JPH11316403A - Electronic camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic camera in which an electronic zoom area is covered with the optical zoom area of a finder optical system in a constitution without the restriction on a device layout and a complicated mechanism. SOLUTION: This camera is provided with a photographing optical system, a CCD 31 converting an image formed by the photographing optical system to an electrical signal, an electronic zooming function enlarging one part of the image and a finder optical system provided with an optical zoom area, including an electronic zoom area. Then, the variable power of the finder optical system is executed by a driving mechanism which is independent of the photographing optical system.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic camera which electrically captures an image signal using an image pickup device such as a CCD.

[0002]

2. Description of the Related Art In a conventional camera equipped with a real image type viewfinder, a zooming operation of a photographing optical system and a zooming operation of a viewfinder optical system are mechanically linked as proposed in Japanese Patent Application Laid-Open No. 7-64141. Various products have been proposed.

If the magnification of the finder optical system of the conventional camera and the magnification of the photographing optical system are the same, or if the magnification of the real image finder is lower than that, a separate liquid crystal monitor or the like is used. Was compatible.

In addition, as proposed in Japanese Patent Application Laid-Open No. Hei 6-133199, in a camera with a real image type finder linked by a mechanical mechanism, the magnification of the photographic optical system is lower than that of the finder optical system. There is also proposed an apparatus in which an equal lift cam is formed at the end of the telecam end of the mechanical cam for moving the camera, and an electronic zoom is used in the area of the equal lift cam in conjunction with the optical zoom of the real image type optical viewfinder.

[0005]

However, in the conventional camera with a finder, the following operations are performed because the zooming operation of the photographing optical system and the zooming operation of the finder system are mechanically linked. There were serious disadvantages.

1) The design layout of the photographing optical system and the finder optical system is limited.

2) When the electronic zoom is performed by the photographing optical system and the liquid crystal monitor or the like is used, the power consumption increases.

3) In an optical finder that is linked with a mechanism, as proposed in Japanese Patent Application Laid-Open No. Hei 6-133199, a complicated mechanical position correction mechanism is required to adjust the field of view of the photographing optical system.

The present invention solves the above-mentioned drawbacks of the prior art, does not limit the layout of the apparatus, and does not have a complicated mechanism, and covers the electronic zoom range with the optical zoom range of the viewfinder optical system. It is an object of the present invention to provide an electronic camera capable of performing such operations.

[0010]

In order to achieve the above object, an electronic camera according to the present invention comprises: a photographing optical system; an image pickup device for converting an image formed by the photographing optical system into an electric signal; An electronic camera having an electronic zoom function for enlarging a part of the electronic camera, comprising a finder optical system having an optical zoom region including the electronic zoom region, wherein the finder optical system is driven by a driving mechanism independent of the photographing optical system. It is characterized by performing zooming of the system.

[0011]

FIG. 1 is a schematic diagram showing a photographing optical system and a finder optical system of an electronic camera according to an embodiment of the present invention, and respective driving mechanisms and control value circuits.

In this embodiment, the photographing optical system includes a field lens 1, a variator lens 2, an afocal lens 3, and a focus lens 4, and each of the variator lens 2 and the focus lens 4 is a mirror. It is held by frames 7 and 8, and is guided along the guide bars 5 and 6 so as to be able to advance and retreat in the optical axis direction.

The racks 7a, 7a,
8a and the threaded rod portions 9a and 10a of the stepping motors 9 and 10 which are the driving sources are connected to each other by urging means (not shown).
The variator lens 2 and the focus lens 4 respectively move forward and backward in the optical axis direction when the stepping motors 9 and 10 rotate forward / reversely without play.

The respective initial positions of the variator lens 2 and the focus lens 4 are detected by each of the photointerrupters 11 and the photointerrupter 11 in which the light emitting element and the light receiving element are integrated.
12 is detected by the passage of each of the light blocking members 7b and 8b provided on the movable lens frame.

On the other hand, the finder optical system comprises moving lenses 13 and 14, a field lens 15, a prism 16
And an eyepiece 17, and each movable lens 13,
Reference numeral 14 is held by each of the lens frames 20 and 21 and is guided along the respective guide bars 18 and 19 so as to be able to advance and retreat in the optical axis direction.

The convex portions 20a and 21a provided on the lens frames 20 and 21 respectively contact the cam grooves 22a and 22b of the cam ring 22, and the gear portion 22c of the cam ring 22 and the gear reducer 23a The output gear 23b of the stepping motor 23 having the gears meshes with each other.
Numeral 4 moves forward and backward in the direction of the optical axis to change the magnification.

The initial position of the cam ring 22 is detected when the light interrupting member 22d provided on the cam ring 22 passes through the photo interrupter 24.

The drive / control circuit controls each motor driver 25, 26, 27 for driving each stepping motor, an image processing device 28 for processing a video input from an image pickup device (CCD) 31, and a position control of a moving lens group. Microcomputer 29 to perform
Switch 3 for inputting the direction of telephoto and wide-angle
0, a shutter button 32 and the like.

In the internal storage device (memory) 33 of the microcomputer 29 in FIG. 1, each position of the telephoto end and the wide angle end with respect to the initial position of the variator lens 2 of the photographing optical system is determined by the number of steps corresponding to the rotation amount of the stepping motor 9. It is recorded in.

The position data determined by the distance and the position of the variator with respect to the initial position of the focus lens 4 is stored in the number of steps corresponding to the rotation amount of the stepping motor 10. That is, the zooming operation of the photographing optical system is controlled by a rear focus zoom electronic cam system generally used in video cameras.

After the photographing optical system and the finder optical system are mechanically fixed and the field ratio of the finder optical system to the photographing optical system is adjusted, the respective adjustments to the initial position of the cam ring 22 of the finder optical system are performed. The determined positions of the telephoto end and the wide-angle end are stored in the internal storage device of the microcomputer 29 with the number of steps corresponding to the rotation amount of the stepping motor 23.

The feature of this embodiment is that the viewfinder optical system has a wide optical zoom range including the electronic zoom range of the photographing optical system as shown in FIG. This will be described in more detail below.

As described above, in the internal storage device 33 of the microcomputer 29 shown in FIG. 1, the positions on the telephoto side and the wide angle side with respect to the initial position of the variator lens 2 of the photographing optical system correspond to the steps corresponding to the rotation amount of the stepping motor 9. Stored in numbers. Further, position data determined by the distance and the position of the variator with respect to the initial position of the focus lens 4 is also stored by the number of steps corresponding to the rotation amount of the stepping motor 10.

On the other hand, at the end of the optical telephoto end of the photographing optical system according to the present embodiment, there is a so-called electronic zoom area for enlarging a part of image data as shown in FIG.

On the other hand, the cam ring 22 of the finder optical system is designed so that the visual field ratio with respect to the photographing optical system is set ahead of the zoom region corresponding to the entire zoom region including the electronic zoom region of the photographing optical system. Over Wid for adjustment
It has an e area and an Over Tele area.

After the photographic optical system and the finder optical system are mechanically fixed to adjust the field of view of the finder with respect to the photographic optical system, each adjusted telephoto side with respect to the initial position of the cam ring 22 of the finder optical system. The position on the wide-angle side is the number of steps corresponding to the rotation amount of the stepping motor 23, and is stored in the internal storage device 33 of the microcomputer 29 in FIG.
Is stored.

The operation of the optical system drive control device of this embodiment will be described with reference to the flowchart shown in FIG.

First, when the power is turned on, a setting is made to move the variator lens 2, the focus lens 4, and the cam ring 22 of the finder optical system to the respective initial positions (step S101). Thereafter, each movable lens is positioned at an arbitrary position where the ratio of the magnification of each optical system becomes a predetermined value (step S102).

After the positioning is completed, the microcomputer 29 determines the input signal of the zoom switch 30, and performs a zoom operation in which the zooming operation of the finder optical system and the photographing optical system are linked (step S103).

When the photographing optical system reaches the telephoto end and the zoom switch 30 continues to output a signal to the telephoto side, the variator lens 2 stops and enters a so-called electronic zoom range in which a part of the image data of the image pickup device is enlarged. . On the other hand, the finder optical system is a real image finder zoom that covers the electronic zoom range as described above.

That is, when zooming from the wide-angle side to the telephoto side, in step S104, the microcomputer 29 determines whether or not the current zoom position of the photographing optical system is in the optical zoom range. If it is in the optical zoom range, step S1
In step 05, the optical zoom of the photographing optical system is further performed. On the other hand, if it is not the optical zoom range, it is determined in step S106 whether or not the telephoto end of the electronic zoom range. If it is at the telephoto end of the electronic zoom range, the process proceeds to step S114 described below. If it is not at the telephoto end, electronic zooming of the photographic optical system is performed in step S107.

In step S108, each moving lens of the finder optical system is moved to a zoom position that matches the zoom position of the photographing optical system. Here, in this flow, steps S105 and S108 or step S10
7 and S108 are depicted as proceeding sequentially, but in practice these steps proceed almost simultaneously.

On the other hand, when zooming from the telephoto side to the wide-angle side, in step S109, the microcomputer 29 determines whether the current zoom position of the photographing optical system is at the wide-angle end. If it is the wide-angle end, the process proceeds to step S114 described below,
If it is not the wide angle end, it is determined in step S110 whether or not it is in the optical zoom range. If it is in the optical zoom range, the flow advances to step S111 to perform optical zooming of the photographing optical system.
On the other hand, if it is not in the optical zoom range, the flow advances to step S112 to perform electronic scaling.

In step S113, each moving lens of the finder optical system is moved to a zoom position that matches the zoom position of the photographing optical system. Steps S111 and S113 or steps S112 and S113 proceed almost simultaneously, as in the case of zooming from the wide-angle side to the telephoto side.

In step S114, the microcomputer 29
Determines whether the shutter switch 32 is on or off. If the shutter switch 32 is off, the process proceeds to step S117 described below. If the shutter switch 32 is on, the focus lens 4 of the photographing optical system is driven to perform a focus operation in step S115, and when focus is determined, recording is performed in step S116. Recording is performed on a magnetic / optical recording medium or a memory. When the recording is completed, it is checked in step S117 whether the power of the camera body has been turned off. When the power off operation is confirmed, the power is turned off. If the power-off operation is not performed, the process returns to step S103.

In the above embodiment, the photographing optical system performs optical zoom. Of course, only the photographing optical system has a single focal point, and an electronic zoom for enlarging a part of the image data of the image pickup device and a real image type optical viewfinder. An optical zoom interlocking lens system may be used.

In the present embodiment, the respective lens barrels of the photographing optical system and the finder optical system are made independent of the driving operation, the zoom is interlocked by electric control, and the finder optical system is extended to the electronic zoom range of the photographing optical system. By having a zoom magnification to cover, 1) the layout of the photographing optical system and the finder optical system can be freely designed.

2) When the electronic zoom is performed by the photographing optical system, the viewfinder responds and does not use a liquid crystal.
It is energy saving.

3) Since the electronic zoom can be used in the photographing optical system, the size of the lens unit can be reduced.

4) Since the positions of the moving lens groups such as the telephoto end and the wide angle end of the photographing optical system and the finder optical system are controlled by the number of steps from each center, the relative relationship between the two optical systems is adjusted by the number of steps. It can be done simply by changing.
There is such an effect.

[0041]

As described above, according to the present invention,
The electronic zoom range can be covered by the optical zoom range of the finder optical system with a configuration that is not subject to restrictions on the device layout and has no complicated mechanism.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a camera according to an embodiment.

FIG. 2 is a diagram illustrating a relationship between a variable power range of a photographing optical system and a finder optical system.

FIG. 3 is a flowchart for explaining the operation of the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Field lens 2 Variator lens 3 Afocal lens 4 Focus lens 2, 6, 18, 19 Guide bar 7, 8, 10, 21 Moving lens frame 9, 10, 23 Stepping motor 11, 12, 24 Photo interrupter 13, 14, Viewfinder Moving lens 15 Field lens 16 Prism 17 Eyepiece 22 Cam ring 25, 26, 27 Motor driver 28 Image processing device 29 Microcomputer 30 Zoom switch 31 CCD 32 Shutter button 33 Memory

Claims (2)

[Claims] An imaging device that converts an image formed by the imaging optical system into an electric signal;
An electronic camera having an electronic zoom function of electrically enlarging a part of the image, comprising a finder optical system having an optical zoom region including the electronic zoom region, and being independent of the imaging optical system. An electronic camera, wherein a magnification of the finder optical system is changed by a driving mechanism. 2. The electronic camera according to claim 1, wherein the photographing optical system is a single-focus optical system.