JP2585804Y2 - Shooting lens device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a photographic lens device, and more particularly, to a photographic lens device having a zoom function and capable of performing macro photography.

[Prior Art] Conventionally, various configurations of a zoom lens in a camera having a zoom function have been provided. As shown in FIG. 11, a typical example of the zoom lens is as shown in FIG. , Focusing lens L ₁ , variator lens
L ₂ , compensator lens L ₃ and relay lens L ₄ 4
It is composed of groups. Lens group directly involved in these zooming, a variator lens L ₂ and the compensator lens L ₃ as is well known, the focusing lens L ₁
Is being moved during the focusing operation, a relay lens L ₄ is serves for imaging the image plane. Normal zooming operation by the zoom cam and the like, as shown and a variator lens L ₂ and the compensator lens L ₃ in FIG. 11 (A), is moved to the imaging side tele, as shown in FIG. 11 (B) subject Move to the side to make it wider.

Then, the macro can not be wider focusing range to move less short distance side of the image even by moving the focusing lens L ₁ in order to perform a macro shooting with this zoom lens, the conventional zoom lens used In the shooting above
From the wide state shown in FIG. 11 (B), the variator lens L ₂ as shown in FIG. 11 (C) is in a fixed state, if a short distance of an object moving toward only compensator lens L ₃ on the imaging side I try to make you scorch. Therefore, the magnification naturally changes in the macro.

The conventional macro mechanism utilizes the zoom cam cylinder that moves the variator lens L ₂ and the compensator lens L _3, as shown in FIG. 12, is formed in the cam barrel 100, the variator lens driving pin 101 cams on each wide end of the cam slot 104 to fit the fitting to the cam slot 102 and the compensator lens driving pin 103, which is the cam barrel 100, respectively a dead region not move the variator lens L ₂ is also rotated in the and interconnects the cam slot 106 of slot 105 and the compensator lens L ₃ is displaced toward the image side, so that provided a zoom region and the macro area in the cam barrel for zooming. Also, AF
In the case of a camera, the AF operation was disabled during macro mode, and the zoom cam barrel provided with a macro area was manually moved to confirm focusing with a viewfinder image.

[Problem to be Solved by the Invention] By the way, in the lens driving of the photographing lens device configured as described above, it is necessary to accurately drive the lens to a predetermined position in order to increase zooming accuracy and focusing accuracy. The manufacturing accuracy and assembling accuracy of the individual components that make up the lens device vary, and improving the above-mentioned zooming and focusing accuracy only by increasing these accuracy is not only technically limited but also cost-effective. It will be very expensive.

Accordingly, an object of the present invention is to provide a high-precision photographic lens device that can be easily adjusted without increasing the manufacturing accuracy and the assembling accuracy of the individual components constituting the above-described conventional photographic lens device. The purpose is to do.

[Means and Actions for Solving the Problems] A photographic lens device according to the present invention includes a means for detecting a preset initial position of a photographic lens when power is turned on;
Means for storing a preset reference position of the macro area of the taking lens, means for detecting the current position of the taking lens based on the initial position of the taking lens, means for measuring the distance to the subject, and Means for driving the lens, and if the measurement result of the distance to the subject corresponds to the micro area, the photographing lens is driven from the reference position of the macro area and the current position of the photographing lens. Drive based on the drive amount to the reference position of the macro area, and if the measurement result of the distance to the subject corresponds to the normal focus area, the photographing lens is driven based on the drive amount of the photographing lens from the current position. It is characterized by being driven.

[Embodiment] Hereinafter, the present invention will be described with reference to an embodiment shown in the drawings.

A zoom lens and its driving mechanism in an electronic camera according to an embodiment of the present invention are configured as shown in FIGS. That is, in order from the object side, the zoom lens has a three-lens focus lens L ₁ held on a movable lens support frame ₁ , a three-lens variator lens L _{2 also} held on a movable lens support frame 2, and a movable lens Compensator lens composed of one convex lens held by the lens support frame 3
L ₃ and a relay lens L ₄ composed of _four lenses held by a stationary lens support frame 4, each being disposed on the lens optical axis O.

Lens support frame 4 holding the relay lens L ₄ is disposed on the lens optical axis O, the stationary fixed frame member 5 having a through-hole 5a of the lens optical axis direction in the central portion, of the through hole 5a A solid-state image sensor 8 composed of a CCD held on a substrate 7 by a support member 6 is fixed to a rear end of the through hole 5a, and is fixed to a front end of the through-hole 5a. so that the subject image by the relay lens L ₄ through a low-pass filter 10 which is held on the support frame 9 into the through-hole 5a is imaged on. Further, the immobility of the fixed frame member aperture device in front of the 5 11 (not shown in FIG. 1) have attached, aperture by the aperture device 11 is formed just before the relay lens L ₄ It has become.

Guide shafts 11a, 11b extending along the optical axis O on the front side of the fixed frame member 5 on the left and right sides of the optical axis O.
The bases of the shafts 11a and 11b are fixedly implanted, and the front ends of the shafts 11a and 11b penetrate through the fixed substrate 12 and are supported by the front fixing member 13. The two guide shafts 11a, 11 arranged in parallel
to b, the compensator lens L ₃ lens holding frame 3 holds the lens supporting frame 2 which holds the variator lens L _2, the lens holding frame 1 which holds the focus lens L ₁ is attached slidably in the front-rear direction.

In other words, in front of the relay lens L _4, the fork portion 3b of the pipe-like guide shaft portion 3a formed integrally with one end of the support frame 3 is formed at the other end to penetrate into one of the shaft 11a above
The lens support frame 3 is slidably disposed by fitting the lens into the other shaft 11b. A pipe-shaped guide integrally formed at one end of the support frame 2 is provided in front of the lens support frame 3. The lens support frame 2 is slidably disposed by allowing the shaft 2a to penetrate the one shaft 11a and the fork 2b formed at the other end to be fitted to the other shaft 11b. A fork 1 a formed at one end of the support frame 1 is provided between the first shaft 11 and the front fixing member 13.
The lens support frame 1 is slidably disposed by fitting a pipe-shaped guide shaft portion 1b integrally formed at the other end of the shaft into the other shaft 11b.

The lens support frames 2 and 3 are provided with guide shaft portions 2.
a and 3a have spring hooking projections 2c and 3c formed integrally with each other, and the elasticity of the contracting coil springs 14 applied to both spring hooking projections 2c and 3c gives the behavior in directions approaching each other. Have been. Further, drive pins 2d, 3d projecting laterally are formed integrally with the guide shaft portions 2a, 3a, respectively.The drive pins 2d, 3d are formed by the elasticity of contraction of the coil spring 14. It is in pressure contact with the operation cam 15a of the zoom cam 15.

The zoom cam 15 is formed of a sector-shaped cam plate, and its base is rotatably supported on the side surface of the fixed frame member 5 by mounting screws 16 and extends forward in a fan shape. An operating cam 15a formed of a partially arc-shaped ridge is formed at the distal end edge. The drive pin 2d of the support frame 2 of the variator lens L ₂ to the outer peripheral surface of the actuating cam 15a is pressed, the drive pin 3d of the support frame 3 of the compensator lens L ₃ on the inner peripheral surface is pressed against. Also, the operation cam 15a formed in a fan shape is formed such that the length in the radial direction of the upper edge (in FIG. 1) is shorter than the length of the lower edge, and a portion of the peripheral edge of the distal end is formed. the curvature of the actuating cam 15a which is formed in an arc shape is formed a variator lens L ₂ and the compensator lens L ₃ in a shape to smoothly move each zoom position. Then, the zoom cam 15 is brought driven manually or automatically during zooming, moves the lens holding frame 2 and 3 in the optical axis direction by operating cam 15a, the variator lens L ₂ and the compensator lens L ₃ each zoom position Move.

On the other hand, the fixed substrate 12 and the front fixing member 13 are overlapped with each other by fixing screws 17a to 17c which penetrate through the substrate 12 and the fixing member 13 from the front, and are formed at the corners of the front surface of the fixed frame member 5. Mounting arms extending forward from three places
They are fixed to the tip surfaces of 5b to 5d, respectively. The fixed substrate 12 has a focusing cam 18 for focusing.
Is rotatably mounted.

That is, the fixed substrate 12 is provided with an exposure opening 12a at a portion corresponding to the lens optical axis O, and a relatively thick annular ring is formed at a peripheral portion on the front side of the opening 12a. A focus cam 18 formed of a member is rotatably attached to the fixed substrate 12. The focus cam 18 is formed by the end face cam, the inclined to the optical axis direction over an angular range of approximately 90 ° to the front end surface, the focus lens L ₁ is actuated cam surface 18a for causing movement before and after the formation have been, actuating cam surface 18b to move the compensator lens L ₃ is inclined in the direction of the optical axis over an angular range of arrows tension approximately 90 ° to the rear surface in the optical axis direction are formed (see FIG. 3) .

A cam follower 20 fixed to the focus lens support frame 1 with a screw 19 and protruding rearward is provided on the working cam surface 18a having a frontal front, and a contraction is provided between the lens support frame 1 and the fixed substrate 12. The lens support frame 1 is brought into pressure contact with the substrate 12 by being attracted to the substrate 12 by a flexible coil spring 21, and the front surface of the compensator lens support frame 3 is attached to the operating cam surface 18b of the rear surface. A cam follower 22 formed of a pin formed integrally with and extending forward extends through a through hole 2 e formed in the variator lens support frame 2, and a hole provided in the fixed substrate 12.
12b is inserted and pressed.

A drive gear 18c is provided at a portion of the focus cam 18 near the fixed substrate 12, and the drive gear 18c is provided.
Was attached to the fixed substrate 12 and the front was alligated,
The rotational force of the stepping motor 23 for focusing, in which the back surface of the substrate 12 is fixed, is transmitted by a reduction gear train including a gear 24, a two-stage gear 25, and an output gear 26.

Further, the annular focus cam 18 is provided with a mechanism for detecting an initial position of the drive system. That is,
A partial arc-shaped light reflecting plate 27 is attached to a part of the outer peripheral surface of the focus cam 18, and a photo sensor 28 is provided at a predetermined position of the fixed substrate 12 so as to detect the reflected light of the light reflecting plate 27.
Are arranged.

The focus lens support frame 1 is slidably disposed in the optical axis direction in front of the fixed substrate 12 on which the focus cam 18 and the drive mechanism are mounted, and these have the exposure aperture 12a. It is covered by the front fixing member 13.

Next, the operation cam surfaces 18a and 18b of the focus cam 18 will be described in more detail with reference to FIG.
The drawing is an expanded view in which the cam surfaces 18a and 18b of the focus cam 18 are enlarged. As can be seen from this figure, an operating cam surface 18a formed of an inclined surface formed on a front end surface of an annular focus cam 18 and an operating cam surface 1 formed of an inclined surface formed on a rear end surface thereof.
8b means that the cam follower 20 performing macro focus does not abut the operating cam surface 18b while the cam follower 20 is in the normal focusing range where the cam follower 20 is pressed against the operating cam surface 18a in a normal focus operation. Also, even when the focus cam 18 is in the normal closest position (see FIG. 4B), the cam follower 22 does not abut the macro focus operation cam surface 18b.

That is, while the cam follower 20 is in the normal focusing range, the cam follower 22 is at a position opposite to the normal focus range of the flat surface 18c continuously provided in the macro focusing range, and the tip of the cam follower 22 does not contact the flat surface 18c. Even when the zoom optical system has moved to the short distance position, the tip of the cam follower 22 is still not in contact with the flat surface 18c. This is because if the cam follower 22 is designed to contact the macro focus operation cam surface 18b at the closest position during normal focus, when the focus cam 18 is set to the normal closest position due to a manufacturing error of each part, etc. Actuating cam surface 18b is cam follower 2
This is because there is a possibility that 2 may be moved.

Thus, the zoom lens drive mechanism of the camera according to the present invention is configured. Next, the operation will be described. First, at the time of normal zoom photographing, the stepping motor 23 is driven, the focus cam 18 is rotated through the gear train, and the focus lens support frame 1 is moved via the cam follower 20 by the operation cam surface 18a. by moving back and forth in the optical axis direction to move the focus lens L _1, for focusing. After focusing, the zoom cam 15 is rotated to move the variator lens support frame 2 and the compensator lens support frame 3 back and forth, so that the variator lens L ₂ ,
The compensator lens L ₃ is moved from the wide position to the wide-angle position from the telephoto position or the telephoto position to shoot it performs zooming.

Then, in the case of macro shooting, the zoom lens optical system, namely the variator lens L ₂ and the compensator lens L ₃
To the wide position. Then, the stepping motor 23 is driven to rotate the focus cam 18 so that the focus cam 18 is displaced to a position closest to the normal focus. Then, the operation cam surfaces 18a, 18b of the focus cam 18 and the cam followers 20, 22
4B, and when the focus cam 18 is further rotated by the rotation of the stepping motor 23, as shown in FIG.
cam follower 22 is pushed by b, the compensator lens support frame 3 macro focusing operation is performed by moving the compensator lens L ₃ and retreat. Also, during this macro focus, a cam follower for normal focus is used.
20 so pressed against the flat surface 18d of the front end surface of extruded from actuating cam surface 18a the cam 18, the focus lens L ₁ is maintained at a fixed position of the closest.

After the macro focus operation is performed in this way and the subject is focused, macro shooting is performed.

Therefore, in the zoom mechanism of the present invention, it is possible to perform macro-focusing using a normal focusing member, and if the zoom is in a wide state, the focusing operation can be performed without any switching operation. .

In addition, this configuration has an advantage that the adjustment of the lens system can be easily performed.

That is, since the image forming position is not exactly at the predetermined image forming position when the lens is simply assembled, it is necessary to adjust the image forming position.
In the case of the configuration of the lens group, relative to the normal focus, 2 and adjustment of the focus lens L ₁ and the variator lens L ₂ distance, the back focus adjustment (adjusting the gap relay lens L ₄ and the image pickup device) Done for points.

Interval adjustment The adjustment of L ₁ and L ₂ are simply just a state assembling the lens focusing position is moved when performing the zooming operation, as shown in FIG. 5 (B) from FIG. 5 (A) since phenomenon to cause occurs because of errors in the thickness or distance between lens elements of the lens to adjust the position of the focus lens L ₁ as an image forming position while checking by some means the imaging position does not move by zooming.

The adjustment between the optical reference position of the focus lens and the initial position of the drive system is generally called, for example, infinite position adjustment. In the present invention, a margin is provided at both ends of the focus cam 18 and the focus cam is rotated. Adjust. That is, to detect the initial position of the focus cam in the photo sensor 28, is adjusted by the cam to the reference position of the focus lens L ₁ does not occur with optically focus shift. Then, the initial position and the lens L ₁ of the focus cam to store the difference between the focus cam position at which said position.

After adjusting the back focus adjustment above, to adjust the position or the position of the imaging element itself of the relay lens L ₄ while monitoring the signal from the image pickup device.

The adjustment of the two points is performed in this manner. However, in the macro focus using the focusing cam as in the present invention, the initial position for driving the focusing cam, the distance between the initial position and the object distance, and the compensator lens L for this macro are used. _It is necessary to match the positional relationship with ₃ . Therefore,
The following adjustments need to be made.

This adjustment is necessary because the focus cam is usually driven to the macro side beyond the closest position, and it is necessary to know the rotation position of the focus cam 18 at which the macro operation cam surface 18b starts moving the cam follower 22. This position is used as a reference when focusing with a macro. This position is stored in the AF drive control system as a difference from the initial position when the focus cam is driven. That is, the number of steps for moving the focus cam from the initial driving position to the macro reference position is stored using the stepping motor 23 for AF driving.

Next, an example of the adjustment procedure described above will be described with reference to FIGS. FIG. 6 is a block diagram showing a configuration necessary for the adjustment procedure in the camera of the present invention, and FIG.
FIG. 8 is a diagram showing the relationship between the rotational position of the focusing cam and the initial position sensor in accordance with the number of steps of the stepping motor. FIG. 8 is a flowchart of the adjustment sequence.

As shown in FIG. 6, the configuration necessary for the adjustment includes a distance measuring sensor 30 for measuring the distance to the subject and the photo reflector 28 for detecting the turning position of the focus cam 18 by the reflecting plate 27. An initial position sensor, a microcomputer 31 to which outputs of both sensors are input, and a microcomputer
A motor drive circuit 32 whose operation is controlled by the motor 31; the stepping motor 23 driven to rotate by the drive circuit 32; the focus cam 18 rotated by the motor; and an electrically writable / erasable E ² PROM 33. It is composed of

The E ² PROM 33 is used to store the relationship between the initial position required for driving, the actual reference position of the normal focus area, and the reference position of the macro area. The microcomputer 31 also controls the rotation amount of the motor 23 based on the output of the distance measurement sensor 30.

With such a configuration, adjustment is performed as shown in FIGS. As shown in FIG. 7, each step of the stepping motor 23 corresponds to the rotation angle of the focus cam 18 on a 1: 1 basis. And in this example, A _{0 in} FIG.
Each position indicated by to D ₀ is intended to mean each the next position. A ₀ : the position detected by the initial position sensor 28 (the initial position for driving the focus cam) B ₀ : the reference position of the normal focus area (∞) C ₀ : the reference position of the macro area D ₀ : the maximum position of the normal focus area It is the closest position. In this example, first, a procedure for detecting the reference position of the macro area and then detecting the reference position of the normal focus area will be described. Needless to say, the detection order may be A ₀ −B ₀ −C _0. .

As shown in the flow of FIG. 8, adjustment of the, first focus lens L ₁ reference position B _0, i.e. it is moved by driving the cam 18 to the optical reference position. Then, 0 is substituted for STEP. The variable STEP represents the step corresponding to the actual position of the focus cam, that is, the number of steps corresponding to the current position of the cam. Thus, the infinite position B ₀
Is detected, and then the macro reference position _C0 is detected. This is +
It drives one step at a time, substitutes STEP + 1 for STEP, and detects step by step. Then, it is checked whether the macro reference position, further continued detection of one step if "N", if "Y" STEP number C ₀ is substituted. For example, when it reaches the 63 steps as shown in FIG. 7, when it is detected as a reference position, it is substituted for the 63 as C _0.

Next, detection of the detection position by the initial position sensor 28 is performed. This checks whether the sensor is ON or OFF,
If “Y”, it is driven by -1 step at a time, and
-1 is substituted. Then, as shown in FIG. 7, for example, at step 55, the sensor is turned off. This is checked by sensor ON? And detected again. “N” for this check
If so, it has gone too far in the negative direction, so that +1 step drive is performed, and STEP + 1 is substituted for STEP. Then, a sensor check is performed again. If "N", the +1 step driving is further continued.
The STEP is assigned as A _0. Then, the A ₀ and the C ₀ E ²
The adjustment is completed by writing to the PROM 33 (see FIG. 6).

The above is the adjustment operation. This adjustment operation is performed before shipment of the camera.

Next, the AF operation of the camera adjusted as described above will be described with reference to FIGS. 9 and 10. Since the camera is normally in a power-off (power-off) state, the microcomputer 31 cannot determine the position of the lens. I don't know because I don't remember. Therefore, first, the lens reset operation is performed when the power is turned on.

Operation of the lens reset, either the sensor 28 falls anywhere in position, i.e., performed in operation to detect the initial position A _0.

FIG. 9A shows an example of this. In this lens reset flow, it is first determined whether or not the sensor 28 is ON. If the sensor is in the ON state at "Y" in this check, how much the detection position has gone too far is driven by -1 step, and the sensor ON? Is checked again. Also in this case, if "Y", the -1 step drive is continued until the sensor ON? Becomes "N". If it is "N", it is checked how much it goes to the negative side by performing +1 step driving. Next, the sensor ON? Check is performed again.
One-step driving is continued, and if "Y", the initial position _A0 is detected here. Lens reset operation by substituting the initial position A ₀ in STEP variable representing the current position of the lens is completed.

In the example of FIG. 9A, the reset position is A ₀ STEP. However, when the reset position is 0 step, the example shown in FIG. 9B may be used. . That is, this flow of FIG. 9 (B), although the operation until assigned to STEP detects the initial position A ₀ is performed exactly as in the example of the FIG. 9 (A), Thereafter, The difference is that the number of steps is returned to 0 by performing -A ₀ step drive, and 0 is substituted for STEP.

This lens reset operation is not limited to the two examples shown in FIGS. 9 (A) and 9 (B), but may be any other appropriate steps. For example, the number of steps can be set at a position with a high probability, such as 1 m or 2 m, which is frequently used for the subject distance.

After ending the lens reset operation in this manner, the tenth
Enter the AF operation shown in the figure. In this AF operation, first, a distance measurement operation is performed by a distance measurement IC having the distance measurement sensor 30 (see FIG. 6) to measure the distance to the subject. Next, it is determined whether or not the measured distance is a macro area. If the measured distance is “N”, the drive amount N is calculated from the 0 step of the reference position B _{0 because} the area is a normal focus area. . Note that the value of N is obtained by using a predetermined conversion table based on the measured distance. Next, processing of a drive amount calculation N-STEP from the current position is performed. That is, the difference between the drive amount N from the 0 step and the current position, such as the number of steps the current lens is located at, that is, the position of a variable called STEP, and the number of steps to be driven from the current position. -STEP calculation is performed. Then, driving is performed by the driving amount calculated by this calculation. Next, N is substituted for the STEP variable, and the AF operation ends.

If the macro area check shows "Y", the distance measurement range is the macro area, so the reference position C _{0 of the} macro area.
Is calculated from the driving amount M. Note that the value of M is obtained by using a predetermined conversion table based on the measured distance measured by the distance measuring operation. Then the reference position C ₀ is read from the E ² PROM33 (see Figure 6). Then, calculation of the driving amount from the position B _0,
That is, M + C ₀ is performed, and then a drive amount calculation process from the current position, that is, (M + C ₀ ) -STEP is performed.
It is driven by the drive amount. Then, (M +
C ₀ ) is substituted and the AF operation ends.

Since the AF operation in the camera of the present invention is performed in this manner, there is an advantage that if the zoom is kept in a wide state, a switching operation between the normal focus and the macro focus is not required, and a fine focus operation can be performed.

According to the present embodiment, the difference between the reference position, which is the position of the cam where the focus cam is infinite, and the initial position of the cam detected by the position detection sensor is stored in the lens unit or the camera, and based on this value, Find the current position of the camera's taking lens. If the measurement result of the distance to the subject corresponds to a normal measurement result, the photographing lens is driven based on the measurement result of the distance to the subject and the current position of the photographing lens, and the measurement result of the distance to the subject is obtained. If it corresponds to the macro area, it is extremely necessary to drive the taking lens based on the driving amount from the reference position of the macro area and the driving amount from the current position of the taking lens to the reference position of the macro area. The effect that simple AF operation can be performed is obtained.

In the adjustment of the infinity of the focus lens and the position of the macro AF cam and the compensator lens before shipment of the camera, manual adjustment of mechanical parts was abolished to eliminate uncertain errors caused by adjustment, and assembly adjustment Man-hours can be reduced.

In particular, when using an external light type, that is, an AF drive system with open control using a distance measurement method other than TTL, and driving a normal focus macro with open control, it is extremely important to bring the lens to their optical reference position. But
If this embodiment is applied, since there is no specific mechanical adjustment, it is possible to perform very convenient, simple, and accurate reference positioning of the optical system.

As described above, according to the present embodiment, conventional effects can be eliminated, and various effects can be exhibited.

[Effects of the Invention] As described above, according to the present invention, mechanical position adjustment of the photographing lens becomes extremely simple, and macro photography and normal photography can be switched very easily, so that macro photography or normal photography can be performed. There is a remarkable effect that the photographing lens can be accurately positioned at a predetermined position in accordance with the condition.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a zoom and AF mechanism in a camera showing one embodiment of the present invention, FIG. 2 is a cross-sectional view of the zoom and AF mechanism of FIG. 1, and FIG. 4 (A) to 4 (C) are main part enlarged development views each showing the operation of the focus cam, and FIG. 5 is a diagram showing the operation of a four-group zoom lens. FIG. 6 is a block diagram showing the configuration of each part necessary for adjustment in the camera of the present invention. FIG. 7 shows the relationship between the rotational position of the focus cam and the initial position sensor corresponding to the number of steps of the stepping motor. FIG. 8 is a flowchart of an adjustment sequence, FIGS. 9A and 9B are flowcharts respectively showing an example of a lens reset operation, FIG. 10 is a flowchart of an AF operation sequence, FIG. Figure 11 shows 4 groups Diagram for explaining the zooming operation and macro focusing operation of the configuration of the zoom lens, Fig. 12 is a fragmentary plan view of a zoom sleeve of an example of a conventional zoom mechanism and macro focusing mechanism. L ₁ … Focus lens L ₂ … Variator lens L ₃ … Compensator lens L ₄ … Relay lens 18… Focus cam (single operating member) 18 a… Normal focus operation cam surface 18 b… Macro focus Working cam surface

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02B 7/08 G02B 7/105

Claims (1)

(57) [Scope of request for utility model registration] 1. A means for detecting a preset initial position of a photographing lens when power is turned on; a means for storing a preset reference position of a macro area of the photographing lens; Means for detecting the current position of the taking lens, means for measuring the distance to the subject, and means for driving the taking lens, based on the result of the measurement of the distance to the subject corresponding to the macro area. If so, the photographing lens is driven based on the driving amount from the reference position of the macro area and the driving amount from the current position of the photographing lens to the reference position of the macro area, and the measurement result of the distance to the subject is obtained. A photographing lens device that drives the photographing lens based on a driving amount of the photographing lens from a current position if the photographing lens corresponds to a normal focus area.