JP2011180410A - Optical instrument - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately control the position of a moving lens frame driven by a stepping motor.
A first moving frame that holds an optical element and is driven by a driving force from a driving unit in the optical axis direction, and a driving force that holds the optical element and is driven from a driving unit in the optical axis direction. A second moving frame that moves in an optical axis, absolute position detecting means that detects an absolute position of the first moving frame in the optical axis direction, and a relative position that detects a relative position in the optical axis direction of the second moving frame. The detection means, the first moving frame, and the second moving frame have interference ranges that overlap in both movable ranges, and the second moving frame has a mechanical end in the interference range. And detecting the position of the first moving frame in the optical axis direction by detecting an output change from the relative position detecting means.
[Selection] Figure 5

Description

  The present invention relates to an optical device, and more particularly to an optical device having a plurality of movable lens groups in a digital still camera, a video camera, or the like that can exchange lenses or has a lens integrally.

  2. Description of the Related Art Conventionally, some imaging devices and interchangeable lens devices have a lens moved in the optical axis direction by an actuator such as a voice coil motor or a stepping motor. Among these, in the lens barrel including the zoom lens, the variator lens group and the focus lens group move in the optical axis direction. A lens position control device is known that controls the position of each lens group by tracking adjustment in a lens barrel in which the variator lens group and the focus lens group move in the optical axis direction (Patent Document 1).

  In recent years, along with the miniaturization of lens barrels and optical devices used therefor, lens groups other than the variator lens group and the focus lens group (shift lens group, etc.) are also moved in the optical axis direction. Then, when moving the lens group in the optical axis direction, position control can be performed by tracking adjustment, and other lens groups other than the variator lens group and the focus lens group must also be position-controlled in order to place them at the design position. No longer. At this time, a photo interrupter is known as one of position detecting means for driving and controlling the lens group with a stepping motor.

Japanese Patent Laid-Open No. 08-220414

  In general, a photo interrupter has a large tolerance variation and its position detection accuracy or mounting accuracy is worse than, for example, an MR sensor. For this reason, it is difficult to arrange the lens group at the optimum design position. Therefore, if an MR sensor or the like is provided in place of the photo interrupter in order to increase the position detection accuracy, a sensor magnet must be disposed at a position facing the MR sensor. Then, the position detection becomes highly accurate, but the lens barrel becomes large and the configuration becomes complicated.

  An object of the present invention is to provide an optical apparatus capable of controlling the position of a lens group with a simple configuration with high accuracy and with a reduction in size.

  An optical apparatus of the present invention holds a first moving frame that holds an optical element and is driven by a driving force from a driving unit in the optical axis direction, and holds the optical element from the driving unit in an optical axis direction. A second moving frame that moves with the driving force, an absolute position detecting means that detects an absolute position of the first moving frame in the optical axis direction, and a relative position in the optical axis direction of the second moving frame that is detected. The relative position detecting means, the first moving frame and the second moving frame have an interference range overlapping within both movable ranges, and the second moving frame has a mechanical end portion within the interference range. And detecting the position of the first moving frame in the optical axis direction by detecting an output change from the relative position detecting means.

  According to the present invention, the position control of the moving lens frame driven by the stepping motor can be performed with high accuracy.

The perspective view of the optical apparatus (camera) of the Example of this invention 1 is an exploded perspective view of a lens barrel provided in the camera of FIG. Sectional view of the lens barrel of FIG. Block diagram of the lens barrel of FIG. 7 is a flowchart showing position detection means for the shift movement frame and the focus movement frame in the lens barrel that is Embodiment 1 of the present invention. Sectional drawing which shows the positional relationship of the shift movement frame and focus movement frame in the lens barrel of Example 1. Sectional drawing which shows the positional relationship of the shift movement frame and focus movement frame in the lens barrel of Example 1. 7 is a flowchart showing position detection means for the shift movement frame and the focus movement frame in the lens barrel that is Embodiment 2 of the present invention. Sectional drawing which shows the positional relationship of the shift movement frame and focus movement frame in the lens barrel of Example 2. Sectional drawing which shows the positional relationship of the shift movement frame and focus movement frame in the lens barrel of Example 2. 9 is a flowchart showing position detection means for a shift movement frame and a focus movement frame in a lens barrel, which is Embodiment 3 of the present invention. Sectional drawing which shows the positional relationship of the shift movement frame and focus movement frame in the lens barrel of Example 3.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the optical apparatus of the present invention, for example, when the first moving frame is a zooming lens group, the start position (reference position) when zooming the first moving frame by a preset design value from the origin position is set. Move. Then, zooming is performed by moving the first moving frame from the reference position. The origin position is detected by a photo interrupter (absolute position detecting means) provided for the first moving frame. Therefore, the first moving frame is set due to manufacturing errors. If there is an error in the origin position, the first moving frame cannot be moved to the correct reference position even if the design value is moved from there.

  It is an object of the present invention to accurately set the first moving frame at the reference position when moving the first moving frame in the optical axis direction. For this reason, the optical apparatus of the present invention holds the optical element (third lens unit) L3 and serves as a driving means for the optical axis direction, for example, a first moving frame (shift) that is step-driven by a driving force from the stepping motor 301. (Moving frame) 3. Further, a second moving frame (focus moving frame) 4 that holds the optical element (fourth lens unit) L4 and moves in the optical axis direction by the driving force from the driving means (voice coil motors 401 to 403). And have. Also, an absolute position detection unit including an absolute position detection unit (light-shielding unit) 307 for absolute position detection provided in the first moving frame 3 and a sensor 306 provided in the rear barrel 6 so as to face the absolute position detection unit 307. Have means.

  Here, the relative position detection means has a configuration with higher position detection accuracy than the absolute position detection means.

  A relative position detecting unit (sensor magnet) 404 for detecting a relative position provided in the second moving frame 4 and a sensor (MR sensor) 405 provided in the rear barrel 6 so as to face the relative position detecting unit 404 are included. Relative position detection means is provided. The first moving frame 3 and the second moving frame 4 have interference ranges that overlap in both movable ranges, and the second moving frame 4 has a mechanical end portion in the interference range. The position detection of the first moving frame 3 and the second moving frame 4 is performed as follows. The first moving frame 3 is retracted from the interference range. The light of the second moving frame 4 when the second moving frame 4 abuts the mechanical end contact portion 406 of the second moving frame 4 on the mechanical end stopper portion 601 of the rear barrel 6 within the interference range. The relative position detection means detects the axial position.

  Thereafter, the first moving frame 3 is returned to the interference range, and is brought into contact with the stopper portion 310 of the first moving frame 3 and the contact portion 407 of the second moving frame 4. The position of the first moving frame 3 in the optical axis direction is detected by detecting an output change from the relative position detecting means when the second moving frame 4 is displaced in the optical axis direction. At the mechanical end portion within the interference range of the second moving frame 4, the mechanical end contact portion 406 of the second moving frame 4 is in contact with the mechanical end stopper portion 601 of the rear barrel 6. At this time, the self-holding force of the second moving frame 4 is reduced or eliminated. Further, from the position (FIG. 7) where the first moving frame 3 is detected by the relative position detecting means (404, 405) to the position where the first moving frame 3 is detected by the absolute position detecting means (306, 307). Storage means 12 for storing data based on the amount of movement.

  Specifically, when the first moving frame 3 is set to a predetermined position (reference position) in the optical axis direction, the following is performed.

  The first moving frame 3 is moved to the image side (− direction) and brought into contact with a part of the second moving frame 4. At this time, the position of the first moving frame 3 is detected by a highly accurate relative position detecting means for detecting the second moving frame 4. At this time, the position of the first moving frame 3 in the optical axis direction is a correctly detected value.

  Next, the first moving frame is moved to the object side (+ direction), and the amount of movement to the position (origin position) detected by the absolute position detecting means is obtained. If there is no manufacturing error at the origin position of the first moving frame 3, the moving amount at this time coincides with a preset design value. If the amount of movement does not match the design value, the difference between the amount of movement and the design value at this time becomes an error in manufacturing the origin position of the first moving frame. In the present invention, the first moving frame 3 is moved from the origin position by setting the error obtained at this time, and the first moving frame 3 is set as the reference position.

  FIG. 1 is a diagram showing a configuration of an optical apparatus (hereinafter referred to as a camera) such as a video camera or a digital camera according to an embodiment of the present invention. L represents a lens barrel capable of zooming, and B represents a camera body. In the camera body B, a silver salt film or an image sensor for recording a subject image formed by the photographing optical system in the lens barrel L is housed.

[Example 1]
Hereinafter, the configuration of the lens barrel L according to the first embodiment of the present invention will be described with reference to FIGS. 2 and 3. In FIG. 2, the directions of arrows X and −X indicate the same direction as the optical axis direction. The photographing optical system is a variable magnification optical system (zoom lens system) composed of four lens units L1 to L4.

  In these drawings, L1 is a first lens unit, and L2 is a second lens unit that performs a zooming action by moving in the optical axis direction during zooming. L3 shifts in a direction orthogonal to the optical axis of the imaging optical system (hereinafter referred to as the optical axis orthogonal direction), moves the image in a direction perpendicular to the optical axis, and image shake occurs when the imaging optical system vibrates. And a third lens unit that can move in the optical axis direction during zooming. L4 is a fourth lens unit that corrects image plane fluctuations accompanying zooming by moving in the optical axis direction and performs a focus adjustment action (focus).

  Reference numeral 1 denotes a first lens frame that holds the first lens unit L1, and 2 denotes a variator moving frame that holds the second lens unit L2. Reference numeral 3 denotes a shift movement frame that holds the third lens unit L3, and reference numeral 4 denotes a focus movement frame that holds the fourth lens unit L4. Reference numeral 5 denotes a fixed barrel, and 6 denotes a rear barrel. The fixed barrel 5 has a rear end coupled to the rear barrel 6 and a front end fixed to the first lens frame 1 in order to fix the first lens unit L1 at a predetermined position. A CCD holder 7 holds an image pickup device (photoelectric conversion device) such as a CCD sensor or a CMOS sensor (not shown), and is fixed to the rear barrel 6.

  Reference numerals 8 a and 8 b denote a first guide bar and a second guide bar, both ends of which are held by the fixed barrel 5 and the rear barrel 6. Reference numerals 9a and 9b denote third and fourth guide bars, and 10a and 10b denote fifth and sixth guide bars. The third and fourth guide bars 9 a and 9 b and the fifth and sixth guide bars 10 a and 10 b are held at both ends by the rear barrel 6 and the CCD holder 7. The variator moving frame 2 is supported by the first and second guide bars 8a and 8b so as to be movable in the optical axis direction. The shift moving frame 3 is supported by the third and fourth guide bars 9a and 9b so as to be movable in the optical axis direction. One ends of the third and fourth guide bars 9 a and 9 b are fixed to the rear barrel 6. Further, a light amount adjustment unit that changes the amount of light incident on a photographing optical system (not shown) is also fixed to the rear barrel 6. The light quantity adjustment unit has two or more diaphragm blades, and moves the diaphragm blades in the direction orthogonal to the optical axis to change the aperture diameter.

  Further, the light quantity adjustment unit (not shown) is configured such that a gradation ND filter (not shown) can advance and retreat with respect to the optical path independently of the aperture blade. The focus moving frame 4 is supported by the fifth and sixth guide bars 10a and 10b so as to be movable in the optical axis direction.

  Next, the configuration of the drive unit that moves the variator moving frame 2 (second lens unit L2) will be described. Reference numeral 201 denotes driving means for driving the variator moving frame 2 in the optical axis direction, for example, a stepping motor. A lead screw 202 is formed on the output shaft of the stepping motor 201. This stepping motor 201 is fixed to the rear barrel 6 via a support member 203. A rack 204 attached to the variator moving frame 2 is engaged with the lead screw 202. For this reason, when the stepping motor 201 is energized and the lead screw 202 rotates, the variator moving frame 2 is driven in the optical axis direction via the rack 204.

  The rack 204 and the variator moving frame 2 are prevented from rattling in the optical axis direction by the biasing force of the torsion coil spring 205. Reference numeral 206 denotes a zoom reset for detecting the reference position of the variator moving frame 2, and detects the switching between the light shielding state and the light transmitting state due to the movement of the light shielding portion 207 formed in the variator moving frame 2 in the optical axis direction. It is comprised by the photointerrupter. The zoom reset 206 is fixed to the rear barrel 6 via the substrate. The variator moving frame 2 holds a sensor magnet 208 that is multipolarly magnetized in the optical axis direction. An MR sensor 209 that reads a change in magnetic field lines accompanying the movement of the sensor magnet 208 is fixed at a position facing the sensor magnet 208 in the rear barrel 6. By using the signal from the MR sensor 209, the amount of movement of the variator moving frame 2, that is, the second lens unit L2, from the predetermined reference position in the optical axis direction can be detected.

  Next, the configuration of the drive unit (drive unit) that moves the shift moving frame 3 that holds the third lens unit (optical element) L3 will be described. Reference numeral 301 denotes driving means for driving the shift moving frame 3 in the optical axis direction, for example, a stepping motor. A lead screw 302 is formed on the output shaft of the stepping motor 301. The stepping motor 301 is fixed to the rear barrel 6 via a support member 303. A rack 304 attached to the shift moving frame 3 is engaged with the lead screw 302.

  Therefore, when the stepping motor 301 is energized and the lead screw 302 rotates, the shift moving frame 3 is driven in the optical axis direction via the rack 304. Note that the rack 304 and the shift moving frame 3 are prevented from rattling in the optical axis direction by the biasing force of the torsion coil spring 305. Reference numeral 306 denotes a sensor (zoom reset) that constitutes a part of absolute position detecting means for detecting the reference position of the shift moving frame 3.

  The zoom reset 306 is configured by a photo interrupter that detects switching between a light shielding state and a light transmitting state due to movement of the light shielding unit (absolute position detection unit) 307 formed in the shift movement frame 3 in the optical axis direction. The zoom reset (sensor) 306 is fixed to the rear barrel 6 via the substrate. Furthermore, switching between the zoom reset 306 configured by a photo interrupter and the light shielding / transmission state of the light shielding unit 307 is within the movable range of the shift moving frame 3 and outside the movable range of the focus moving frame 4. Set to be detected at times. Here, the absolute position detection unit (light-shielding unit: 307) provided in the first moving frame (3) and the sensor (306) provided at a position facing the absolute position detection unit constitute absolute position detection means. ing.

  Next, the configuration of the focus drive unit (drive means) that moves the focus movement frame 4 that holds the fourth lens unit (optical element) L4 will be described. Reference numerals 401, 402, and 403 denote a drive coil, a drive magnet, and a yoke member for closing a magnetic flux that constitute a focus motor (voice coil motor) as a drive unit that drives the fourth lens unit L4 in the optical axis direction. The drive coil 401 is attached to the focus movement frame 4. The drive magnet 402 is provided in the yoke member 403, and the yoke member 403 is attached to the CCD holder 7.

  Here, when a current is passed through the drive coil 401, a Lorentz force is generated by repulsion between the magnetic lines generated between the magnet 402 and the drive coil 401, and the fourth lens unit L4 moves in the optical axis direction together with the focus moving frame 4. Driven. The focus moving frame 4 holds a relative position detector (sensor magnet 404) magnetized in the multi-axis direction in the optical axis direction, which constitutes a part of the relative position detector. A sensor (MR sensor 405) that reads a change in the lines of magnetic force accompanying the movement of the sensor magnet 404 is fixed at a position facing the sensor magnet 404 in the rear barrel 6. Here, the relative position detector (sensor magnet: 404) provided in the second moving frame (4) and the sensor (405) provided at a position facing the relative position detector constitutes a relative position detector. .

  By using the signal from the MR sensor 405, it is possible to detect the relative movement amount from the predetermined reference position in the optical axis direction of the focus moving frame 4, that is, the fourth lens unit L4. The focus moving frame 4 is energized to the drive coil 401 and moves in the direction of the subject, that is, in the direction of the arrow X parallel to the optical axis, and the mechanical end contact portion 406 provided on the focus moving frame 4 The state in contact with the end stopper 601 is detected as a reference position.

  As described above, in the configuration of the focus driving unit, Lorentz force is generated in a state where the coil 401 is energized (hereinafter referred to as energized state), and the focus moving frame 4 is driven in the optical axis direction. However, in a state where the coil 401 is not energized (hereinafter referred to as a non-energized state), the driving force to the focus movement frame 4 is not generated, and the focus movement frame 4 itself has no self-holding force. Become. The self-holding force is a force that can stop the movable coil 401 and further the focus moving frame 4 provided with the coil 401 in a non-energized state.

  In this embodiment, a photo interrupter or an MR sensor is used as the absolute position detection means and the relative position detection means, but a photo reflector, a magnetic sensor, or the like can be applied as other means.

  In each embodiment of the present invention, the movable range of the moving frame refers to the imaging side from the position where the mechanical end abutting portion on the object side is in contact with the mechanical end abutting portion provided in another component in each moving frame. It is the range to the position where the mechanical end of this is contact | abutted with the mechanical end contact part of other components. For example, in the first moving frame (3), an object-side mechanical end (not shown) provided on the first moving frame (3) comes into contact with a mechanical end contact portion provided on the rear barrel 6 (not shown). The starting position. From this starting point to the position where a mechanical end stopper portion (311) on the imaging side, which will be described later, is in contact with the shift contact portion (701). The second moving frame (4) is focused on the imaging side mechanical end contact portion (408), which will be described later, from the position where the object side mechanical end contact portion (406) contacts the mechanical end stopper portion (601). Up to the position where it comes into contact with the contact portion (702).

  In each embodiment, the interference range refers to, for example, a range from the state of FIG. 7 to the state of FIG.

  Next, a method for detecting the positions of the shift movement frame (first movement frame) 3 and the focus movement frame (second movement frame) 4 in the present embodiment will be described with reference to FIGS. 4, 5, 6, and 7. FIG. . In FIG. 4, 11 is a control means for outputting a control signal to the drive means (stepping motor) 201, the stepping motor 301, the drive coil 401, etc. according to the output signal from the zoom reset 206 and the mode of the imaging apparatus main body. . The control means 11 is composed of a microcomputer or the like, and is configured not only to control each operation described above but also to control all the operations in the embodiment. Reference numeral 12 denotes storage means for storing mode information of the control means 11.

  In addition, the structure of the drive means (stepping motor) 201 of a present Example is the same as the stepping motor 201 of another figure. FIG. 5 is a flowchart of the position detection method of the shift movement frame 3 and the focus movement frame 4 in the present embodiment. 6 and 7 are cross-sectional views showing the positional relationship between the shift movement frame 3 and the focus movement frame 4 in this embodiment. Reference numeral 310 denotes a stopper portion provided in the shift movement frame 3, and reference numeral 407 denotes a contact portion provided in the focus movement frame 4. The stopper portion 310 and the contact portion 407 are in positions where they abut each other within the movable range (interference range), and the stopper portion 310 and the contact portion 407 are within the movable range of the shift moving frame 3 and the focus moving frame 4. It is provided so that there is an abutting interference range.

  Then, as shown in FIG. 7, the shift movement frame 3 and the focus movement frame 4 can move while the stopper portion 310 and the contact portion 407 are in contact with each other. At this time, the focus movement frame 4 is pushed by the shift movement frame 3 to move. However, when the normal operation is performed when the shift movement frame 3 and the focus movement frame 4 are energized, the stopper portion 310 and the contact portion 407 are set so as not to contact each other. Reference numeral 406 denotes a mechanical end abutting portion provided on the focus movement frame 4, and reference numeral 601 denotes a mechanical end stopper portion provided on the rear barrel 6. The mechanical end contact portion 406 and the mechanical end stopper portion 601 are provided at positions where they abut each other. The position where the mechanical end contact portion 406 and the mechanical end stopper portion 601 are in contact is the mechanical end of the focus movement frame 4 on the object side of the focus movement frame 4, that is, the arrow X direction side.

  When the mode for detecting the positions of the shift movement frame 3 and the focus movement frame 4 is executed, the operation of Step 1001 in FIG. 5 is performed. When the operation of step 1001 is performed, the shift moving frame 3 is retracted from the interference range. At this time, the shift moving frame 3 is configured such that the zoom reset 306 provided in the rear barrel 6 that detects the reference position of the shift moving frame 3 moves in the optical axis direction (X direction) and the light shielding state and the light transmitting state of the light shielding unit 307. Move to the position to detect the change of. When the operation of step 1001 is completed, the process proceeds to step 1002. In step 1002, when the shift moving frame 3 moves to a position where the zoom reset (photo interrupter) 306 detects the switching between the light blocking state and the light transmitting state of the light blocking unit 307 provided in the shift moving frame 3, the origin of the shift moving frame 3 is moved. Perform position detection. Then, the counter of the step in the stepping motor of the shift movement frame 3 is reset to be the origin of the shift movement frame 3. When the operation of step 1002 is completed, the process proceeds to step 1003.

  Step 1003 moves the focus moving frame 4 to the object side, that is, the mechanical end on the arrow X direction side (position where the mechanical end contact portion 406 and the mechanical end stopper portion 601 are in contact). When the operation of step 1003 is completed, the process proceeds to step 1004. In step 1004, the origin position of the focus moving frame 4 is detected, and the counter of the sensor magnet 404 of the focus moving frame 4 is reset to be the origin of the focus moving frame 4. When the operation of step 1004 is completed, the process proceeds to step 1005. In step 1005, the self-holding force of the focus moving frame 4 is made stronger than the moving force of the focus moving frame 4 due to the tilt of the camera body. Further, even after the shift movement frame 3 comes into contact with the stopper portion 310 and the contact portion 407, the shift movement frame 3 is reduced to a force weaker than the force to move in the arrow -X direction. As a result, the focus movement frame (second movement frame) 4 is pushed by the shift movement frame (first movement frame) 3 to move. Alternatively, when the camera body is horizontal or tilted toward the stopper portion 310, that is, in the direction of the arrow X, and the focus moving frame 4 does not move in the optical axis direction even if the focus moving frame 4 does not have a self-holding force, The self-holding force of the moving frame 4 is eliminated.

  FIG. 6 shows the positional relationship between the shift movement frame 3 and the focus movement frame 4 in the state where the steps up to step 1005 are performed. When the operation of step 1005 is completed, the process proceeds to step 1006. Step 1006 returns the shift moving frame 3 to the interference range, and counts the number of pulses of the stepping motor until the output of the MR sensor 405 provided in the rear barrel 6 changes in the imaging side, that is, in the arrow -X direction. Move while. FIG. 7 shows a position where the output of the MR sensor 405 of the rear barrel 6 changes when the shift movement frame 3 moves. The focus movement frame 4 immediately after the contact portion 407 of the focus movement frame 4 shown in FIG. 7 and the stopper portion 310 of the shift movement frame 3 abuts is moved together with the shift movement frame 3 instantaneously. This is the position where the shift frame 3 is moved to the position in the direction of the arrow -X. When the operation of step 1006 is completed, the process proceeds to step 1007. In step 1007, the counted pulses from the origin position (origin position in the X direction) of the shift movement frame 3 set in step 1002 to the stop position (contact position) of the shift movement frame 3 in step 1006 (FIG. 7). The number, that is, the amount of movement is detected. When the operation of step 1007 is completed, the process proceeds to step 1008. In step 1008, data determined in advance based on the movement amount of the shift movement frame 3 obtained in step 1007 and a value calculated from the movement amount are stored in the storage unit 12. When the operation of step 1008 is completed, the mode for position detection is ended.

  Here, in step 1001, the shift moving frame 3 is moved to a position where the output of the photo interrupter 306 is changed (retracted from the interference range), but other than the movable range of the focus moving frame 4 (interference range). As long as it is outside). In that case, the origin resetting operation of the shift moving frame 3 performed in Step 1002 is performed between Step 1006 and Step 1007. Further, the number of pulses is counted from the stop position of the shift movement frame 3 in step 1006, and the shift movement frame 3 is moved to a position where the output of the photo interrupter 306 is changed in the X direction.

  Thereby, the control means 11 can perform position control of the shift movement frame 3 in the optical axis direction based on the origin determined by the zoom reset 306 from the movement amount stored in the storage means 12. Furthermore, by using the MR sensor 405 provided in the rear barrel 6 for detecting the position of the shift moving frame 3 in the optical axis direction, it is easy to reduce the size without adding the number of parts, and shift movement with higher accuracy. The position of the frame 3 can be detected.

[Example 2]
Hereinafter, with reference to FIGS. 4, 6, 8, 9, and 10, a position detection method for the shift movement frame 3 and the focus movement frame 4 according to the second embodiment of the present invention will be described. Since the basic configuration of the lens barrel L is the same as that of the first embodiment, the description thereof is omitted. Furthermore, the same numbers are assigned to the components described up to FIG.

  In the present embodiment, the first moving frame 3 has a mechanical end contact portion 311. Further, the rear barrel 6 has a fixing member (CCD holder) 7 having a mechanical end (shift contact portion) 701. The first moving frame 3 and the second moving frame 4 have an interference range that overlaps within both movable ranges. The second moving frame 4 has a mechanical end within the interference range. The first moving frame 3 is brought into contact with the stopper portion 310 of the first moving frame 3 and the abutting portion 407 of the second moving frame 4 within the interference range to move both to the fixed member side. The first moving frame 3 stops moving when the mechanical end contact portion 311 provided on the first moving frame 3 contacts the mechanical end portion (shift contact portion) 701 provided on the fixing member (CCD holder) 7. . At this time, the amount of change in the output from the relative position detecting means is detected to detect the position of the first moving frame. The subsequent steps are the same as in the first embodiment.

  FIG. 8 is a flowchart of a position detection method for the shift movement frame 3 and the focus movement frame 4 in the present embodiment. 9 and 10 are sectional views showing the positional relationship between the shift movement frame 3 and the focus movement frame 4 in this embodiment. Reference numeral 311 denotes a mechanical end contact portion provided in the shift movement frame 3, and reference numeral 701 denotes a shift contact portion (contact portion) provided in the CCD holder 7. The mechanical end abutting portion 311 and the shift abutting portion 701 are provided at positions where they abut each other. The position where the mechanical end contact portion 311 and the shift contact portion 701 are in contact is the mechanical end of the shift movement frame (first movement frame) 3 at the position where it stops on the imaging side. Reference numeral 408 denotes a mechanical end contact portion provided on the focus moving frame 4, and reference numeral 702 denotes a focus contact portion provided on the CCD holder 7. The mechanical end contact portion 408 and the focus contact portion 702 are provided at positions where they abut each other. The position where the mechanical end contact portion 408 of the focus moving frame 4 and the focus contact portion 702 of the CCD holder 7 are in contact is the mechanical end on the imaging side of the focus moving frame 4.

  When the mode for detecting the positions of the shift movement frame 3 and the focus movement frame 4 is executed, the operation of step 1009 in FIG. 8 is performed. When the operation of step 1009 is performed, the shift movement frame 3 moves out of the movable range of the focus movement frame 4. When the operation of step 1009 is completed, the process proceeds to step 1010. Step 1010 moves the focus moving frame 4 to the object side, that is, the mechanical end on the arrow X direction side (position where the mechanical end contact portion 406 and the mechanical end stopper portion 601 are in contact). When the operation of step 1010 is completed, the process proceeds to step 1011. Step 1011 detects the origin position of the focus movement frame 4 and resets the counter of the sensor magnet 404 of the focus movement frame 4 to be the origin.

  When the operation of step 1011 is completed, the process proceeds to step 1012. In step 1012, the self-holding force of the focus moving frame 4 is made stronger than the force of moving the focus moving frame 4 due to the tilt of the camera body. Further, even after the shift movement frame 3 comes into contact with the stopper portion 310 and the contact portion 407, the shift movement frame 3 is reduced to a force weaker than the force to move in the arrow -X direction. As a result, the focus movement frame 4 is pushed by the shift movement frame 3 and moves. Alternatively, when the camera body is horizontal or tilted toward the stopper portion 310, that is, in the direction of the arrow X, and the focus moving frame 4 does not move in the optical axis direction even if the focus moving frame 4 does not have a self-holding force, The self-holding force of the moving frame 4 is eliminated.

  FIG. 6 shows the positional relationship between the shift movement frame 3 and the focus movement frame 4 in the state where the steps up to Step 1012 are performed. When the operation of step 1012 is completed, the process proceeds to step 1013. Step 1013 moves the shift moving frame 3 in the direction of the arrow −X until the mechanical end contact portion 311 on the imaging side contacts the shift contact portion 701. When the shift moving frame 3 is moved in the arrow -X direction in step 1013, the stopper portion 310 of the shift moving frame 3 and the abutting portion 407 of the focus moving frame 4 always come into contact with each other as shown in FIG. After that, the shift movement frame 3 moves in the direction of the arrow -X while contacting the focus movement frame 4 as shown in FIG. 9, and the shift movement frame 3 moves to the imaging side (fixed member side), that is, the arrow as shown in FIG. The mechanical end contact portion 311 on the −X direction side contacts the shift contact portion 701. As a result, the shift frame 3 stops.

  When the operation of step 1013 is completed, the process proceeds to step 1014. In step 1014, the origin position of the shift moving frame 3 is detected and the step counter in the stepping motor of the shift moving frame 3 is reset to be the origin. When the operation of step 1014 is completed, the process proceeds to step 1015. In step 1015, the movement amount from the origin position of the focus movement frame 4 to the stop position is stored in the storage unit 12. When the operation of step 1015 is completed, the process proceeds to step 1016. Step 1016 moves the shift frame 3 while counting the number of pulses of the stepping motor from the position where the imaging side mechanical end contact part 311 in FIG. 10 is in contact with the shift contact part 701. Specifically, the zoom reset 306 moves in the direction of the arrow X to a position where the output change of the photo interrupter occurs.

  When the operation of step 1016 is completed, the process proceeds to step 1017. Step 1017 detects the counted number of pulses from the origin position of the shift movement frame 3 in Step 1014 to the stop position of the shift movement frame 3 in Step 1016, that is, the movement amount of the shift movement frame 3. When the operation of step 1017 is completed, the process proceeds to step 1018. In step 1018, data predetermined based on the movement amount and a value calculated from the movement amount are stored in the storage unit 12. When the operation of step 1018 is completed, the mode for position detection is ended.

  Thereby, the control means 11 can perform position control of the shift movement frame 3 with reference to the origin determined by the zoom reset 306 from the movement amount stored in the storage means 12. Furthermore, by using the MR sensor 405 provided in the rear barrel 6 for detecting the position of the shift moving frame 3, it is possible to reduce the size without adding the number of parts, and to further accurately position the shift moving frame 3. Can be detected.

  Specifically, the mechanical end contact portion (406) of the focus moving frame 4 and the mechanical end stopper portion (601) of the rear barrel 6 are in contact, and the stopper portion (310) of the shift moving frame 3 and the focus movement. A state where the contact portion (407) of the frame 4 is in contact is set as a reference position (FIG. 7). At this time, the interference range is as follows. The shift movement frame 3 is moved from the reference position in FIG. 7 to the imaging side, the focus movement frame 4 is pushed and moved by the shift movement frame 3 (FIG. 9), and the mechanical end contact portion (311) of the shift movement frame 3 is moved. ) And the state where the shift contact portion (701) of the CCD holder 7 contacts (FIG. 10).

[Example 3]
Hereinafter, with reference to FIG. 4, FIG. 9, FIG. 11, and FIG. 12, the position detection method of the shift movement frame and the focus movement frame according to the third embodiment of the present invention will be described. Since the basic configuration of the lens barrel L is the same as that of the first embodiment, the description thereof is omitted. Furthermore, the same numbers are assigned to the components described up to FIG.

  The first moving frame 3 is retracted from the interference range, the second moving frame 4 is positioned within the interference range, and then the first moving frame 3 is returned to the interference range. Then, the relative position detection means when the second moving frame 4 is instantaneously moved in the optical axis direction is brought into contact with the stopper portion 310 of the second moving frame 3 and the contact portion 407 of the second moving frame 4. By detecting the output change from the position of the first moving frame 3, the position of the first moving frame 3 in the optical axis direction is detected. The subsequent steps are the same as in the first embodiment.

  FIG. 11 is a flowchart of a position detection method for the shift movement frame 3 and the focus movement frame 4 in this embodiment. FIG. 12 is a cross-sectional view showing the positional relationship between the shift movement frame 3 and the focus movement frame 4 in this embodiment. When the mode for detecting the positions of the shift movement frame 3 and the focus movement frame 4 is executed, the operation of Step 1019 in FIG. 11 is performed. In step 1019, the shift movement frame 3 is moved out of the movable range of the focus movement frame 4. When the operation of step 1019 is completed, the process proceeds to step 1020. In step 1020, the focus moving frame 4 is moved to the object side mechanical end (position where the mechanical end contact portion 406 and the mechanical end stopper portion 601 are in contact).

  When the operation of step 1020 is completed, the process proceeds to step 1021. In step 1021, the origin position of the focus movement frame 4 is detected, and the sensor counter of the focus movement frame 4 is reset to the origin. When the operation of step 1021 is completed, the process proceeds to step 1022. In step 1022, the focus moving frame 4 is in a range where the shift moving frame 3 can be contacted (in the interference range), that is, the stopper 310 of the shift moving frame 3 and the contact portion 407 of the focus moving frame 4 are in contact. Move within the possible range. When the operation of step 1022 is completed, the process proceeds to step 1023. In step 1023, the movement amount from the origin position (step 1021) of the focus movement frame 4 to the stop position is stored in the storage unit 12. When the operation of step 1023 is completed, the process proceeds to step 1024.

  In step 1024, the self-holding force of the focus moving frame 4 is made stronger than the moving force of the focus moving frame 4 due to the tilt of the camera body. Further, even after the shift movement frame 3 comes into contact with the stopper portion 310 and the contact portion 407, the shift movement frame 3 is reduced to a force weaker than the force to move in the arrow -X direction. Alternatively, if the camera body is tilted horizontally, or in the direction of arrow X or arrow -X, and the focus moving frame 4 does not move in the optical axis direction even if the focus moving frame 4 does not have a self-holding force, the focus movement is performed. The self-holding force of the frame 4 is eliminated. FIG. 12 shows the positional relationship between the shift movement frame 3 and the focus movement frame 4 in the state where the steps up to step 1024 are performed. When the operation of step 1024 is completed, the process proceeds to step 1025. In Step 1025, the shift moving frame 3 is moved in the imaging side, that is, in the arrow -X direction while pushing the focus moving frame 4. Then, it moves until the output of the MR sensor 405 changes due to the positional relationship between the sensor magnet 404 provided in the focus moving frame 4 and the MR sensor 405 of the rear barrel 6.

  When the operation of step 1025 is completed, the process proceeds to step 1026. In step 1026, the origin position of the shift moving frame 3 is detected, and the step counter in the stepping motor of the shift moving frame 3 is reset to be the origin. When the operation of step 1026 is completed, the process proceeds to step 1027. In step 1027, the shift moving frame 3 is moved in the arrow X direction from the origin position to a position where the output of the photo interrupter, which is the zoom reset 306, is changed while counting the stepping motor pulses. When the operation of step 1027 is completed, the process proceeds to step 1028. Step 1028 detects the counted number of pulses from the origin position of the shift movement frame 3 in Step 1026 to the stop position of the shift movement frame 3 in Step 1027, that is, the movement amount. When the operation of step 1028 is completed, the process proceeds to step 1029. Step 1029 stores data predetermined based on the movement amount and a value calculated from the movement amount in the storage unit 12. When the operation of step 1029 is completed, the mode for position detection ends.

  Thereby, the control means 11 can perform position control of the shift movement frame 3 with reference to the origin determined by the zoom reset 306 from the movement amount stored in the storage means 12. Furthermore, by using the MR sensor 405 provided in the rear barrel 6 for detecting the position of the shift moving frame 3, it is possible to reduce the size without adding the number of parts, and to further accurately position the shift moving frame 3. Can be detected.

  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.

L Lens barrel B Camera body 3 Shift moving frame 4 Focus moving frame 306 Zoom reset 310 Stopper 404 Sensor magnet 405 MR sensor 406 Mechanical end contact portion 407 Contact portion 601 Mechanical end stopper portion

Claims (7)

  A first moving frame that holds the optical element and is driven by the driving force from the driving unit in the optical axis direction, and a first moving frame that holds the optical element and moves by the driving force from the driving unit in the optical axis direction. Two moving frames, absolute position detecting means for detecting the absolute position of the first moving frame in the optical axis direction, and relative position detecting means for detecting the relative position of the second moving frame in the optical axis direction; The first moving frame and the second moving frame have an interference range that overlaps within both movable ranges, the second moving frame has a mechanical end within the interference range, and the relative An optical apparatus that detects the position of the first moving frame in the optical axis direction by detecting a change in output from the position detecting means.   The relative position detecting means retracts the first moving frame from the interference range, brings the second moving frame into contact with the mechanical end within the interference range, and then moves the first moving frame within the interference range. The position of the first moving frame in the optical axis direction is detected by detecting an output change when the second moving frame is displaced in the optical axis direction. The optical apparatus according to claim 1.   The relative position detecting means retracts the first moving frame from the interference range, positions the second moving frame in the interference range, and then returns the first moving frame to the interference range. 2. The position of the first moving frame in the optical axis direction is detected by detecting an output change when the second moving frame is displaced in the optical axis direction by contacting the second moving frame. 1 optical instrument.   The first moving frame has a mechanical end abutting portion, a fixing member having an abutting portion abutting on the mechanical end abutting portion, and a second movement within the interference range of the first moving frame. The first moving frame is brought into contact with the frame and moved to the fixed member side, and the movement of the first moving frame is stopped by the contact of the mechanical end contacting portion provided on the first moving frame with the contacting portion provided on the fixing member. At this time, the optical apparatus according to claim 1, wherein the position of the first moving frame is detected by detecting a change amount of the output from the relative position detecting means.   5. The self-holding force of the second moving frame is reduced or eliminated at a mechanical end portion in the interference range of the second moving frame. 5. The optical instrument described.   Storage means for storing data based on a movement amount from a position at which the first moving frame is detected by the relative position detecting means to a position at which the first moving frame is detected by the absolute position detecting means; The optical apparatus according to claim 1, wherein:   The optical apparatus according to claim 1, wherein the relative position detection unit has a configuration with higher position detection accuracy than the absolute position detection unit.