JP3976870B2 - Optical equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an optical apparatus such as a camera provided with a finder optical system capable of zooming operation (zooming) in conjunction with a photographing optical system.
[0002]
[Prior art]
Conventionally, the zoom operation of the zoom finder is driven in conjunction with the focal length switching (zoom) operation of the photographing optical system. At that time, the interlocking mechanism is configured so that the field of view of the finder becomes an appropriate value.
[0003]
In recent years, in order to reduce the size and cost of cameras, there are an increasing number of cameras in which a zoom mechanism and a focusing mechanism of a photographing optical system are integrated. Even in such a camera, the finder optical system is linked to the photographic optical system to perform the zoom operation of the finder. However, if the finder optical system is always linked, the finder optical system moves during the focusing operation of the photographic optical system, and the finder optical system is looked into. May cause the photographer to feel uncomfortable.
[0004]
Japanese Patent Application Laid-Open No. 9-2111554 proposes a camera in which the finder optical system and the photographing optical system are interlocked during zooming and are not interlocked during focusing. At that time, the field of view is set by the position once extended to a position exceeding the focus area of the zoom position where the photographing optical system is stopped by the sequence of the zoom operation.
[0005]
[Problems to be solved by the invention]
However, in the camera proposed in Japanese Patent Laid-Open No. 9-2111554, the viewfinder field ratio is adjusted to an appropriate value by the zoom operation sequence in the tele direction, so the zoom mechanism and the focus mechanism are not used during the zoom operation in the wide direction. There has been a problem that the field-of-view rate is shifted due to the manufacturing error of the mechanism due to the complication of the cam due to the integration, and the sensitivity of the finder optical system at the higher magnification of the zoom.
[0006]
Therefore, an object of the present invention is to provide an optical apparatus that can appropriately set the field of view of the zoom finder regardless of the zooming direction at the zoom stop position.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, in the present invention, a photographic optical system, a cam means for driving the photographic optical system, and a finder optical that is linked to the zooming drive of the photographic optical system by the cam means and is not linked to the focusing drive. In the optical apparatus having the system and the control means for controlling the drive of the cam means , the cam means includes a focusing drive region used for focusing drive of the photographing optical system, and zooming of the photographing optical system on both sides of the focusing drive region. A zooming drive area used for driving, and the control means moves the imaging optical system from the focusing drive area of the cam means to the zooming drive area at the zoom stop position when zooming in the tele and wide directions. There line position adjustment of the finder optical system, to the control unit, the telephoto direction First movement amount and sets each second movement amount from the focusing drive area of the photographing optical system to the zooming driving area during zooming to the wide direction from the focusing drive region of the photographing optical system during zooming to zooming drive region I try to let them.
[0008]
Since the visual field rate of the finder optical system is determined by the first and second moving amount, by adopting the configuration described above, the first and second movement amount becomes proper field ratio of the finder for each zooming direction By storing and holding in a storage means such as an EEPROM, the viewfinder field ratio at the zoom stop position can be set appropriately regardless of the zooming direction.
[0009]
When there are a plurality of zoom stop positions, the first and second movement amounts for each zooming direction are set for each zoom stop position, so that all zoom stop positions have zooming directions. However, it is desirable to be able to set the viewfinder field ratio appropriately.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
(First embodiment)
FIG. 1 shows a zoom lens barrel of a photographing optical system of a camera which is a first embodiment of the present invention. A fixed female helicoid cylinder 1 having a female helicoid 1a on the inner periphery of the cylinder and a fixing flange portion 1b on the outer periphery has a hole 1c at the center of the side surface. Further, the inner periphery has a plurality of key grooves 1d.
[0011]
The male helicoid cylinder 2 having a male female helicoid 2a that fits with the fixed female helicoid cylinder 1 has a spiral gear 2b along the male helicoid lead. The spiral gear 2b meshes with the drive gear 3 protruding to the inside of the fixed female helicoid cylinder 1 through the hole 1c when the fixed female helicoid cylinder 1 and the male helicoid cylinder 2 are in a helicoid fit.
[0012]
With the above configuration, when the drive gear 3 rotates, the male helicoid cylinder 2 extends in the optical axis direction with respect to the fixed female helicoid cylinder 1 while rotating. In addition, a rectilinear cylinder 4 that is rotatably fitted to the male helicoid cylinder 2 and fixed so as not to come out in the optical axis direction is accommodated in the inner periphery of the male helicoid cylinder 2.
[0013]
A plurality of keys 4 a that are fitted and slid in the key grooves 1 d of the fixed female helicoid cylinder 1 are formed at the end of the rectilinear cylinder 4. Accordingly, when the male helicoid cylinder 2 is rotated and fed out with respect to the fixed female helicoid cylinder 1, the rectilinear cylinder 4 does not rotate integrally with the male helicoid cylinder 2, and the optical axis direction is relative to the fixed female helicoid cylinder 1. To go out.
[0014]
Further, the inner periphery of the rectilinear cylinder 4 accommodates lens frames 5 and 6 that hold a lens group (not shown), a shutter opening / closing mechanism, a focusing lens extension mechanism, and the like. A plurality of cam pins 5 a, 6 a are attached to the outer circumferences of the lens frames 5, 6. The cam pins 5 a, 6 a are slidably fitted into elongated holes 4 b formed in the rectilinear cylinder 4. Yes. Therefore, the lens frames 5 and 6 can move in the optical axis direction without rotating with respect to the rectilinear cylinder 4.
[0015]
Further, cam pins 5a and 6a penetrating the long holes 4b are fitted to the inner periphery of the male helicoid cylinder 2, and cam grooves (guides) that guide the optical conditions as the male helicoid cylinder 2 is rotated as the male helicoid cylinder 2 rotates. (Not shown in the figure) is formed.
[0016]
In the above configuration, when the drive gear 3 is rotated, the male helicoid cylinder 2 and the rectilinear cylinder 4 are integrally fed out to the fixed female helicoid cylinder 1, and further, the lens frames 5 and 6 can be fed out therefrom. A dynamic zoom lens barrel is constructed.
[0017]
A pedestal 4c is formed on the optical axis end of the rectilinear cylinder 4, and a cylindrical pin 4d is formed on the pedestal 4c. The pin portion 4d is fitted into a groove portion 1e formed on the upper portion of the fixed female helicoid cylinder 1 so as to extend in the optical axis direction, and moves forward and backward in the optical axis direction in accordance with the zoom operation of the lens barrel. The position of the pin portion 4d corresponds to the position of the lens frames 5 and 6 holding the photographing lens group, and the focal length of the photographing lens can be known by detecting the position of the pin portion 4d.
[0018]
Next, a finder optical system that performs a zoom operation in conjunction with the zoom operation of the photographing lens will be described with reference to FIG. A finder cam plate 10 is disposed on the upper part of the fixed female helicoid cylinder 1 of the lens barrel, and this finder cam plate 10 is formed on the outer periphery of the fixed female helicoid cylinder 1 so as to extend in the optical axis direction. The position is restricted by the portions 1 f and 1 g and the flange portion 1 b formed on the entire outer periphery, so that only the circumferential direction of the fixed female helicoid cylinder 1 can be moved.
[0019]
The finder cam plate 10 is further pressed by a finder base plate 11 from above. Hole portions 14a and 15a are formed in the objective lens frames 14 and 15 holding the viewfinder objective lenses 12 and 13, and a finder guide bar 16 passes through the hole portions 14a and 15a. The finder guide bar 16 is fitted in a hole 11a formed at the front end of the finder base plate 11, and guides the finder objective lenses 12 and 13 (objective lens frames 14 and 15) back and forth in the optical axis direction.
[0020]
In order to prevent rotation of the objective lens frames 14 and 15, the dowel portions 14b and 15b formed on the objective lens frames 14 and 15 are fitted into the groove portions 11b formed on the finder base plate 11 so as to extend in the optical axis direction. is doing.
[0021]
Further, a first cam groove 10a is formed on the back side of the finder cam plate 10 (the side with respect to the fixed female helicoid cylinder 1), and the pin portion 4d of the rectilinear cylinder 4 is fitted into the first cam groove 10a. ing. Furthermore, the second and third cam grooves 10b and 10c are formed in the finder cam plate 10, and the dowel portions 14c and 15c of the objective lens frames 14 and 15 are formed in the second and third cam grooves 10b and 10c. Are mated.
[0022]
Here, FIG. 3 shows the cam grooves 10a, 10b and 10c of the finder cam plate 10 in a developed form. The pin 4d is disengaged from the first cam groove 10a when the lens barrel is retracted (in the position indicated by “sink” in a circle). Further, at the wide end, the first cam groove 10a enters the position indicated by a circled "W" in the drawing. At this time, each dowel part 14c, 15c is in a position indicated by a circled "W" in the drawing in the second and third cam grooves 10b, 10c. Even when the lens barrel is retracted, the dowel portions 14c and 15c are in the same position as the wide end position.
[0023]
When the taking lens is fed, by the pin portions 4d pushes the first cam groove 10a, the finder cam plate 10 moves leftward in FIG. 3, the pin portions 4d and dowel portion 14c is at the telephoto end, 15c finder cam The plate 10 moves to a position indicated by a circled “T” in the drawing. For this reason, the objective lens frames 14 and 15 are guided by the cam grooves 10b and 10c, respectively, and move in the optical axis direction.
[0024]
According to such a configuration, when retracted, the pin portion 4d that interlocks the rectilinear cylinder 4 and the finder cam plate 10 is disengaged from the first cam groove 10a, and the finder cam plate 10 is free in the circumferential direction. Therefore, a fixing spring 17 is provided to fix the finder cam plate 10. Specifically, the protrusion 17a of the fixed spring 17 engages with the V groove 10e formed on the end surface 10d of the finder cam plate 10 to hold the finder cam plate 10 between the retracted position and the wide position. Further, between the wide end and the tele end, the end face 10d of the finder cam plate 10 and the fixed spring 17 are in contact with each other, and a frictional force acts between them.
[0025]
The light beams that have passed through the finder objective lenses 12 and 13 that have been zoomed in this way pass through the triangular prism 18 and then form an image with the roof prism 19. Therefore, a viewfinder image can be seen through the roof prism 19 and the eyepiece 20.
[0026]
Next, the focus mechanism of the taking lens will be described with reference to FIG. FIG. 4 is a development view of a cam groove formed inside the male helicoid cylinder 2. The zoom stop position of this camera is four positions indicated by circles “B”, “C”, “D”, and “E” in the drawing. 21 is a cam groove cam pin 5a formed on the outer periphery of the lens frame 5 is fitted, the cam groove 21 is a cam pin 5a of the same number form. Reference numeral 22 denotes a cam groove into which the cam pin 6a formed on the outer periphery of the lens frame 6 is fitted, and the same number of cam grooves 22 as the cam pins 6a are formed.
[0027]
A position indicated by a circle “A” in the figure is a retracted position of the camera, “B” is a wide position, and “E” is a tele position. An area indicated by “F” is a focus feed-out range from infinity to the nearest in the wide area. This focus feed-out range is similarly provided for each position “C”, “D”, “E”.
[0028]
In the “F” region of the cam groove 22, the direction of the cam groove 22 is opposite to the previous direction because the lens frame 6 is moved by an amount equivalent to the amount by which the male helicoid cylinder 2 is extended to the telephoto side. It is for returning. Therefore, in the “F” region, the lens frame 6 does not move at all in the optical axis direction, and only the lens frame 5 moves. Then, by taking out in the “F” region, the photographing lens performs a focusing operation. Note that the focusing operation of the photographing lens is performed by the same operation at each of the other positions “C”, “D”, and “E”.
[0029]
Here, in the extension sequence from the retracted position of the taking lens barrel, as shown by the arrow “I” in FIG. 4, the taking lens is once extended to a position exceeding the focus area “F” and then returned to the infinite end. ing. Similarly, at positions “C”, “D”, and “E” that are stopped by the tele-direction zoom operation sequence, driving is performed as indicated by arrows “II”, “III”, and “IV”. For this reason, when the photographing lens and the finder lens are interlocked with each other in the focus area “F”, the finder lens is displaced with a small amount, and the photographer who is looking at the finder may feel uncomfortable.
[0030]
However, in this embodiment, as shown in FIG. 3, the first cam groove 10a of the finder cam plate 10 is provided with a groove width for preventing the finder optical system from moving during the focusing operation. Thereby, during the tele direction zoom operation of the photographing lens, the pin portion 4d moves along the cam surface 10a ′ of the first cam groove 10a according to the tele direction zoom operation sequence described above, and the viewfinder cam plate 10 is moved to the left in FIG. In the focusing operation, when the pin portion 4d is returned to the position indicated by 4d 'from 4d' when returned to the infinite end by the above-described feeding sequence, the pin portion 4d becomes the position 4d ". It only moves between 4d '. For this reason, the viewfinder objective lenses 12 and 13 move during the zoom operation but do not move during the focus operation. Therefore, the photographer looking through the viewfinder during the focusing operation does not feel uncomfortable.
[0031]
On the other hand, at the positions “B”, “C”, and “D” that are stopped by the zoom operation sequence in the wide direction, as shown by the arrows “I ′”, “II ′”, and “III ′”, from the tele side to the wide side Drive all at once. At this time, as shown in FIG. 3, the finder drives the photographic lens in the retracting direction beyond the focus area F in accordance with the wide-direction zoom operation sequence, so that the pin portion 4d has the first cam groove 10a on the position 4d ″ side. It moves along the cam surface 10a ″ and drives the finder cam plate 10 in the right direction in FIG.
[0032]
According to this, when the photographing lens stops at a certain zoom stop position, it has already stopped at the infinite end (position where the finder cam plate 10 is driven to the right in FIG. 3 and stopped) at that zoom stop position. become. Accordingly, since the pin portion 4d only moves between the positions 4d ″ and 4d ′ during the focus operation, the finder objective lenses 12 and 13 move during the zoom operation in the wide direction but do not move during the focus operation. The photographer looking through the viewfinder during operation does not feel uncomfortable.
[0033]
FIG. 5 shows an electric circuit of the zoom lens barrel of the present embodiment. In this figure, 50 is a CPU for controlling each operation of the camera, 51 is an EEPROM which is a storage medium for each control data, 52 is a motor control circuit for driving 53 lens barrel motors, and 54 is a taking-out lens (drawing-in). It is a pulse count circuit that counts the amount.
[0034]
55 is a SW1 that is turned on when the release button is pressed halfway, 56 is a SW2 that is turned on when the release button is fully pressed, 57 is a TELE SW for performing a TELE zoom operation, and 58 is a WIDE SW for performing a WIDE zoom operation. is there.
[0035]
Reference numeral 59 denotes a lens barrel position SW for detecting the zoom stop position of the photographing lens, and generates a signal at the focus infinite end position of the detected zoom stop position.
[0036]
Next, a zoom operation sequence performed by the CPU 50 will be described with reference to flowcharts shown in FIGS. FIG. 6 is a flowchart showing a tele-direction zoom operation sequence performed by the CPU 50 when the photographer operates the TELE SW 57. FIG. 7 is a flowchart showing a wide-direction zoom operation sequence performed when the WIDE SW 58 is operated.
[0037]
First, the tele direction zoom operation sequence will be described.
[0038]
In step 101, the lens barrel motor 53 is driven in the tele (feed-out) direction by the motor control circuit 52.
[0039]
In step 102, the signal state of the lens barrel position SW59 is determined, and a zoom stop position to be stopped by the photographer is detected.
[0040]
In step 103, in response to the signal of the lens barrel position SW59, the amount of extension of the taking lens is converted into the number of pulses by the pulse count circuit 54, and counting is started.
[0041]
In step 104, the amount of extension of the focus area “F” at the zoom position to be stopped is converted into a pulse amount, and the photographing lens is extended by the pulse amount.
[0042]
In step 105, as described above, in order to prevent the viewfinder from moving during focusing, the amount that is further extended beyond the focus area “F” is converted into the number of pulses, and the photographing lens is extended by the amount of the pulse.
[0043]
In step 106, in step 104 and step 105, the photographing lens is extended by a predetermined amount, and the pulse count is finished.
[0044]
In step 107, the lens barrel motor 53 is reversely rotated by the motor control circuit 52 and driven in the wide (retracting) direction.
[0045]
In step 108, the signal state of the lens barrel position SW is determined, and the photographing lens is retracted to the infinite end position of the zoom stop position to be stopped.
[0046]
In step 109, the lens barrel motor 53 is stopped by the motor control circuit 52.
[0047]
Here, the viewfinder field ratio is obtained when the photographing lens is further extended beyond the focus area “F” in Step 105 of the tele-direction zoom operation sequence (when the viewfinder cam plate 10 is driven leftward in FIG. 3). ), The photographic lens and viewfinder lens move in conjunction with each other. For this reason, the field-of-view ratio is stored by storing the adjustment amounts “IIa”, “IIIa”, and “IVa” for correcting variations in the field-of-view due to mechanical manufacturing errors in the storage unit provided in the EEPROM 51 for each zoom stop position. Is set to an appropriate value.
[0048]
Similarly, in the extension sequence from the retracted position, when the photographer operates the main SW (not shown) to turn on the power, the same control as the tele-direction zoom operation sequence is performed, and the adjustment amount “Ia” is stored. The field of view is set to an appropriate value.
[0049]
Next, the wide direction zoom operation sequence will be described.
[0050]
In step 121, the lens barrel motor 53 is driven in the wide (retracting) direction by the motor control circuit 52.
[0051]
In step 122, the signal state of the lens barrel position SW59 is determined, a zoom stop position to be stopped by the photographer is detected, and the taking lens is retracted to the infinite end position of the zoom stop position.
[0052]
In step 123, the signal of the lens barrel position SW59 is received, the amount of retraction of the photographing lens is converted into the number of pulses by the pulse count circuit 54, and counting is started.
[0053]
In step 124, the correction retraction amount with the field of view of the zoom stop position to be stopped adjusted in step 105 of the tele-direction zoom operation sequence is converted into the number of pulses, and the photographing lens is retreated by the pulse amount.
[0054]
In step 125, in step 122 and step 124, the photographing lens is brought back by a predetermined amount, and the pulse count is finished.
[0055]
In step 126, the lens barrel motor 53 is stopped by the motor control circuit 52.
[0056]
Here, the viewfinder field ratio is determined when the photographing lens is further retracted beyond the infinite end of the focus area in step 124 of the wide-direction zoom operation sequence (when the viewfinder cam plate 10 is driven rightward in FIG. 3). ), The field of view is set in conjunction with the taking lens and the viewfinder lens. For this reason, the storage unit provided in the EEPROM 51 is adjusted to correct the deviation from the field of view ratios “Ia”, “IIa”, and “IIIa” determined by the tele-direction zoom operation sequence due to mechanical manufacturing errors or the like at the same zoom position. By storing the amounts “Ib”, “IIb”, and “IIIb” for each zoom position, the field of view rate is set to an appropriate value.
[0057]
Note that, at the zoom stop position “E”, that is, at the telephoto end, it can be adjusted only by the telescopic zoom operation, and therefore “IVb” need not be set.
[0058]
As described above, in the zoom stop positions of “B”, “C”, and “D”, the viewfinder field ratio at the time of zooming in the tele direction is set to the adjustment amounts “Ia”, “IIa”, “IIIa” of the photographing lens position, respectively. By adjusting with, and adjusting the viewfinder field ratio during zooming in the wide direction with the adjustment amounts “Ib”, “IIb” and “IIIb” of the photographing lens position, an appropriate field ratio can be obtained regardless of the zoom operation direction. .
[0059]
The present invention can be applied to various types of cameras, optical devices, and other devices having a zoom finder.
[0060]
【The invention's effect】
As described above, according to the present invention, for each zooming direction, the first and second movement amounts ( position adjustment amounts ) of the photographic lens that provide the appropriate field of view of the finder at the zoom stop position are set. Therefore, the viewfinder field ratio at the zoom stop position can be set appropriately regardless of the zooming direction.
[0061]
Further, when a plurality of zoom stop positions are provided, if the movement amount (first and second movement amounts) of the photographing lens in each zooming direction is set for each zoom stop position, all the zoom stop positions are set. The viewfinder field ratio can be set appropriately regardless of the zooming direction at the zoom stop position.
[0062]
In these inventions, by keeping the amount of movement of the imaging lens in each zoom direction (first and second moving amount) is stored and held in storage means such as EEPROM, to obtain the above effects with a simple structure Can do.
[Brief description of the drawings]
FIG. 1 is a perspective view of a zoom lens barrel of a camera according to a first embodiment of the present invention.
FIG. 2 is a perspective view showing the zoom lens barrel and a finder zoom mechanism.
FIG. 3 is a plan view of a finder cam plate of the finder zoom mechanism.
FIG. 4 is a development view of a zoom cam groove formed in the zoom lens barrel.
FIG. 5 is a block diagram of an electric circuit of a lens barrel driving portion of the camera.
FIG. 6 is a flowchart showing a tele-direction zoom operation sequence in the camera.
FIG. 7 is a flowchart showing a wide-direction zoom operation sequence in the camera.
[Explanation of symbols]
4). Straight cylinder 4d. Pin part 10. Viewfinder cam plate 10a. First cam grooves 12, 13. Viewfinder objective lens 21, 22. Cam groove 51. EEPROM
54. Pulse count circuit

Claims (4)

An imaging optical system, cam means for driving the imaging optical system, a finder optical system linked to the zooming drive of the imaging optical system by the cam means and not linked to focusing driving, and driving of the cam means are controlled. In an optical instrument having a control means ,
The cam means has a focusing drive region used for focusing drive of the photographing optical system, and a zooming drive region used for zooming drive of the photographing optical system on both sides of the focusing drive region,
The control means have a row position adjustment of the finder optical system by moving the photographing optical system from the focusing drive region zooming driving region of the cam means during zooming by the zoom stop position in the telephoto direction and wide-angle direction,
The control means includes a first movement amount from the focusing drive region of the photographing optical system to the zooming drive region during zooming in the tele direction and a focusing drive region of the photographing optical system during zooming in the wide direction. An optical apparatus characterized in that a second movement amount to the zooming drive region is set. 2. The optical apparatus according to claim 1, wherein a plurality of zoom stop positions are provided, and the control unit sets the first and second movement amounts for each zoom stop position. The optical apparatus according to claim 1, wherein the control unit includes a storage unit that stores and holds the first and second movement amounts.   The optical apparatus according to claim 3, wherein the storage unit is an EEPROM.

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