JP2005274977A - Camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camera which is inexpensive and compact even when a high-performance zoom finder is mounted. <P>SOLUTION: An oblique advancing plate 105A is moved in an oblique direction interlocked with the elongation and contraction of a lens barrel. By utilizing the oblique movement, cam grooves 1051A and 1052A whose tilt angle is gentle are provided on the plate 105A so as to move lenses for adjusting the angle of visibility 1021A and 1022A in an optical axis direction. Thus, the high-performance and compact zoom finder freely finely adjusting the angle of visibility is constituted. Then, the camera is made compact by mounting the compact zoom finder in the camera. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a camera that incorporates a photographing optical system with a variable focal length, includes a lens barrel that expands and contracts in the optical axis direction and adjusts the focal length of the photographing optical system, and captures a subject with the photographing optical system. .

  Some cameras have an optical zoom function, and many of them have a zoom lens built in a lens barrel and extend the lens barrel to extend the zoom function. Many of such cameras are equipped with a zoom finder that changes the viewing angle of the finder optical system in accordance with the movement of the lens barrel.

  In order to adjust the viewing angle of the zoom finder with high accuracy, a mechanism for adjusting the visual field size with the expansion and contraction of the lens barrel is required.

  As a mechanism for accurately adjusting the viewing angle according to the expansion and contraction of the lens barrel, a pin is provided on the lens barrel side, and a cam mechanism is operated in conjunction with the expansion and contraction of the lens barrel (for example, Patent Documents). 1) and a gear for adjusting a viewing angle is connected to a part of a gear train arranged on the lens barrel side, and a cam mechanism is operated by the gear to adjust the viewing angle (see, for example, Patent Document 2). ). In any case, in such a mechanism for adjusting the viewing angle, the cam mechanism is used to adjust the viewing angle with high accuracy.

  A typical cam mechanism includes a cam cylinder having a cam groove and a cam plate having a cam groove. However, if the cam cylinder is used, there is a problem that the camera is inevitably enlarged by the diameter of the cam cylinder. At present, cam plates are often used.

  FIG. 1 is a diagram showing a configuration of a zoom finder 100 having a cam plate 105.

  In FIG. 1, when the lens barrel is in the extended state, the telephoto lens is set to TELE (telephoto), and each of the two moving lenses is held at positions j and k on the objective lens side (a position indicated by a dotted line in the drawing). When the lens barrel is in a contracted state, WIDE (wide angle) is set, and the two moving lenses 1021 and 1022 are held at the positions m and n (positions indicated by solid lines in the drawing) on the eyepiece lens 104 side, respectively. It is shown. In the configuration shown in FIG. 1, the two moving lenses 1021 and 1022 in the finder optical system are moved together with the lens holding frames 1021L and 1022L from the positions m and n shown in FIG. 1 to the positions j and k shown in FIG. The cam grooves 1051 and 1052 have a predetermined inclination angle, and the cam plate 105 having the cam grooves is moved in a direction indicated by an arrow in the figure (hereinafter referred to as a lateral direction). In other words, the movable lens 1021, 1022 is moved in the optical axis direction by moving the cam plate 105 in the horizontal direction according to the expansion and contraction of the lens barrel, and the movable lenses are arranged at appropriate positions according to the operation of the zoom switch. doing. In this way, each moving lens is arranged at an appropriate position according to the operation of the zoom switch, and subject light incident from the objective lens 101 passes through each moving lens 1021, 1022, and further, the objective prism 103a, the focusing screen 103b, and the eyepiece. It reaches the viewfinder eyepiece through the roof prism 103c.

  As can be seen from FIG. 1, since it is impossible to mount a member in a portion including the range in which the cam plate 105 moves in the lateral direction (the range up to the portion indicated by the dotted line in the figure), the finder optical An objective prism 103a, a focusing screen 103b, and an eyepiece roof prism 103c are disposed at the end of the system, and the finder optical system has high optical performance. These three optical components are relatively expensive.

  Here, the action of the inclination angle of the cam grooves 1051 and 1052 provided to move the two moving lenses 1021 and 1022 in the optical axis direction in accordance with the lateral movement of the cam plate 105 will be described.

  As shown in FIG. 1, cam grooves 1051 and 1052 having an inclination angle are provided on the surface of the cam plate 105 in correspondence with the two moving lenses. The cam grooves 1051 and 1052 having these inclination angles have a converting action for converting any of the horizontal movements of the cam plate 105 into the vertical direction, that is, the optical axis direction.

  As the inclination angles of the cam grooves 1051 and 1052 are gentler, the positions of the two moving lenses 1021 and 1022 are finely adjusted, and the viewing angle of the zoom finder is finely adjusted according to the operation position of the zoom switch. . When this inclination angle is made steep, the lateral length of the cam plate 105 is shortened, and the range in which the cam plate 105 moves can be narrowed, but the viewing angle adjustment accuracy deteriorates. Further, since the direction of the force is changed, if the inclination angle is made too steep, it may stop moving, and there is a limit to the inclination angle that can be used.

  In this way, the higher the performance of the zoom finder, the slower the tilt angle must be to maintain the viewing angle adjustment accuracy, and the larger the cam plate, the greater the travel distance of the cam plate. There is a problem of becoming.

When the cam plate becomes large and the moving distance of the cam plate becomes large in this way, a large arrangement space is required inside the camera, and the camera becomes large. Further, there is no space for arranging the prisms constituting the zoom finder, and there is a restriction that a relatively expensive prism must be used.
Japanese Patent No. 2572678 JP 2003-222777 A

  In view of the above circumstances, an object of the present invention is to provide an inexpensive and small camera even if a high-performance zoom finder is mounted.

The camera of the present invention that achieves the above object includes a photographic optical system having a variable focal length, and includes a lens barrel that expands and contracts in the optical axis direction to adjust the focal length of the photographic optical system. In a camera that captures and shoots,
A zoom finder that adjusts the viewing angle in conjunction with the expansion and contraction of the lens barrel in the optical axis direction,
The zoom finder
An oblique member that moves obliquely with respect to the optical axis in conjunction with the expansion and contraction of the lens barrel;
And a visual field adjusting member that adjusts the visual field of the finder by receiving a driving force from the skew member and moving in the optical axis direction.

  According to the camera of the present invention, the skew member is moved obliquely, and the visual field adjusting member moves in the optical axis direction upon receiving a driving force from the oblique member moved obliquely.

  In the present situation, the visual field adjustment member was moved in the optical axis direction by moving the cam plate in the lateral direction, but instead of the conventional cam plate, the skew member is made to act as the cam plate, The moving distance in the horizontal direction can be reduced by moving the skew member diagonally. Furthermore, if the slanting member is used to move obliquely, it becomes easy to provide the cam member with a cam groove equivalent to that provided with a cam groove having a gentle inclination angle in the conventional cam plate. By moving the visual field adjustment member along the cam groove to the optical axis, the visual field angle is adjusted with high accuracy without increasing the size of the skew member. In this way, it is possible to move with a light driving force because the direction of the force is less changed as much as it is moved obliquely than before.

  Further, since the movement distance is reduced, the left and right arrangement spaces are reduced as compared with the past, and a free space is secured in the axial direction intersecting the direction in which the skew member moves obliquely. Then, there is a degree of freedom in the arrangement space of the optical parts constituting the zoom finder, and it becomes possible to mount a relatively inexpensive Porro prism in the empty space, the downsizing of the skew member and the moving distance The reduction in size and the cost can be achieved together with the reduction of the above.

  In the camera of the present invention, the viewing angle is adjusted in conjunction with the expansion and contraction of the lens barrel, that is, the movement of the lens barrel is transmitted to the field adjustment member via a pin or the like, and the field adjustment member is expanded and contracted by the lens barrel. However, the present invention is not limited to this, and can be applied even if the mechanism for driving the zoom finder uses, for example, a gear train.

  That is, the skew member may be moved obliquely with respect to the optical axis upon receiving a driving force from the operation of expanding and contracting the lens barrel.

  Further, in any drive mechanism, the skew member preferably has an inclined end surface extending in the moving direction of the skew member.

  When an inclined end surface extending in the moving direction of the oblique light member is provided on the oblique member, a further vacant space is secured on the inclined end surface portion, and a prism or the like is mounted in the vacant space as required, and the zoom finder is downsized. The camera equipped with the zoom finder is also downsized.

   As described above, even if a high-performance zoom finder is installed, an inexpensive and small camera can be realized.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 2 is a perspective view showing an appearance of a camera according to an embodiment of the present invention.

  As shown in FIG. 2, a lens barrel 11 is provided at the center of the camera body 1a, and a photometric window 12, an AF window 13, an objective window 1010A of the zoom finder 100A, and the like are disposed above the lens barrel 11. ing. An objective lens is fitted in the objective window 1010A. A flash light emission window 14 is provided beside the objective window 101A of the zoom finder 100A, and a release button 15 is provided on the upper surface of the camera body 1a. Further, a finder eyepiece 101A of the zoom finder 100A is provided on the rear side.

  FIG. 3 is a view showing the back of the camera of FIG.

  As shown in FIG. 3, a display panel 16 is provided on the back side of the camera body 1 a, and a finder eyepiece 101 </ b> A of the zoom finder is provided above the display panel 16. An eyepiece 104A is fitted into an eyepiece window 1040A of the finder eyepiece 101A, and a macro button 101B and a macro display portion 101C are provided on the finder eyepiece 101A. A zoom switch 17 is provided on the side of the viewfinder eyepiece 101A, and a power switch 18 for turning on the power is provided on the lower right side of the display panel 16.

  Shooting is performed with a camera having such an appearance.

  FIG. 4 is a view of the inside of the camera with the exterior cover 1a and the zoom finder 100A removed.

  In the center of FIG. 4 is a fixed frame 111 containing the lens barrel, and a rectilinear cylinder 112 for expanding and contracting the lens barrel is disposed inside the fixed frame 111 so as to be able to advance and retract. Further, an interlocking pin 113 that moves in conjunction with the forward and backward movement of the rectilinear cylinder 112 is disposed above the fixed frame 111, and the field of view of the zoom finder 100A is moved by moving the interlocking pin 113 back and forth in the optical axis direction. The corner is adjusted.

  In the camera of this embodiment, the lens barrel driving motor 120 shown in the lower part of FIG. 4 is rotated in accordance with the operation of the zoom switch 17, and the driving force from the rotated motor is transmitted to the straight cylinder by the gear train 121. Thus, the straight barrel 112 is moved back and forth to extend and retract the lens barrel. In FIG. 4, the zoom switch 17 is fully operated on the WIDE side, the position Y of the interlocking pin 113 when the straight cylinder 112 advances forward is indicated by a solid line, and the zoom switch 17 is fully operated on the TELE side. The position Z of the interlocking pin 113 when the rectilinear cylinder 112 advances further forward and the position X of the interlocking pin 113 when the power switch is cut off and the rectilinear cylinder 112 retracts from the front side are indicated by dotted lines, respectively. Yes.

  That is, when the zoom switch 17 is fully operated after the power switch 18 is turned on and the rectilinear cylinder 112 has moved forward from the camera body, the interlocking pin 113 is moved from the position indicated by the symbol X shown in FIG. When the zoom switch 17 is moved to the WIDE side when the zoom switch 17 is moved to the Y position and further moved to the position indicated by the reference sign Z and is at the position indicated by the reference sign Z, the interlocking pin 113 is moved in the Y direction indicated by the reference sign Y in FIG. When the zoom switch 17 is further fully operated on the WIDE side, the interlocking pin 113 moves to the position indicated by the symbol Y. When the power is turned off, the interlocking pin 113 moves to the position indicated by the symbol X, the rectilinear tube 112 moves backward into the camera, and the lens barrel is retracted. This interlocking pin 113 is engaged with a skew plate 105A which is a skew member according to the present invention.

  FIG. 5 shows the skew plate 105A extracted. FIG. 5 shows a view of the skew plate 105A from the lens barrel side so that the cam groove 1050A engaged with the interlocking pin 113 can be seen. 5 is the direction in which the subject light is incident, and the subject image based on the incident subject light is visually recognized through the eyepiece 114A of the zoom finder located diagonally to the left. Is done. As can be seen from FIG. 5, when the interlocking pin 113 moves, the skew plate 105 moves obliquely (in the direction of the arrow) with respect to the light incident path of the finder optical system, that is, the optical axis.

 5 is interlocked with the lens barrel 11 extending forward when the zoom switch 17 shown in FIG. 2 is operated to the TELE side, and the interlocking pin 113 reaches the Z position described in FIG. The skew plate 105A moves obliquely upward to the left along the arrow direction in the figure. When the zoom switch 17 shown in FIG. 2 is operated to the WIDE side, the interlocking pin 113 moves to the Y position described with reference to FIG. It moves to the lower right diagonally downward along the arrow direction.

  The visual field adjustment member that moves in conjunction with the oblique movement of the skew plate 105A shown in FIG. 5 will be described.

  FIG. 6 is a view showing the relationship between the skew plate 105A and the two moving lenses 1051A and 1052A which are visual field adjusting members.

  The configuration is the same as that in FIG. 1 except that a skew plate 105A is provided instead of the cam plate 105 in FIG. 1, the configuration of the prism 103A is changed, and a mirror 1030A is added. . 6 is the direction in which the subject light is incident, and the subject image based on the incident subject light passes through the eyepiece 104A of the zoom finder located obliquely on the left. Visible.

  In FIG. 6, the movement of the skew plate 105A is shown in a stepwise manner, and the skew plates 105A arranged at three positions are overlapped by dotted lines.

  The finder optical system constituting the zoom finder 100A includes an objective lens 101A, two lenses 1021A and 1022A that are field-of-view adjusting members, a Porro prism 103A, and a mirror 1030A, and an object that has entered the objective lens 101A. The light is passed through two moving lenses 1021A and 1022A arranged with high precision in accordance with the objective lens 101A and the optical axis of the prism, and the traveling direction of the subject light is bent by the prism 103A to exit the prism 103A. The subject image is formed on the focal plane F located at. The subject image formed on the focal plane F is visually recognized through the mirror 1030A by the photographer looking through the eyepiece window 1010A of the viewfinder eyepiece 101A.

  According to the configuration of the zoom finder of this embodiment, the two moving lenses 1021A and 1022A for adjusting the viewing angle, the objective lens 101A, and the prism 103A are integrally held by the two guide shafts 102A and 1020A. Therefore, the optical axis of the finder optical system is always kept constant even when the moving lenses 1021A and 1022A for adjusting the viewing angle are moved along the guide axes 102A and 1020A.

  A skew plate 105A that moves obliquely in conjunction with the movement of the lens barrel is disposed below the zoom finder optical system in which such an optical axis is obtained with high accuracy. As described with reference to FIG. 5, a cam groove 1050A for engaging with the interlocking pin 113 of the lens barrel is formed on the lower surface of the skew plate 105A, and along the oblique movement of the skew plate 105A on the upper surface. Two cam grooves 1051A and 1052A for moving the moving lenses 1021A and 1022A for adjusting the viewing angle are provided corresponding to the two moving lenses. As can be seen from FIG. 6, these cam grooves 1051 </ b> A and 1052 </ b> A have a gradual inclination angle and a substantially linear shape without an inclination angle as compared with those in FIG. 1. Thus, by moving the slanting plate 105A obliquely, a cam groove with a gentle inclination angle can be easily provided, and the moving distance in the lateral direction of the cam plate 105A can be reduced by the amount of further oblique movement. Can do. Furthermore, the size of the skew plate 105A itself can be reduced as compared with the conventional cam plate.

  The oblique plate 105A is guided by a guide boss 1056A and moves stably and obliquely. The guide boss 1056A is inserted into a guide groove provided in the camera body.

  Therefore, by moving the slanting plate 105A in an oblique direction in a stable state, the position of the lens holding frame that engages the gentle cam groove provided on the slanting plate 105A is controlled with high accuracy, and the viewing angle is increased. Adjusted with high accuracy.

  Further, in the example of the present embodiment, an inclined end face 1055 extending in the moving direction of the skew plate 105A is provided on the skew plate in order to make the skew plate as small as possible and secure an empty space. When the inclined end surface 1055A is provided on the oblique plate 105A in this way, an empty space is secured on the diagonal axis side orthogonal to the moving axis with the direction in which the oblique plate 105A moves obliquely as a moving axis. An eyepiece 104A and a mirror 1030A can be provided in the space. For this reason, it is possible to configure a finder optical system using an inexpensive prism.

  As described above, the swash plate 105A becomes smaller, and the finder optical system is configured by using the empty space secured on the diagonal axis orthogonal to the moving axis of the swash plate to make the camera body compact. It becomes. At this time, it is not necessary to use the expensive roof prism group used in the conventional example, and an inexpensive polo prism can be used, so that the zoom finder can be made inexpensive. In addition, the load on the motor that drives the lens barrel is reduced by the reduction in the size of the skew plate 105A, and the motor can be reduced in size and cost.

  As described above, when the zoom finder mounted on the camera is reduced in size and cost, and further, when the motor for driving the straight cylinder is reduced in size and price is reduced, these components are incorporated in the camera. Miniaturization and cost reduction are achieved.

It is a figure which shows the structure of the zoom finder which the conventional camera has. It is the perspective view which looked at the external appearance of the camera which is embodiment of this invention from front diagonally upward. It is the perspective view which looked at the appearance of the camera which is an embodiment of the present invention from the back slanting upper part. It is the figure which removed the camera body and zoom finder part of the camera of FIG. 2, FIG. 3, and looked at the inside of a camera. It is the figure which extracted and showed the skew member. It is a figure which shows the relationship between a skew board and a visual field adjustment member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Camera 1a Camera body 11 Lens barrel 12 Metering window 13 AF window 14 Flash emission window 15 Release button 16 Display panel 100 100A Zoom finder 101 101A Objective lens 1010A Objective window 102 102A 1020A Guide shaft 1021 1021A Moving lens 1021L Lens holding frame 1022L Lens holding frame 1022L Moving lens 1022L Lens holding frame 103 103A Prism 1030A Mirror 104 104A Eyepiece 1040A Eyepiece window 105 Cam plate 1051 1052 Cam groove 105A Skew plate 1051A 1052A Cam groove 1055A Inclined end face 1056A Guide boss F Focal plane

Claims (3)

In a camera that incorporates a photographing optical system with a variable focal length, includes a lens barrel that expands and contracts in the optical axis direction and adjusts the focal length of the photographing optical system, and captures a subject with the photographing optical system.
A zoom finder whose viewing angle is adjusted in conjunction with expansion and contraction of the lens barrel in the optical axis direction,
The zoom finder
An oblique member that moves obliquely with respect to the optical axis in conjunction with expansion and contraction of the lens barrel;
A camera comprising: a visual field adjustment member that receives a driving force from the skew member and moves in the optical axis direction to adjust the visual field of the finder.   The camera according to claim 1, wherein the skew member moves obliquely with respect to the optical axis upon receiving a driving force from an expansion / contraction operation of the lens barrel.   The camera according to claim 1, wherein the skew member has an inclined end surface extending in a moving direction of the skew member.

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