JP2009157049A - Lens control apparatus, lens barrel, imaging apparatus, and optical apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lens which, while preventing an increase in size, prevents defocusing of a focus lens even when a temperature rise occurs. <P>SOLUTION: A lens control apparatus includes: a temperature detection means (#104) configured to detect a temperature near a zoom lens and the focus lens; a zoom lens drive means configured to drive the zoom lens; and a controller configured, if it is determined that a current temperature near the zoom lens and the focus lens detected by the temperature detection means is higher than a reference temperature (Y in #106), to acquire a telephoto end position of the zoom lens to be set at the current temperature (#107), to compare the telephoto end position with a current position of the zoom lens, and to cause the zoom lens drive means to move the zoom lens to the telephoto end position (#109) if the current position of the zoom lens is located beyond the telephoto end position on a telephoto side (Y in #108). <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a lens control device that performs position control of a zoom lens and a focus lens, a lens barrel, an imaging device including the lens control device, and an optical apparatus.

  2. Description of the Related Art Conventionally, as a lens barrel for a still camera or a video camera, there is known a type in which a zoom lens and a focus lens each having a built-in lens group are driven by a driving member such as a stepping motor.

  In general, when a lens group is driven by a driving member such as a stepping motor, a so-called open loop control system is often employed as a control system for driving and positioning the lens group. In the case of the open loop control method, a detection device for detecting the position of the lens group every moment is unnecessary, and the configuration of the control system is simpler than the control system of the closed loop control method, and This is because it becomes smaller.

  However, when the lens group positioning control is performed by an open loop control method using a stepping motor, it is necessary to match the driving start position of the stepping motor with the movement start position of the lens group. For this purpose, each lens group is provided with a reference position detecting unit for returning the lens group to a specific reference position before starting the positioning control and detecting whether the lens group is positioned at the reference position (reset position). There was a need.

  FIG. 6 is a diagram showing how the position of each lens group is controlled. The horizontal axis is the focal length position of the zoom lens, and the vertical axis is the position of the focus lens. Specifically, the left end of the horizontal axis is the wide end, the right end is the tele end (telephoto end), the lower end of the vertical axis is the infinite position, and the upper end is the closest focus position. Hereinafter, a curve as shown in FIG. 6 is referred to as a “cam locus”.

  In general, the shape of the cam trajectory is like a cam trajectory when the subject distance is infinite. Until then, it becomes a mountain-shaped continuous curve.

  As a feature of the cam trajectory, it is known that the slope from the middle position to the tele end becomes steeper as it approaches the tele end. The steepest slope is represented by “dy / dx” (see FIG. 6) at a position where “the zoom state is tele and the subject distance is infinite”. The large numerical value indicates that the focus lens must be moved greatly with respect to the movement of the zoom lens. In the lower part of FIG. 6, the relationship between optical magnification and tele / infinite cam curve, that is, “dy / dx” is shown.

  2. Description of the Related Art In recent years, in optical devices such as cameras, the lens barrel and the image size of a solid-state image sensor have been rapidly reduced. Further, many plastic materials are used as materials for the lens barrel and the holding member of the optical system. When plastic materials are used as the material for the lens barrel and optical system holding members, these members can be easily molded by the mold, and the shape is highly arbitrary, and the cost advantage compared to other materials There are many advantages, such as being large.

  On the other hand, when a plastic material is used for the lens barrel and the holding member of the optical system, there is a problem that physical properties and dimensional changes are large with respect to environmental changes, particularly temperature changes and humidity changes. For example, if a plastic is used as the structural material of the lens barrel, the focal length, the in-focus position, and the like are greatly changed compared to the case where a metal material is used, resulting in a performance problem that a focus shift occurs.

To solve these problems, a technique has been proposed (Patent Document 1) in which the amount of focus deviation is obtained from a temperature change and the position of the focus lens is corrected.
Japanese Patent No. 3581513

  However, as the optical magnification is increased and the optical system is reduced in size, the steep slope “dy / dx” in the vicinity of the tele end of the cam trajectory described above rapidly increases. Yes. Therefore, when the optical magnification is high, in an optical system in which the zoom / focus lens position is controlled by the cam trajectory, if the position at the telephoto end of the zoom lens shifts even for a small amount for some reason, the shift amount is several tens of times The focus lens must be moved by the amount of.

  The biggest factor causing this defocus is thermal expansion of the lens unit structural member due to temperature rise. When the zoom lens moves in the super-tele direction due to thermal expansion due to this temperature rise, it will not be in focus unless the distance of several tens of times is moved to the mirror surface side of the focus lens (the image sensor side such as a CCD or CMOS). . Therefore, the mechanical dimension of the lens barrel also requires a clearance that is greater than this amount, resulting in a problem that the mechanical total length of the lens barrel is long and large.

(Object of invention)
An object of the present invention is to provide a lens control device, a lens barrel, an imaging device, and an optical device that can prevent the focus lens from being out of focus even when the temperature changes to a high temperature side while preventing an increase in size. It is what.

  In order to achieve the above object, the present invention provides a temperature detection unit that detects temperatures in the vicinity of a zoom lens and a focus lens, a zoom lens drive unit that drives the zoom lens, and a temperature detection unit that is more than a reference temperature. When the detected current temperature is high, the telephoto end position at the current temperature of the zoom lens is acquired, the telephoto end position is compared with the current position of the zoom lens, and the current position of the zoom lens is greater than the telephoto end position. Further, when the zoom lens is at the telephoto position, the lens control device includes a control unit that moves the zoom lens to the telephoto end position by the zoom lens driving unit.

  In order to achieve the above object, the present invention provides a lens barrel, an imaging apparatus, or an optical instrument that includes the lens control device of the present invention.

  According to the present invention, it is possible to provide a lens control device, a lens barrel, an imaging device, or an optical device that can prevent the focus lens from being out of focus even if the temperature changes to a high temperature side while preventing an increase in size. Is.

  The best mode for carrying out the present invention is as shown in Examples 1 and 2 below.

  FIG. 1 is a system configuration diagram illustrating an imaging apparatus such as a video camera including a lens control apparatus according to the first embodiment of the present invention. It is assumed that a plastic material is used as a material for the lens barrel and the holding member of the optical system.

  In FIG. 1, reference numeral 101 denotes a fixed first fixed lens group, reference numeral 102 denotes a zoom lens which is a lens group for zooming, reference numeral 103 denotes a stop, and reference numeral 104 denotes a fixed second fixed lens group. Reference numeral 105 denotes a focus lens which is a lens group having both a focus adjustment function and a so-called competition function for correcting movement of the focal plane due to zooming. A zoom lens driving source 110 drives the zoom lens 102, and a focus lens driving source 111 drives the focus lens 105. The zoom lens driving source 110 and the focus lens driving source 111 each have a stepping motor and a driver unit.

  Reference numeral 106 denotes an image sensor such as a CMOS sensor or a CCD sensor. Reference numeral 107 denotes a camera signal processing circuit which performs signal processing such as converting a signal from the image sensor 106 into a signal corresponding to a recording device 109 described later. Reference numeral 109 denotes a recording device for recording a moving image or a still image. As a recording medium, a magnetic tape, a semiconductor memory, a DVD (Digital Versatile Disk), or the like is used.

  Reference numeral 114 denotes a camera microcomputer that controls the zoom lens drive source 110 and the focus lens drive source 111. Further, according to the AF / MF switch 113 for performing control according to the operation of the zoom switch 112 and switching the driving method of the focus lens 105 to the auto focus mode (AF mode) or the manual focus mode (MF mode). Control. Further, control by an output signal from the camera signal processing circuit 107 is performed. For example, target positions of the zoom lens 102 and the focus lens 105 are calculated, compared with positions detected by a lens position detection unit described later, and the zoom lens driving source 110 and the focus lens driving source 111 are controlled to control each lens. Is moved in the optical axis direction.

  Reference numeral 112 denotes a lens position detector that detects the position of the zoom lens 102, and reference numeral 113 denotes a lens position detector that detects the position of the focus lens 105. Each of the lens position detection units 112 and 113 includes a photosensor and a light shielding plate (both not shown). The photosensor includes a light emitting unit and a light receiving unit. The light shielding plates are a zoom lens 102 and a focus lens 105, respectively. It is fixed to. When the zoom lens 102 and the focus lens 105 are moved in the optical axis direction, the light shielding plate is moved integrally therewith. When the light path between the light emitting unit and the light receiving unit of the photosensor is blocked, the output signal of the light receiving unit is at a low level, and when not blocked, the output signal is at a high (Hi) level. Therefore, it is possible to detect whether or not the zoom lens 102 and the focus lens 105 are present at the reference position, with the position where the output signal of the light receiving unit is changed as the reference position (reset position). The camera microcomputer 114 can recognize the position of each lens based on the reference position, the lens moving speed, the lens moving direction, and the like.

  A thermistor element 108 detects the temperature in the vicinity of the lens barrel containing the first fixed lens group 101, zoom lens 102, diaphragm 103, second fixed lens group 104, and focus lens 105, and uses this as temperature information. Output to the camera microcomputer 114.

  The operation from when the power switch of the camera is turned on until the zoom lens 102 and the focus lens 105 are set to the initial positions is referred to as “lens reset operation”.

  FIG. 2 shows the positions of these lenses when the zoom lens 102 and the focus lens 105 are controlled by the cam locus. The horizontal axis indicates the position of the zoom lens 102 from the wide end to the tele end, and the vertical axis indicates the position. The position of the focus lens 105 is from infinity to the nearest.

  In FIG. 2, a curve 70 is a control position of the zoom lens 102 and the focus lens 105 when the subject distance is infinite. A curved line 71 is a control position of the zoom lens 102 and the focus lens 105 when the subject distance is 1000 mm. Reference numeral 72 denotes an output of the lens position detection unit 112 that is switched depending on an in (Hi) state or an out (Low) state of the light shielding plate of the zoom lens 102. Reference numeral 73 denotes an output of the lens position detection unit 113 that is switched depending on an in (Hi) state or an out (Low) state of the light shielding plate of the focus lens 105. The positions (zoom reset and focus reset) at which Hi → Low are switched are the count reference positions of the stepping motors that drive the zoom lens 102 and the focus lens 105, respectively.

  In the first embodiment, both the zoom lens driving source 110 that drives the zoom lens 102 and the focus lens driving source 111 that drives the focus lens 105 use stepping motors. However, any one of the drive sources may be composed of another drive member such as a VCM (voice coil motor).

  In the imaging apparatus having the lens barrel as described above, it is assumed that a temperature rise (high temperature state) occurs after a power switch (not shown) is turned on and a lens reset operation is performed. Then, as shown in FIG. 3, the telephoto end / infinite position of the zoom lens 102 is shifted by a temperature change by DXt (the difference between the movable range A and B of the lens). Due to this deviation DXt, the focus lens 105 is out of focus by DYt. At the same time, there is a problem that the focal length at the tele end is longer than the original focal length.

  Here, in order to correct the focus shift DYt by the focus lens 105, it is only necessary to move the focus lens 105 by the focus shift DYt. However, in order to carry in, it is necessary to set a clearance equal to or greater than the focus shift DYt. As a result, as described in the section of the problem to be solved by the invention, there arises a problem that the rear end portion of the lens barrel becomes long or a clearance corresponding to the focus deviation DYt cannot be set.

  In order to solve this, the focus shift DYt can be eliminated by correcting the focus shift DYt generated here without moving the focus lens 105 and moving the zoom lens 102 by the shift DXt in the wide direction. . At the same time, the focal length at the tele end becomes the original focal length. In other words, in the “tele end / infinite” state, when a focus shift occurs due to a temperature change (change to a high temperature above a predetermined value), the tele end position of the zoom lens 102 is widened by an amount equivalent to the focus shift. Move in the direction.

  In order to realize this, the thermistor element 108, which is a temperature sensor used to detect whether a temperature rise (high temperature state) has occurred after the power switch is turned on and the lens reset operation is performed, is connected to the lens barrel. It is installed in the vicinity. Then, according to the temperature information from the thermistor element 108, the camera microcomputer 114 moves the tele end position of the zoom lens 102 in the wide direction by the deviation DXt.

  That is, when the temperature rises, the camera microcomputer 114 moves the tele end position of the zoom lens 102 in the wide direction via the zoom lens driving source 110 by the displacement DXt of the zoom lens 102 caused by the temperature rise. As a result, the zoom lens 102 is positioned at the original telephoto end focal length, and the focus lens 105 does not cause a focus shift DYt.

  Next, operations related to lens control in the camera microcomputer 114 will be described with reference to the flowchart of FIG.

  In FIG. 4, when the power switch is turned on in step # 101 and the camera is turned on, the camera microcomputer 114 starts the operation from step # 102. First, in step # 102, t0 that is a reference temperature is captured. The reference temperature t0 is a temperature at normal temperature, and is stored in advance in the flash ROM in the camera microcomputer 114, and the data is loaded into the main body RAM in step # 102. Thereafter, the process proceeds to step # 103, where the initial position operation of the zoom lens 102 and the focus lens 105, that is, the lens reset operation is performed, and the reference position of each lens is detected.

  In the next step # 104, the camera microcomputer 114 takes in the current temperature information detected by the thermistor element 108 via the A / D converter, and converts it into the current temperature tc using a pre-stored temperature conversion table. In the next step # 105, a temperature difference between the current temperature tc and the reference temperature t0 is calculated, and the temperature difference is set to Δt.

  In the next step # 106, the camera microcomputer 114 determines whether the temperature difference Δt in step # 105 is positive or negative. That is, it is determined whether or not the current temperature tc detected in step # 104 is higher than the reference temperature t0, which is the temperature at normal temperature. As a result of the determination, if it is determined that the temperature difference Δt is negative, the process returns to step # 104 and the same operation is repeated.

  On the other hand, if it is determined in step # 106 that the temperature difference Δt is positive, the process proceeds to step # 107 to acquire the tele end position P2 at the current temperature tc. The tele end position acquisition method at the current temperature tc can be acquired, for example, by referring to table data indicating the relationship between the temperature information and the tele end position stored in advance in the storage unit of the camera microcomputer 114. As described with reference to FIG. 3, the tele end position P2 at the current temperature tc is wider than the tele end position P1 at the reference temperature t0.

The difference ΔP between the tele end position P1 at the normal temperature (reference temperature t0) and the tele end position P2 at the current temperature is substantially proportional to the temperature difference Δt. The telephoto end movement amount ΔP is set to ΔP = α × Δt (1)
It may be calculated by the following formula (1). Here, α represents a proportionality constant, and this coefficient is a constant determined by the lens barrel to be used. Using ΔP obtained by the above equation (1), the following equation (2)
P2 = P1−ΔP (2)
Thus, the tele end position P2 at the current temperature tc can be calculated.

  In the next step # 108, it is determined whether or not the current position of the zoom lens 102 is on the tele side from the tele end position P2 of the current temperature tc. As a result of the determination, if it is determined that the current zoom lens 102 is not on the tele side from the tele end position P2 of the current temperature tc, the process returns to step # 104 and the same operation is repeated.

  On the other hand, if it is determined in step # 108 that the current zoom lens 102 is on the tele side from the tele end position P2 of the current temperature tc, the process proceeds to step # 109, and the zoom lens 102 is moved to the tele end position P2. Driven by the driving unit 110.

  The lens control device provided in the camera (imaging device) according to the first embodiment includes the following components.

  The zoom lens 102, the focus lens 105, a thermistor element 108 that detects temperatures in the vicinity of these lenses, and a zoom lens drive source 110 that drives the zoom lens 102. Furthermore, when the current temperature tc detected by the thermistor element 108 is higher than the reference temperature (temperature at normal temperature) t0, the camera microcomputer 114 acquires the tele (telephoto) end position P2 of the zoom lens 102 at the current temperature tc. Have Then, when the camera microcomputer 114 acquires the tele end position P2, the camera microcomputer 114 compares the tele end position P2 with the actual position of the current zoom lens 102. As a result of the comparison, when the current position of the zoom lens 102 is on the tele side with respect to the tele end position P2, the zoom lens 102 is moved to the wide side by the zoom lens driving source 110 to the tele end position P2.

  The camera microcomputer 114 has table data indicating the relationship between the temperature information and the telephoto end position P2 of the zoom lens 102. Then, the tele end position P2 of the zoom lens 102 is acquired from the temperature information detected by the thermistor element 108 and the table data.

  Alternatively, the camera microcomputer 114 calculates a temperature difference (a high temperature equal to or greater than a predetermined value) Δt between the reference temperature and the current temperature tc detected by the thermistor element 108. Then, the tele end position P2 of the zoom lens 102 is calculated by calculation using the temperature difference Δt and a predetermined calculation coefficient (the above formulas (1) and (2)).

  With the above-described configuration, the zoom lens 102 becomes the original telephoto end position, and the clearance of the lens barrel mechanical dimension at the infinite focus position of the focus lens 105 can be secured. There is no need to increase the overall length. That is, even if there is a temperature change on the higher temperature side than the reference temperature, it is not necessary to move the focus lens 105 for focus correction, so that the lens barrel can be prevented from being enlarged. At the same time, even if there is a temperature change, the actual focal length does not change to a longer focal length than the set value due to thermal expansion of the lens barrel. In other words, the focus lens 105 can be prevented from being out of focus even when a temperature change to the high temperature side occurs while preventing an increase in size.

  Next, a second embodiment of the present invention will be described.

  When a stepping motor is used to drive the zoom lens 102, the zoom lens 102 may not be stopped at the intended zoom lens position due to problems of hysteresis and stop resolution. In particular, in the vicinity of the telephoto end position where the movement amount of the focus lens 105 is large relative to the movement amount of the zoom lens, the focus lens position may deviate from the in-focus position, and small blurring may occur in the captured image. In this case, in the AF mode, it is possible to immediately drive the focus lens 105 to the in-focus position even if small blur occurs due to the above-described problem, but this problem is exposed in the MF mode.

  The second embodiment of the present invention is made in view of the above points, and the configuration of the imaging apparatus is the same as that in FIG. The difference from the first embodiment is only the processing of the camera microcomputer 114, which will be described with reference to the flowchart of FIG.

  In FIG. 5, when the power switch is turned on in step # 201, the camera microcomputer 114 starts operation from step # 201. First, in step # 202, t0 that is a reference temperature is captured. The reference temperature t0 is a temperature at normal temperature and is stored in advance in the flash ROM in the camera microcomputer 114, and the data is loaded into the RAM in step # 202. In the next step # 203, the zoom lens 102 and the focus lens 105 are reset, and the reference positions of the respective lenses are detected.

  In the next step # 204, the camera microcomputer 114 takes in the temperature information detected by the thermistor element 108 via the A / D converter, and converts it into the current temperature using a temperature conversion table stored in the main body in advance. Then, in the next step # 205, a temperature difference between the current temperature tc and the reference temperature t0 is calculated, and the temperature difference is set to Δt.

  In the next step # 206, the camera microcomputer 114 determines whether the temperature difference Δt in step # 205 is positive or negative. That is, by this determination, it is determined whether or not the current temperature tc detected in step # 204 is higher than the reference temperature t0 that is the temperature at normal temperature. As a result of the determination, if it is determined that the temperature difference Δt is negative, the process returns to step # 204, and thereafter the same operation is repeated.

  On the other hand, if it is determined in step # 206 that the temperature difference Δt is positive, the process proceeds to step # 207, and the camera microcomputer 114 acquires the tele end position P2 at the current temperature tc. The tele end position acquisition method at the current temperature tc can be acquired, for example, by referring to table data indicating the relationship between the temperature data and the tele end position stored in advance in the storage unit of the camera microcomputer 114. .

Since the tele end position difference ΔP between the tele end position P1 at the normal temperature (reference temperature t0) and the tele end position P2 at the current temperature is substantially proportional to the temperature difference Δt, step # 207 is executed. Then, the tele end movement amount ΔP to the wide side is set to ΔP = α × Δt (1)
It may be calculated by the following equation (1). Here, α represents a proportional constant, and this coefficient is a constant determined by the lens unit barrel portion to be used. Using ΔP obtained by the above equation (1), the following equation (2)
P2 = P1-ΔP (2)
Thus, the current temperature P2 can be calculated.

  In the next step # 208, the camera microcomputer 114 determines whether or not the current position of the zoom lens 102 is on the tele side from the tele end position P2 of the current temperature tc. As a result of the determination, if it is determined that the current zoom lens 102 is not on the tele side from the tele end position P2 of the current temperature tc, the process returns to step # 204 and the same operation is repeated.

  On the other hand, if it is determined in step # 208 that the current zoom lens 102 is on the tele side from the tele end position P2 of the current temperature tc, the process proceeds to step # 209 to determine whether or not the focus mode is the AF mode. Do. As a result, when the AF mode is not set, that is, when the MF mode is set, the process returns to Step # 204 and the same operation is repeated.

  If it is determined in step # 209 that the AF mode is set, the process proceeds to step # 210, and the zoom lens driving unit 110 drives the zoom lens 102 to the telephoto end position P2.

  In the second embodiment, the camera microcomputer 114 performs the same operation as the first embodiment when the driving method of the focus lens 105 is the AF mode. However, in the case of the MF mode, near the telephoto end position where the movement amount of the focus lens 105 is large relative to the movement amount of the zoom lens, the focus position is deviated, and small blurring may occur in the captured image. is there. Therefore, even when the position of the zoom lens 102 is on the tele side with respect to the tele end position P2, the zoom lens drive source 110 is prohibited from moving the zoom lens 102 to the tele end position P2. As described above, in the MF mode, it is prohibited to drive the motor in the vicinity of the telephoto end because the amount of movement of the focus is larger than the amount of movement of the zoom. For this reason, the influence of the variation of the individual lenses and the shift of the focus surface due to the temperature increases, and even if the focus lens is driven according to the design value, the accurate focus position may not be maintained. On the other hand, in the AF mode, even if small blur occurs due to these causes, the focus is immediately adjusted, so that the focus surface can be held.

  As a result, even when a stepping motor is used, it is possible to eliminate the possibility of stopping at the intended zoom lens position due to problems of hysteresis and stop resolution, and to prevent the occurrence of small blur during shooting.

(Correspondence between the present invention and the embodiment)
The zoom lens 102 corresponds to the zoom lens of the present invention, and the focus lens 105 corresponds to the focus lens of the present invention. The thermistor element 108 corresponds to a temperature detecting means for detecting the temperature in the vicinity of the zoom lens and the focus lens of the present invention. The zoom lens driving source 110 corresponds to zoom lens driving means for driving the zoom lens of the present invention. In addition, when the current temperature detected by the temperature detection unit is higher than the reference temperature of the present invention, the camera microcomputer 114 is a control unit that acquires the telephoto end position (tele end position P2) at the current temperature of the zoom lens. Equivalent to. Then, the control means compares the telephoto end position with the current position of the zoom lens, and if the current position of the zoom lens is further on the telephoto side than the telephoto end position, the zoom lens is moved to the telephoto end position. It is moved by driving means.

  In the above-described embodiment, an example in which the present invention is applied to a lens barrel or an imaging device is shown, but the present invention can be similarly applied to a case where the lens control device is configured. The present invention can also be applied to optical equipment such as binoculars equipped with this type of lens control device.

It is a system position block diagram which shows the imaging device which concerns on Example 1 of this invention. It is a figure which shows the mutual relationship of the cam locus | trajectory based on Example 1 of this invention, a zoom reset position, and a focus reset position. It is a figure which shows the relationship between the zoom lens position by the cam locus | trajectory based on Example 1 of this invention, and a focus lens position. It is a flowchart which shows the operation | movement of the part regarding the lens control in the camera microcomputer which concerns on Example 1 of this invention. It is a flowchart which shows the operation | movement of the part regarding the lens control in the camera microcomputer which concerns on Example 2 of this invention. It is a figure which shows the conventional cam locus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 101 1st fixed lens group 102 Zoom lens 103 Diaphragm 104 2nd fixed lens group 105 Focus lens 106 Image pick-up element 107 Camera signal processing circuit 108 Thermistor element 109 Memory | storage device 110 Zoom lens drive source 111 Focus lens drive source 112 Zoom lens position detection part 113 Focus lens position detection unit 114 Camera microcomputer 115 Zoom switch 116 AF / MF off switch

Claims (7)

Temperature detecting means for detecting the temperature in the vicinity of the zoom lens and the focus lens;
Zoom lens driving means for driving the zoom lens;
When the current temperature detected by the temperature detecting means is higher than the reference temperature, the telephoto end position at the current temperature of the zoom lens is acquired, the telephoto end position is compared with the current position of the zoom lens, and the zoom And a control unit that moves the zoom lens to the telephoto end position by the zoom lens driving unit when the current lens position is further on the telephoto side than the telephoto end position. Table data indicating the relationship between the temperature and the telephoto end position of the zoom lens,
The lens control apparatus according to claim 1, wherein the control unit acquires a telephoto end position of the zoom lens from a temperature detected by the temperature detection unit based on the table data.   The control means calculates a temperature difference between the reference temperature and a temperature detected by the temperature detection means, and obtains a telephoto end position of the zoom lens by calculation using the temperature difference. Item 4. The lens control device according to Item 1.   When the focus lens driving method is not the autofocus mode but the manual focus mode, the control means is configured to operate the zoom lens driving means even if the zoom lens is located on the telephoto side from the telephoto end position. 4. The lens control device according to claim 1, wherein movement of the zoom lens to the telephoto end position is prohibited.   A lens barrel comprising the lens control device according to claim 1.   An imaging apparatus comprising the lens control device according to claim 1.   An optical apparatus comprising the lens control device according to claim 1.

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