinafter, the components of the drive unit 200 according to the first embodiment will be described in detail with reference to FIGS.

[0022] In the drive unit 200 according to the first embodiment of the present invention, FIG. 2 is an overall perspective view, FIG. 3 is an exploded perspective view seen from the object side, FIG. 4 is an exploded perspective view seen from the image side, FIG. 5 is a front view, FIG. 6 is a cross-sectional view taken along line UU in FIG. 5, and FIG. 7 is a cross-sectional view taken along line VV in FIG. 5. The first moving frame 3 (first moving frame) has a first stopper portion 310 (first restricting portion) that protrudes toward the second moving frame 4 (second moving frame) in the optical axis direction. The third guide bar 14a and the fourth guide bar 14b are held at their respective ends by the central fixed lens barrel 10 and the rear fixed lens barrel 11. The first moving frame 3 is supported by the third guide bar 14a and the fourth guide bar 14b so as to be movable in the optical axis direction.

[0023] The second moving frame 4 has a first convex portion 406 (first regulated portion) protruding toward the first moving frame 3 in the optical axis direction, a second convex portion 407 (second regulated portion) protruding toward the third moving frame 5, and a third convex portion 408.

[0024] Both ends of the fifth guide bar 15a and the sixth guide bar 15b are held by the central fixed lens barrel 10 and the rear fixed lens barrel 11. The second moving frame 4 is supported by the fifth guide bar 15a and the sixth guide bar 15b so as to be movable in the optical axis direction.

[0025] The third moving frame 5 (third moving frame) has a second stopper portion 510 (second restricting portion) that protrudes toward the second moving frame 4 in the optical axis direction.

[0026] The seventh guide bar 16a and the eighth guide bar 16b are held at their respective ends by the central fixed lens barrel 10 and the rear fixed lens barrel 11. The third moving frame 5 is supported by the seventh guide bar 16a and the eighth guide bar 16b so as to be movable in the optical axis direction.

[0027] Next, the configuration of the drive unit that moves the first moving frame 3 will be described. A first stepping motor 301 (first drive unit) drives the first moving frame 3 in the optical axis direction. A first lead screw 302 is formed on the output shaft of the first stepping motor 301. The first stepping motor 301 is fixed to the rear fixed barrel 11 via a first support member 303. A first rack 304 attached to the first moving frame 3 engages with the first lead screw 302. Therefore, when the first stepping motor 301 is energized and the first lead screw 302 rotates, the first moving frame 3 is moved in the optical axis direction via the first rack 304.

[0028] The first rack 304 and the first moving frame 3 have their rattle reduced in the optical axis direction by the biasing force of the first torsion coil spring 305 .

[0029] When the first stepping motor 301 is not energized (de-energized state), the first moving frame 3 has a self-holding force because the first rack 304 and the first lead screw 302 are engaged with each other.

[0030] The first reset 306 is a zoom reset for detecting the reference position of the first moving frame 3, and is a photointerrupter for detecting switching between a light-blocking state and a light-transmitting state due to movement in the optical axis direction of a first light-blocking portion 307 formed on the first moving frame 3. The first reset 306 is fixed to the rear fixed barrel 11 via a substrate (not shown).

[0031] The first scale 308 is a reflective film scale that constitutes an optical position detection encoder, and is held by the first moving frame 3. The first sensor head 309 is a photo IC chip that incorporates a light source equipped with an LED chip and a circuit that processes the signal of the light reflected from the light source by the first scale 308. The first sensor head 309 is fixed via a substrate (not shown) to a position on the rear fixed barrel 11 that faces the first scale 308. The signal from the first sensor head 309 is used to detect the amount of movement of the first moving frame 3 from a predetermined reference position (first reset 306).

[0032] Next, the configuration of the drive unit that moves the second moving frame 4 will be described. The voice coil motor (second drive unit) is composed of a drive coil 401, a drive magnet 402, and a yoke member 403 for closing the magnetic flux. The drive coil 401 is attached to the second moving frame 4. The drive magnet 402 is provided inside the yoke member 403, which is attached to the rear fixed barrel 11. When a current is passed through the drive coil 401 (when energized), a Lorentz force is generated between the drive magnet 402 and the drive coil 401 due to the repulsion of magnetic lines of force. The Lorentz force generated at this time drives the second moving frame 4 in the optical axis direction. When the drive coil 401 is not energized (non-energized state), no drive force is generated on the second moving frame 4, and the second moving frame 4 does not have any holding force with respect to its position in the optical axis direction.

[0033] The second scale 404 is a reflective film scale constituting an optical position detection encoder and is held by the second moving frame 4. The second sensor head 405 is a photo IC chip incorporating a light source equipped with an LED chip and a circuit for signal processing of light reflected from the light source by the second scale 404. The second sensor head 405 is fixed via a substrate (not shown) to a position on the rear fixed barrel 11 facing the second scale 404. The signal from the second sensor head 405 is used to detect the amount of movement of the second moving frame 4 from a predetermined reference position. Here, the reference position of the second moving frame 4 refers to the position of the second moving frame 4 when a third protrusion 408, which serves as the end (mechanical end) of the movable range of the second moving frame 4 in the optical axis direction, abuts against a third stopper portion 111 of the rear fixed barrel 11, as shown in FIG. 6.

[0034] Next, the configuration of the drive unit that moves the third moving frame 5 will be described. A second stepping motor 501 (third drive unit) drives the third moving frame 5 in the optical axis direction. A second lead screw 502 is formed on the output shaft of the second stepping motor 501. The second stepping motor 501 is fixed to the rear fixed barrel 11 via a second support member 503. A second rack 504 attached to the third moving frame 5 engages with the second lead screw 502. Therefore, when the second stepping motor 501 is energized and the second lead screw 502 rotates, the third moving frame 5 is moved in the optical axis direction via the second rack 504.

[0035] The second rack 504 and the third moving frame 5 have their rattle reduced in the optical axis direction by the biasing force of the second torsion coil spring 505. When the second stepping motor 501 is not energized (de-energized state), the third moving frame 5 has a self-holding force because the second rack 504 and the second lead screw 502 are engaged with each other. The second reset 506 is a zoom reset for detecting the reference position of the third moving frame 5, and is a photointerrupter for detecting the switching between the light-blocking state and the light-transmitting state due to the movement of the second light-shielding portion 507 formed on the third moving frame 5 in the optical axis direction.

[0036] The second reset 506 is fixed to the rear fixed barrel 11 via a substrate (not shown). The third scale 508 is a reflective film scale that constitutes an optical position detection encoder, and is held by the third moving frame 5 .

[0037] The third sensor head 509 is a photo IC chip that incorporates a light source equipped with an LED chip and a circuit that processes the reflected light from the light source reflected by the third scale 508, and is fixed via a substrate to a position on the rear fixed barrel 11 opposite the third scale 508.

[0038] By using the signal from the third sensor head 509, the amount of movement of the third moving frame 5 from a predetermined reference position (second reset 506) is detected.

[0039] The position of each of the lens units L1 to L5 in the optical axis direction during shooting is determined based on the relationship stored in advance in a storage unit (not shown) with respect to the shooting conditions such as focal length, object distance, etc. A control means (control unit) (not shown) controls the drive units that drive each of the lens units L1 to L5 based on the shooting conditions, and moves each of the lens units L1 to L5 in the optical axis direction.

[0040] Hereinafter, the control mode when an operation to bring about a non-energized state is performed will be described with reference to FIGS. FIG. 8 is a flowchart showing a control mode during non-energization in the first embodiment of the present invention. In FIG. 8, when an operation to turn off the power is performed in step #101, an operation from step #102 is started by a control means (not shown) such as a microcomputer located in the camera body or lens barrel.

[0041] In step #102, the third moving frame 5 is moved to a position (P1) outside the movable range on the image side (-Y direction) of the second moving frame 4. Here, the movable range of the second moving frame 4 refers to the structural movable range of the second moving frame 4. This operation ensures free movement space for the second moving frame 4 to move toward the image side in the next step #103.

[0042] In step #103, the second moving frame 4 is moved to a position (P2) on the image side (-Y direction) of the first moving frame 3 and outside the imaging movement range of the first moving frame 3.

[0043] In step #104, the first moving frame 3 is moved to a position (P3) closest to the image side (in the -Y direction) within the movable range of the first moving frame 3. At this time, P3 is within the movable range of the second moving frame 4.

[0044] In step #105, the second moving frame 4 is moved to a certain position (P4) until the first stopper portion 310 of the first moving frame 3 and the first protrusion 406 of the second moving frame 4 come into contact with each other.

[0045] In step #106, the third moving frame 5 is moved toward the object side (Y direction). At this time, the second stopper portion 510 of the third moving frame 5 comes into contact with the second convex portion 407 of the second moving frame 4. Here, the movement of the third moving frame 5 toward the object side reaches outside the optically used imaging movement range in which the third moving frame 5 moves during imaging (outside the imaging movement range).

[0046] In step #107, the position of the second moving frame 4 is detected by the second scale 404 and the second sensor head 405, and it is determined whether or not the position of the second moving frame 4 has changed.

[0047] If the result of the judgment is that the position of the second moving frame 4 has changed, that is, if there is a gap or play between the second moving frame 4 in the optical axis direction and the first moving frame 3, return to step #106 and repeat the same operation.

[0048] On the other hand, if it is determined in step #107 above that the position of the second moving frame 4 has not changed, that is, if there is no gap or play between the second moving frame 4 and the first moving frame 3 in the optical axis direction, proceed to step #108, stop driving the third moving frame 5, and return to the state shown in Figure 7.

[0049] In step #109, the first stepping motor 301, the voice coil motors (401 to 403), and the second stepping motor 501 are de-energized, and the control mode ends.

[0050] At this time, the first stopper portion 310 and the first convex portion 406, and the second stopper portion 510 and the second convex portion 407 come into contact with each other, thereby restricting the movement of the second moving frame 4 in the optical axis direction, and the position of the second moving frame 4 in the optical axis direction is maintained even when power is not applied.

[0051] Furthermore, the configuration in the optical axis direction may be reversed from the configuration explained in the flowchart of the first embodiment, and the effects of the present invention can be similarly enjoyed. In step #106, the third moving frame 5 is moved toward the object side, and the second stopper portion 510 of the third moving frame 5 is brought into contact with the second convex portion 407 of the second moving frame 4, but the present invention is not limited to this. The effect of reducing collision noise can also be achieved by moving the third moving frame 5 toward the object side, and further moving it to outside the shooting movement range, and stopping it before the third moving frame 5 and the second moving frame 4 come into contact, thereby further narrowing the gap between the moving frames.

[0052] The photographing movement range used for photographing the third moving frame 5 may be configured so that part of it overlaps with the movable range of the second moving frame 4, or it may not have an overlapping range.

[0053] In this way, in Example 1, by regulating the second moving frame 4 with the first moving frame 3 and the third moving frame 5, which have self-holding force, it is possible to reduce the generation of collision noise at the mechanical end due to the movement of the second moving frame 4 even in a non-energized state. [Example]

[0054] FIG. 9 is a cross-sectional view of a lens barrel 110 according to a second embodiment of the present invention. Lens barrel 110 includes a variable magnification optical system (zoom lens system) made up of five lens units L1000 to L5000, a light amount adjustment unit 6000, an ND unit 7000, and an IR unit 8000.

[0055] The first lens unit L1000 is stationary in the optical axis direction. The second lens unit L2000 and the third lens unit L3000 have the effect of varying magnification by moving in the optical axis direction.

[0056] The 3rd group lens unit L3000 is composed of the 3a group lens unit L3000a and the 3b group lens unit L3000b, and not only varies the magnification but also serves as an optical system for image stabilization.

[0057] The 3b group lens unit L3000b is an image stabilizing lens unit that reduces image blur by shifting in a direction perpendicular to the optical axis of the imaging optical system.

[0058] The fourth lens unit L4000 moves in the optical axis direction to correct image plane fluctuations that occur with magnification changes and to adjust focus. The fifth lens unit L5000 is stationary in the optical axis direction. The first holding frame 1000 holds the first lens unit L1000. The L2 moving frame 2000 holds the second lens unit L2000. The first moving frame 3000 holds the 3a lens unit L3000a.

[0059] The vibration-isolating moving frame 30000 holds the 3b group lens unit L3000b. The vibration-isolating moving frame 30000 is attached to the first moving frame 3000 so as to be movable in a direction perpendicular to the optical axis. The second moving frame 4000 holds the fourth lens unit L4000. The rear fixed barrel (fixed member) 11000 holds the fifth lens unit L5000. The front end of the front fixed barrel 9000 is fixed to the first holding frame 1000, and fixes the first lens unit L1000 in a predetermined position. The rear end of the front fixed barrel 9000 is connected to the rear fixed barrel 11000.

[0060] The central fixed barrel 10000 holds the light intensity adjustment unit 6000 and its rear end is connected to the rear fixed barrel 11000 . The light intensity adjustment unit 6000 adjusts the light intensity by moving the diaphragm blades in a plane perpendicular to the optical axis using a drive unit (not shown) to change the aperture diameter of the optical system. The front end of the rear fixed barrel 11000 is connected to the front fixed barrel 9000 and the middle fixed barrel 10000, and its rear end is connected to a second holding frame 12000 (described below). The front end of the second holding frame 12000 is connected to the rear fixed barrel 11000, and houses the ND unit 7000, the IR unit 8000, and an image sensor (not shown).

[0061] If the ND unit 7000 adjusts the amount of light only by changing the area of ​​the aperture, the aperture will become smaller when photographing a highly bright subject, resulting in degradation of optical performance due to the phenomenon of light diffraction. Therefore, the ND unit 7000 reduces the amount of light using a filter.

[0062] When used in the visible light range, the IR unit 8000 has an infrared light cut filter that cuts out near-infrared light placed in front of the optical axis of the image sensor, and has a mechanism for removing the infrared light cut filter when used in the near-infrared light range.

[0063] The image sensor (not shown) is an image pickup section that photoelectrically converts the subject image formed by each of the first to fifth lens units L1000 to L5000.

[0064] The first guide bar and second guide bar 13000 (not shown) are held at their ends by the front fixed barrel 9000, the middle fixed barrel 10000 and the rear fixed barrel 11000.

[0065] The L2 moving frame 2000 is supported by a first guide bar and a second guide bar 13000 so as to be movable in the optical axis direction.

[0066] Hereinafter, the components of the drive unit 210 according to the second embodiment will be described in detail with reference to FIGS.

[0067] In a drive unit 210 according to a second embodiment of the present invention, FIG. 10 is an overall perspective view, FIG. 11 is an exploded perspective view seen from the object side, FIG. 12 is an exploded perspective view seen from the image side, FIG. 13 is a front view, and FIG. 14 is a WW cross-sectional view of FIG. 13.

[0068] The first moving frame 3000 (first moving frame) has a first stopper portion 3010 (first restricting portion) that protrudes toward the second moving frame 4000 (second moving frame) in the optical axis direction. The third guide bar 14000a and the fourth guide bar 14000b are held at their respective ends by the central fixed lens barrel 10000 and the rear fixed lens barrel 11000. The first moving frame 3000 is supported by the third guide bar 14000a and the fourth guide bar 14000b so as to be movable in the optical axis direction.

[0069] The second moving frame 4000 (second moving frame) has a first convex portion 4006 (first regulated portion) protruding toward the first moving frame 3000 in the optical axis direction and a second convex portion 4007 (second regulated portion) protruding toward the rear fixed barrel 11000.

[0070] The fifth guide bar 15000a and the sixth guide bar 15000b are held at their respective ends by the central fixed barrel 10000 and the rear fixed barrel 11000. The second moving frame 4000 is supported by the fifth guide bar 15000a and the sixth guide bar 15000b so as to be movable in the optical axis direction. The rear fixed barrel 11000 has a second stopper portion 11001 (second restricting portion) that protrudes toward the second moving frame 4000 in the optical axis direction.

[0071] Next, the configuration of the drive unit that moves the first moving frame 3000 will be described. A stepping motor 3001 (first drive unit) drives the first moving frame 3000 in the optical axis direction. A lead screw 3002 is formed on the output shaft of the stepping motor 3001. The stepping motor 3001 is fixed to the rear fixed barrel 11000 via a support member 3003. A rack 3004 attached to the first moving frame 3000 engages with the lead screw 3002. Therefore, when the stepping motor 3001 is energized and the lead screw 3002 rotates, the first moving frame 3000 is moved in the optical axis direction via the rack 3004.

[0072] The rattle between the rack 3004 and the first moving frame 3000 in the optical axis direction is reduced by the biasing force of the torsion coil spring 3005. When the stepping motor 3001 is not energized (de-energized state), the first moving frame 3000 has a self-holding force because the rack 3004 and the lead screw 3002 are engaged with each other.

[0073] The reset 3006 is a zoom reset for detecting the reference position of the first moving frame 3000, and is a photointerrupter for detecting switching between a light-blocking state and a light-transmitting state due to movement in the optical axis direction of a light-blocking portion 3007 formed on the first moving frame 3000. The reset 3006 is fixed to the rear fixed barrel 11000 via a substrate (not shown).

[0074] The first scale 3008 is a reflective film scale that constitutes an optical position detection encoder, and is held by the first moving frame 3000. The first sensor head 3009 is a photo IC chip that incorporates a light source equipped with an LED chip and a circuit that processes the signal of the light reflected from the light source by the first scale 3008. The first sensor head 3009 is fixed via a substrate (not shown) to a position on the rear fixed barrel 11000 that faces the first scale 3008. The signal from the first sensor head 3009 is used to detect the amount of movement of the first moving frame 3000 from a predetermined reference position (reset 3006).

[0075] Next, the configuration of the drive unit that moves the second moving frame 4000 will be described. The voice coil motor (second driving unit) is composed of a driving coil 4001, a drive magnet 4002, and a yoke member 4003 for closing the magnetic flux. The driving coil 4001 is attached to a second moving frame 4000. The drive magnet 4002 is provided inside the yoke member 4003, and the yoke member 4003 is attached to the rear fixed barrel 11000.

[0076] When a current is passed through the drive coil 4001 (when it is energized), a Lorentz force is generated between the drive magnet 4002 and the drive coil 4001 due to the repulsion of magnetic lines of force. The Lorentz force at this time drives the second moving frame 4000 in the optical axis direction. When the drive coil 4001 is not energized (non-energized state), no driving force is generated on the second moving frame 4000, and the second moving frame 4000 does not have any holding force with respect to its position in the optical axis direction.

[0077] The second scale 4004 is a reflective film scale that constitutes an optical position detection encoder, and is held by the second moving frame 4000. The second sensor head 4005 is a photo IC chip that incorporates a light source equipped with an LED chip and a circuit that processes the signal of the light reflected from the light source by the second scale 4004. The first sensor head 3009 is fixed via a substrate (not shown) to a position on the rear fixed barrel 11000 that faces the second scale 4004. The amount of movement of the second moving frame 4000 from a predetermined reference position is detected by using a signal from the second sensor head 4005.

[0078] Here, the reference position of the second moving frame 4000 refers to the position of the second moving frame 4000 when the second convex portion 4007 abuts against the second stopper portion 11001 of the rear fixed barrel 11000, which is the end (mechanical end) of the movable range of the second moving frame 4000 in the optical axis direction, as shown in Figure 14.

[0079] Hereinafter, the control mode when an operation to bring about a non-energized state is performed will be described with reference to FIGS. FIG. 15 is a flowchart showing a control mode during non-energization in the second embodiment of the present invention.

[0080] When an operation to turn off the power (power OFF operation) is performed in step #1001, operation from step #1002 is started by a control means (not shown) such as a microcomputer located in the camera body or lens barrel.

[0081] In step # 1002 , the second moving frame 4000 is moved to a certain position (P 10 ) until the second stopper portion 11001 abuts (contacts) the second convex portion 4007 .

[0082] In step #1003, the first moving frame 3000 is moved toward the image side (-Z direction). At this time, the first stopper portion 3010 and the first convex portion 4006 come into contact with each other. Note that this contacting position of the first moving frame 3000 is located outside the range in which the first moving frame 3000 moves during imaging (outside the imaging movement range).

[0083] In step #1004, the position of the second moving frame 4000 is detected by the second scale 4004 and the second sensor head 4005, and it is determined whether the position of the second moving frame 4000 has changed. If it is determined that the position of the second moving frame 4000 has changed, the process returns to step #1003 and repeats the same operations. On the other hand, if it is determined in step #1004 that the position of the second moving frame 4000 has not changed, this means that there is no play or gap between the moving frame and the rear fixed barrel 11000 between each moving frame. In this case, the process proceeds to step #1005, where the first moving frame 3000 is stopped, resulting in the state shown in FIG. 14.

[0084] In step #1006, the stepping motor 3001 and the voice coil motors (4001 to 4003) are de-energized, and the control mode ends. At this time, the first stopper portion 3010 and the first convex portion 4006, and the second stopper portion 11001 and the second convex portion 4007 come into contact with each other, restricting the second moving frame 4000, and maintaining the optical axis position of the second moving frame 4000 even in the de-energized state.

[0085] In this way, in the second embodiment, by restricting the second moving frame 4000 with the first moving frame 3000 having a self-holding force and the rear fixed barrel 11000, it is possible to suppress the generation of collision noise at the mechanical end due to the movement of the second moving frame 4000 even in a non-powered state.

[0086] In the flow of Example 2 in the flowchart of Figure 15, the first moving frame 300 is moved out of the imaging movement range on the image side, and the position of the second moving frame 4000 is maintained by sandwiching it between the rear fixed barrel 11000. However, the present invention is not limited to this. Even if the first moving frame 3000 is moved out of the imaging movement range and the second moving frame 4000 is not sandwiched, the collision noise can also be reduced by narrowing the movable range of the second moving frame 4000 between the first moving frame 3000 and the rear fixed barrel 11000. Furthermore, the configuration in the optical axis direction may be reversed from the configuration explained in the flowchart of the second embodiment, and the effects of the present invention can be similarly enjoyed.

[0087] Furthermore, by configuring an imaging device that includes the imaging lens device of the present invention and an imaging element that captures an image formed by the imaging lens device, it is possible to provide an imaging device that enjoys the effects of the present invention.

[0088] Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0089] 3: First moving slot 4: Second moving slot 5: Third moving slot 301: First stepping motor (first driving unit) 401: Drive coil (second drive unit) 402: Drive magnet (second drive unit) 403: Yoke member (second driving part) 501: Second stepping motor (third drive unit) L3: 3-group lens unit (first optical element) L4: 4-group lens unit (second optical element) L5: 5-group lens unit (third optical element)

Claims

1. a first moving frame including a first optical element, a second moving frame including a second optical element, and a third moving frame including a third optical element, which are arranged in this order along the optical axis; a first driving unit that moves the first moving frame in the optical axis direction and maintains the position of the first moving frame in a non-energized state; a second driving unit that moves the second moving frame in the optical axis direction and does not maintain the position of the second moving frame in a non-energized state; a third driving unit that moves the third moving frame in the optical axis direction and maintains the position of the third moving frame in a non-energized state; a control unit that controls the first drive unit, the second drive unit, and the third drive unit, the control unit controls the second drive unit from a powered state to a non-powered state after moving at least a portion of at least one of the first moving frame and the third moving frame into a movable range of the second moving frame.

2. 2. The imaging lens device according to claim 1, wherein the control unit controls the second drive unit to change from a powered state to a non-powered state after moving at least one of the first moving frame and the third moving frame outside a movement range for imaging and into the movable range.

3. 3. The imaging lens device according to claim 1, wherein the control unit controls the second drive unit from a powered state to a non-powered state after bringing the first moving frame and the second moving frame into contact with each other and bringing the second moving frame and the third moving frame into contact with each other.

4. a first moving frame including a first optical element, a second moving frame including a second optical element, and a fixed member, which are arranged in this order along the optical axis; a first driving unit that moves the first moving frame in the optical axis direction and maintains the position of the first moving frame in a non-energized state; a second driving unit that moves the second moving frame in the optical axis direction and does not maintain the position of the second moving frame in a non-energized state; a control unit that controls the first drive unit and the second drive unit, the control unit controls the second drive unit from a powered state to a non-powered state after moving at least a part of the first moving frame outside a movement range for image capture and into a movable range of the second moving frame.

5. 5. The imaging lens device according to claim 4, wherein the control unit controls the second drive unit from a powered state to a non-powered state after bringing the first moving frame and the second moving frame into contact with each other and bringing the second moving frame and the fixed member into contact with each other.

6. 6. The imaging lens device according to claim 1, wherein the first driving unit includes a stepping motor having an output shaft on which a lead screw is formed.

7. 4. The imaging lens device according to claim 1, wherein the third driving unit includes a stepping motor having an output shaft on which a lead screw is formed.

8. 8. The imaging lens device according to claim 1, wherein the second driving section includes a voice coil motor.

9. 9. The imaging lens device according to claim 1, wherein the second optical element moves for focusing.

10. 10. The imaging lens device according to claim 1, wherein the first optical element moves during zooming.

11. 4. The imaging lens device according to claim 1, wherein the third optical element moves during zooming.

12. 4. The imaging lens device according to claim 1, wherein a moving range for imaging of the third moving frame overlaps with the movable range of the second moving frame.

13. An imaging device comprising: the imaging lens device according to claim 1; and an imaging element for capturing an image formed by the imaging lens device.

Images