JP3001202B2 - Variable focal length camera - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a camera, and more particularly to a variable focal length camera having a zoom function.

(Prior Art) A camera having an integrated zoom lens has been developed. For example, JP-A-62-111611 and JP-A-61-2602
No. 10 discloses a fixed lens body camera with a fixed zoom lens.

(Problems to be Solved by the Invention) A major drawback of the fixed-lens-type lens body camera is its size. In particular, the length in the optical axis direction is almost determined by the overall length of the lens system. However, if a single lens is used to obtain a large zoom ratio, the amount of movement of the lens group increases, and the difficulty of aberration correction increases. The number of lenses increases, and the lens system becomes longer. For this reason, it is difficult to reduce the size of the camera body. With a lens having a zoom ratio of about 2 times, a small and inexpensive camera with a small moving amount and about 6 to 8 components can be realized by a so-called two-unit zoom having two moving lens units. For example, JP-A-62-111611
In the official gazette, a total length of 100 m with a zoom of approximately 2 times the focal length of 36 to 67
A camera having a seven-lens configuration around m is shown. However, when the zoom ratio is further increased in the two-unit zoom, the amount of movement of each unit increases, and the diameter of the front lens increases.
For this reason, if the zoom ratio is 3 to 4 times or more, the number of components of the zoom lens of the third group zoom or more is considerably increased to about 12 to 16 elements. In the camera of Japanese Patent Application Laid-Open No. 61-260210, the focal length is approximately 3.6 times that of 36 to 130 and the total length is 14
Around 0mm, the configuration is 15 sheets, which is quite large.

Accordingly, an object of the present invention is to provide a small and substantially high-magnification camera with a built-in zoom lens by combining a low-magnification zoom and a teleconverter.

(Means and Action for Solving the Problems) According to the present invention, since the zoom lens optical system and the focal length of the zoom lens optical system are changed to the telephoto side, the zoom lens optical system can be moved at a magnification equal to the zoom ratio of the zoom lens optical system. A teleconverter, an insertion / removal mechanism for inserting and removing the teleconverter into and from the optical path of the zoom lens optical system, and moving the zoom lens optical system in the direction of its optical axis to change the focal length of the zoom lens optical system. A first drive unit that obtains a focal length from wide angle to telephoto only with the zoom lens optical system, and a zoom lens optical system that is different from the focal length from wide angle to telephoto in order to obtain a more telephoto focal length range has an optical axis. A second driving unit that moves in the direction, and a first driving unit and a second driving unit that are formed between the first driving unit and the second driving unit to form a zoom lens Light optics A third drive unit for moving the teleconverter in the optical path of the zoom lens optical system while moving the teleconverter in the axial direction and operating the insertion / removal mechanism, and a second drive unit from the first drive unit When the zoom lens optical system is driven, the teleconverter is inserted into the optical path of the zoom lens optical system by operating the insertion / removal mechanism in the third driving unit, and telephoto is continuously performed from the telephoto end obtained by the first driving unit. A variable focal length camera characterized in that the focal length of the zoom lens can be changed to the side.

(Embodiment) FIG. 1 shows a focal length when the zoom ratio and the magnification of the teleconverter are matched according to the present invention. In the same figure, A is a 1.7x zoom, focal length 35-61m
When a 1.7x teleconverter is inserted into the m zoom lens, 35-
It becomes a 3x zoom of 105mm. In the case of B, when a 2x teleconverter is inserted into a zoom lens having a 2x zoom and a focal length of 35 to 70 mm, a 4x zoom of 35 to 14 mm can be obtained.

FIG. 2 shows the amount of movement of the lens in A of FIG. According to this, when the teleconverter enters when the focal length is 61 mm, the zoom lens unit located on the telephoto side is displaced to the wide side at the same time as providing the focal length of 61 mm with the zoom lens and the teleconverter. I understand.

Next, a specific embodiment of the present invention will be described with reference to FIG.

According to FIG. 3, the lens barrel of the camera includes a cam can 1, a teleconverter 2, a seppen 3, an encoder 4, a fixed frame 5, and a zoom lens 9. Kamcan 1 is 1
It has cam grooves (1a, 1b) for performing the zoom operation of each lens group of the first and second groups, and is rotated with respect to the optical axis by a zoom motor (not shown), and the zoom ratio is 1.7 times . The cam grooves (1a, 1b) are arranged so as to perform the zoom operation shown in FIG. In addition, the end face 1c for teleconverter switching
Is provided for insertion and removal of the teleconverter 2, and this end face is configured to abut on the lens frame of the teleconverter 2 during zooming and push up the teleconverter.

The teleconverter 2 is a teleconverter for shifting the focal length to the telephoto side, that is, the telephoto side.
It is rotatable about the teleconverter rotation center shaft 2a by a factor of 1.7, and is urged clockwise by a teleconverter advance / retreat spring 8.

In FIG. 3, when the roller 6 on the lens frame is in the storage start position, the seppen 3a, 3b, 3c are turned on, and when the roller 6 is in the range of θ1, the seppen 3b, 3c are turned on, and the roller 6 is turned on. When in the range of θ3, 3a and 3b are turned ON.

The fixed frame 5 has a zoom lens group with rollers 6 on the lens frame,
It is provided to restrict the moving direction to the optical axis direction when driven by the cam can 7 and the cam can. The teleconverter locking end face 5b shown in FIG. 5 is provided for position determination when the teleconverter enters.

The zoom lens is a two-unit zoom lens having a lens diameter of 35 to 61 mm and a zoom ratio of 1.7 times.

 Next, the operation of the lens barrel will be described.

The positional relationship between the zoom lens (each group) and the teleconverter at the time of "storage" shown in FIG. 2 corresponds to the case where the storage start position 1d of the cam can 1 is on the rectilinear groove 5a on the fixed frame in FIG. . Power switch not shown or
When the cam can 1 is turned counterclockwise by the storage-photographing change-over switch and the zoom motor, one group, 2
The rollers 6, 7 on the lens frame of the group are cam grooves 1a,
When the lens moves along 1b and the rotation angle becomes θ1, each of the first and second lens units forms a lens with f = 35 mm.

When the cam can is moving in the range from (0) to (θ1) when the lens is retracted, the seppen 3a and 3b are turned on by the encoder 4a, and the release operation in this range is disabled by the circuit described later and the power switch is turned off. The zoom motor is rotated by ON / OFF or ON / OFF of the storage / photographing changeover switch, and the cam can 1 is rotated to either (0) or (θ1) so as not to stop halfway. .

Further, while the cam can 1 rotates counterclockwise by θ2, the focal length changes from 35 mm to 61 mm, and the rotation angle becomes θ1 + θ2.
At this point, f = 61 mm.

The movement of the teleconverter 2 when the cam can 1 is rotating in the range of θ3 will be described with reference to FIGS. 5a, 5b and 5c.

The position where the cam can 1 is rotated clockwise by θ1 + θ2 from the storage position is shown in FIG. 5a. The teleconverter 2 is pushed up by the switching end face 1c of the cam can 1,
The spring 8 urges the switching end face. In addition, 5a
FIG. 5 to FIG. 5a are views seen from the back of the optical axis, that is, from the film surface.

When the cam can 1 further rotates, the switching end face 1c comes off the teleconverter 2, and as shown in FIG. 5b, the teleconverter 2 rotates counterclockwise about the rotation shaft 2a and enters the optical axis. When the rotation angle of the cam can 1 becomes θ1 + θ2 + θ3, the teleconverter switching end face 1c of the cam can 1 is disengaged from the teleconverter 2, and the teleconverter 2 comes into contact with the teleconverter locking end face 5b of the fixed frame 5 and completely enters the optical axis. (Fig. 5c).

When the cam can 1 is moving in the range of θ3, the zoom lens groups (the first and second groups) are moved by the cam grooves 1a and 2a. After the θ3 rotation is completed, the zoom lens group is in wide (wide angle) (f = 35 mm). The wide-lens system has a teleconverter 2
Is inserted, f = 35 × 1.7 = 61 mm, which is almost the same as the focal length before the cam can 1 rotates θ3.

When Cam Can 1 is in the range of θ3, Seppen 3
b, 3c are turned on by the encoder 4b, and even if the zoom operation is stopped halfway by the circuit described later, the zoom motor does not stop, and the teleconverter 2 completely enters the optical path,
After the seppen 3c and 3b are turned off, that is, the rotation angle is θ1 + θ
It stops when it becomes 2 + θ3. Similarly, when the seppens 3b and 3c are turned on by a circuit described later, the release is not operated.

When the zoom operation is further performed after the teleconverter 2 is inserted, the cam lens 1 drives the first and second zoom lenses in the range of θ4, and the zoom lens unit has f = 35 to 61 mm.
Is f = 61 to 105 mm because the teleconverter 2 has entered.

The cam can 1 is moved from the storage position to θ1 + θ2 + θ3 + θ4.
The position rotated by only f = 105 mm is the tele (telephoto) end. The development of the lens frame shown in FIG. 4 shows a lens configuration with f = 105 mm. The teleconverter 2 is not shown in the figure.

When the photographing is completed, by turning off the power switch or the storage-photographing changeover switch, the zoom motor is rotated in the W direction by the circuit described later, and the cam can 1 shown in FIG. 3 starts to rotate clockwise. When all of the pens 3a, 3b, 3c are turned on by the encoder 4a, the drive circuit 18 stops the motor.

Next, a driving circuit of the zoom motor will be described with reference to FIG.

The zoom operation switch SW1 can be switched between the TELE (telephoto) direction and the WIDE (wide angle) direction, and is normally in the neutral position, and is turned ON only when operated. Switch SW2 is set to Seppen 3 in FIG.
This is a switch composed of b and 3c. The switch SW3 is a switch composed of the pens 3a and 3b in FIG. The switch SW4 is a release switch. The switch SW5 is connected to a power switch (not shown) and connected to N
O, OFF switch or storage-photographing changeover switch.

When the outputs of the OR gates OR1 and OR2 become "H", the motor driver 18 moves the zoom motor 10 in the T direction and the W direction, respectively.
Drive.

First, assume that the lens is in the retracted state in FIG. At this time, since the slices 3a, 3b, and 3c are all turned on by the encoder 4a, the NAND gate NA1 outputs “L”, and therefore, regardless of whether the switch SW5 is on or off, the NAND gate NA1 is turned on.
3 outputs "H" and does not rotate the motor 10 in the W direction.

On the other hand, since the switch SW2 (3b, 3c) is ON, the NAND
The input to the gate NA2 becomes “H”, and the other input becomes “H” when the power switch SW5 is turned on, and the NAND gate N2
The output of A2 is "L" and the output of OR gate OR1 is "H". Therefore, the motor driver 18 rotates the zoom motor 10 in the T direction. When the cam can 1 rotates θ1 in FIG. 3, the switch SW3 (3a, 3b) is turned off. By this NAN
One of the inputs of the D gate NA2 becomes “L”, and the motor stops at the output “L” of the OR gate OR1. The above operation has been described until the zoom motor 10 moves to the photographable state (f = 35 mm) when the power switch is turned on when the lens is stored.

Next, even if the zoom switch SW1 is operated in the W direction,
Since the set-reset flip-flop SRFF1 is reset, the output of the AND gate AND1 is always "L", so the NAND gate NA7 outputs "H", the output of the OR gate OR2 is "L", and the motor 10 does not rotate. . This is currently f = 35mm
Because the camera is at the wide end, it cannot move further in the wide direction.

Next, when the zoom switch SW1 is operated in the T direction, N
The input of AND gate NA6 is “H”, and the other input is AND1 =
Since "L" and inverter INV2 = "H", the output of the NAND gate NA6 becomes "L", the output of OR1 is "H", and the motor driver 18 rotates the motor 10 in the T direction. Switch SW1
Is turned off, the motor 10 stops.

Once the zoom switch SW1 is operated in the T direction, the SRF
F1 is set and the output Q becomes "H". Therefore, the output of AND1 becomes "H" when the W direction of the switch SW1 is ON, and becomes "L" when it is OFF, and the motor 10 can be driven in the W direction via the NA7 and OR2. When the switch reaches the W end, the switch SW3 (3a, 3b)
Since it is turned on, SRFF1 is reset, and the W direction of the switch SW1 does not function as in the above-described state.

By operating the switch SW1 in the T direction, the switch SW2 (3b, 3b,
When 3c) turns ON, the input of the NAND gate NA4 becomes “H”.
On the other hand, SRFF2 is set because the switch SW1 has been operated in the T direction until then, and since Q = “H”,
The input to the second NAND gate NA4 also becomes "H". Also, N
Since the switch SW1 of the AND gate NA7 is operated in the T direction, the output of the inverter INV1 is “L” and the NAND gate
The output of NA7 becomes "H" and the output of NAND gate NA4 becomes "L". Accordingly, the output of the OR gate OR1 becomes "H", and the zoom motor 10 moves in the T direction.

Since the output of the NAND gate NA7 is "H" even when the switch SW1 is in the neutral state, the motor 10 continues to move in the T direction.
During this time, the teleconverter 2 enters on the optical axis. When the entry of the teleconverter 2 is completed, the switch SW2 (3b,
3c) turns off and the input of the NAND gate NA4 becomes “L”, so that NA
The output of the ND gate NA4 becomes "H", the output of the OR gate OR1 becomes "L", and the motor stops.

On the other hand, when the motor is rotated in the W direction by the operation of SW1 in the W direction, SW2 is retracted to retract the teleconverter 2.
When (3b, 3c) is turned ON, the input of NA5 becomes “H” and SRFF
Since 2 has been reset by the W direction operation, Q =
When “H”, the second input of the NAND gate NA5 is also “H” and NAN
Since the output of the D gate NA6 is "H" unless SW1 is turned ON in the T direction, the output of the NAND gate NA5 is "L" and the output of OR2 is "H", and the motor rotates in the W direction. If the teleconverter is retracted and switches SW2 (3B, 3C) are turned off, one of the inputs of NA5 becomes "L" and the motor stops. Also, SW2
When SW1 is operated in the T direction while (3b, 3c) is ON, SRFF2 is set and NA5 = "H", and conversely NA4 = "L". Therefore, OR1 = "H" and OR2 = "L", and the motor switches its operation from the W direction to the T direction.

As described above, while the switch SW2 (3b, 3c) is ON (when the teleconverter is inserted or removed), even if the zoom operation of the switch SW1 is interrupted, the switch SW2 is turned off, that is, the insertion and removal of the teleconverter 2 is completed. Until the motor does not stop. However, it is possible to switch the direction of the operation during the operation.

When the power switch is turned off after shooting is completed, switch SW5 is turned off.
Then, the input of the NAND gate NA3 becomes “H”, and the other input is also connected to the switches SW2 (3b, 3c) and the switch SW3 (3a, 3b).
Unless one is ON, the output of the NAND gate NA1 is "H", the output of the NAND gate NA3 is "L", the output of the OR gate OR2 is "H", and the motor rotates in the W direction. When the cam can 1 in FIG. 3 rotates to the lens storage position, the switches SW2 (3b, 3c) and the switch SW3 (3a, 3b)
Turns on, the output of NAND gate NA1 is "L", and NAND gate NA3
Is "H", the output of OR gate OR2 is "L", and the motor stops.

On the other hand, for the release, when the switch SW2 (3b, 3c) or the switch SW3 (3a, 3b) is ON, that is, between the time of storage and the wide end f = 35 mm and the time of insertion / removal of the teleconverter, the OR gate OR3 Either of the inputs to “1” becomes “H”, and the output of the OR gate OR3 becomes “L”. Therefore, the output of AND2 is always “L”. Therefore, even if the release switch SW4 is operated, no signal is transmitted to the release processing circuit, and the release is not operated. This is a fail-safe mechanism for preventing a useless photograph from being taken when the lens system is not in a photographable state.

FIG. 7 shows a lens frame portion according to the control method of the second embodiment, which is different from the first embodiment. The encoder 4 includes a zoom encoder unit that detects a movement amount of a focal length and a lens status unit that indicates a state of a lens configuration. The seppen 3 is connected to a CPU (not shown), and transmits information from the encoder 4 to the CPU.

FIG. 8 shows an enlarged form of this part, which is combined with the system. The zoom encoder section is θ0
It is divided into six regions of θ5, each of which is described below.

θ0 Lens retracted state θ1 Lens retracted, photographable area switching state (impossible to be photographed) θ2 f = 35 to 61 mm photographable state θ3 Teleconverter converter in the middle of insertion / removal (photographable) θ4 f = 61 to 105 mm photographable state θ5 f = 105mm tele end Seppen 3a to 3e are members that detect each state, seppen 3a is GND common, seppen 3c to 3e are 6
For state detection, the seppen 3b functions as a zoom encoder.

The CPU reads the states of these switches, and drives the zoom motor 10 in accordance with the ON / OFF state of the zoom switch SW13 (ON or OFF in either the T direction or the W direction) and the power switch SW14.

Since the other mechanical configuration is the same as that of the first embodiment, the description will be omitted, and the operation will be described with reference to FIG.

First, when the power switch SW14 is turned on when the lens is in the housed state (θ0), an interrupt is generated in the CPU, and the flow enters FIG. 9A. Here, since the power switch SW14 is in the ON state in the θ1 region, the flow proceeds to the flow below and the motor 10 is rotated in the T direction. The motor 10 is stopped when the vehicle exits the θ1 region and enters the θ2 region.

Then, by zoom operation, the zoom switch SW13
When turned on, the flow enters the flow shown in FIG. 9 (b). When there is a lens in the θ5 region, the motor 10 is turned off because the motor 10 cannot be further driven to the telephoto side, but in the region of θ2 to θ4, the motor 10 is driven in the T direction. If there is a lens in the θ3 area, the interrupt by the release is prohibited,
The motor continues to be driven in the T direction until the area is cleared. When the .theta.3 area is cleared, release is possible, and the drive and stop of the motor are determined by whether or not the switch SW13 is turned on in the T direction.

When the switch SW13 is operated in the W direction, it is determined whether or not it is in the θ1 region. If it is in the θ1 region, the motor 10 is turned off. Otherwise, the motor 10 is driven in the W direction. If there is a lens in the θ3 region, the motor 10 continues to be driven in the W direction until the lens is out of the θ3 region in the same manner as the T-direction operation described above. During this time, the release is prohibited.

When the power switch SW14 is turned off after shooting,
The flow shown in FIG. Since the power switch SW is OFF, proceed to the lower part of FIG. 9 (a) in the first branch. If the area is not in the θ0 area, the motor 10 is driven in the W direction. Stored state.

During zoom operation, count of encoder output, etc.
Other operations must be performed, but for simplicity
It is omitted in the figure.

(Effect of the Invention) Using a zoom lens and a detachable teleconverter together,
Since the focal length of the zoom lens can be continuously changed from the telephoto end obtained by the single zoom lens to the further telephoto side, a zoom lens with substantially high magnification can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a relationship between a zoom ratio and a magnification value of a teleconverter set according to the present invention and a focal length;
FIG. 2 is a diagram showing the relationship between the movement of the zoom lens and the focal length, FIG. 3 is a perspective view of the mirror copper of the variable focal length camera according to one embodiment of the present invention, and FIG. 5a to 5c are views showing the inserted state of the teleconverter, FIG. 6 is a circuit diagram of a zoom motor drive circuit,
FIG. 7 is an exploded perspective view of a mirror copper of a camera according to another embodiment, FIG. 8 is a schematic configuration diagram of a main part of the embodiment of FIG. 7, and FIG. 9 is an operation of the embodiment of FIG. The flowchart explaining
It is a figure showing a, b, and c. 1 ... zoom lens, 2 ... teleconverter, 3a, 3b,
3c …… Sepen, 4 …… Encoder, 5 …… Fixed frame,
6, 7 ... lens frame roller, 9 ... zoom lens, 10 ...
... Zoom motor, 18 ... Motor driver.

Continuation of the front page (72) Inventor Kazuo Inari 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (56) References JP-A-63-55509 (JP, A)

Claims (2)

(57) [Claims] 1. A zoom lens optical system, a movable teleconverter having a magnification equal to a zoom ratio of the zoom lens optical system for changing a focal length of the zoom lens optical system to a telephoto side, and the teleconverter. And an insertion / removal mechanism for inserting and detaching the zoom lens optical system into and from the optical path of the zoom lens optical system, and moving the zoom lens optical system in the optical axis direction to change the focal length of the zoom lens optical system. A first drive unit that obtains a focal length from wide angle to telephoto only with the system, and a zoom lens optical system which is different from the focal length from wide angle to telephoto in the optical axis direction in order to obtain a more telephoto focal length range. A second driving unit that moves the first driving unit and the second driving unit, and the first driving unit and the second driving unit are continuously formed. The said A third drive unit that moves the zoom lens optical system in the direction of the optical axis, activates the insertion / removal mechanism, and inserts / removes the teleconverter into / from the optical path of the zoom lens optical system; When the zoom lens optical system is driven from the drive unit to the second drive unit, the insertion / removal mechanism is operated in the third drive unit to insert the teleconverter into the optical path of the zoom lens optical system. A variable focal length camera wherein the focal length of the zoom lens can be continuously changed from the telephoto end obtained by the first drive unit to the telephoto side. 2. The apparatus according to claim 1, wherein said first, second and third drive units are constituted by cam mechanisms.
The variable focal length camera according to the above.