JPH06337464A - Camera - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a camera that aims at downsizing the camera and reducing the number of operating members so that even beginners can use the wide-angle lens well and easily take good pictures with a wide feeling. With the goal. [Structure] In a camera capable of switching focal lengths of two focal points, short focal point and long focal point, when short focal point is selected, the mask 9 covers a part of the photographing screen so that a horizontally long screen size panoramic photographing state is set. Set. [Effect] In the case of short focus, since the mask 9 covers a part of the photographing screen, the effective diameter of the photographing lens is smaller in the short side direction than in the case where the mask 9 is not provided, and the hood and the lens barrel are correspondingly reduced. Can be made smaller.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera having a bifocal variable power optical system, and more particularly to a camera capable of panoramic photography.

[0002]

2. Description of the Related Art Conventionally, the structure of a general bifocal optical system is as follows.
As shown in FIGS. 5A and 5B, the lens group L1 for a short focal length is made movable along the optical axis direction, and when the short focus side is selected, the lens group is moved to the position shown in FIG. 5A. The lens group L
1 is selected and the long focus side is selected, the lens group L1 is moved forward, and another lens group L2, which is a teleconverter retracted from the photographing optical axis, is positioned behind the lens group L1 and the long focus side is selected. Allows for side shooting.

As a camera having such a bifocal optical system, as shown in FIG. 6, an angle-of-view size changeover switch between a short focus (W) and a long focus (T) provided on the front part of the camera body 20. It was done by operating 22.

[0004]

However, in the case of a wide-angle bifocal, for example, 24 mm / 48 mm, the hood and the front lens diameter are large in view of the wide angle of view of 24 mm and the guarantee of the optical performance up to the periphery. Therefore, it has been a major obstacle to downsizing of the lens barrel and downsizing of the entire camera. Moreover, with the wide-angle lens, it is easy for a person to appear small and the sky to appear unnecessarily large.

Further, in recent years, a camera capable of switching between a standard screen and a panoramic screen has been provided. In addition to the bifocal angle-of-view size switch 22 as shown in FIG. 6, a standard screen and a panoramic screen are provided. There is a screen size changeover switch 21 for changing over, and, in general, a panoramic photograph uses a wide-angle lens, and the feature is particularly exerted due to its wide feeling, but the switch for changing the focal length and the screen size There are two changeover switches, which hinders downsizing of the camera and is difficult to operate.

The present invention solves the above-mentioned problems, reduces the size of the camera, and reduces the number of operating members, so that even a beginner can use the wide-angle lens well and can easily take a good photograph with a wide feeling. The purpose is to provide a camera.

[0007]

The structure of a camera that achieves the object of the present invention is as set forth in the appended claims. Specifically, in a bifocal camera, for example, the focal length on the wide-angle side is If the shooting screen size is landscape (1
By setting a panoramic size of 3 mm × 36 mm), the effective diameter of the optical system on the wide-angle side becomes small, so that the hood and the lens barrel can be made smaller accordingly.

Further, since it is not necessary to guarantee the performance up to the periphery of the lens, the design of the optical system is facilitated, the front lens diameter can be reduced, and the overall size of the camera can be reduced.

[0009]

1 to 3 show an embodiment of a camera according to the present invention.

In FIG. 1, 1 is a main photographing lens, 2 is a conversion lens arranged behind the main photographing lens 1 when the long focus side is selected, and 4 is a lens barrel portion for supporting the entire optical system, for example, a camera. When the main switch is turned on, the main photographing lens 1 moves from the retracted position housed in the camera body to a predetermined position in front, and when the long focus side is selected, the teleconverter 3 holding the conversion lens 2 rotates in a known manner. The conversion lens 2 is placed on the photographing optical axis by being rotated by the mechanism. 5 is a hood integrated with the lens barrel 4, 6
Is a light-shielding cylinder provided between the shutter / iris diaphragm 7 and the film 8.

Numeral 9 is a mask for making the photographic screen size a panoramic size, which enters into the light-shielding tube 6 by a well-known means (not shown) to block a part of the optical path at the time of short-focus photography with only the main photographic lens 1. , Which enables panoramic shooting with a horizontally long screen size, and is arranged to retract from the optical path in the light-shielding tube 6 during normal shooting with the conversion lens 2 arranged behind the main shooting lens 1, and these switchings are provided in the camera body. The changeover switch (not shown) is used.

In the above structure, when the short focus side is selected, the panoramic shooting is performed by the mask 9, and when the long focus side is selected, the normal screen size is shot, and the following effects are obtained. .

When the focal length on the short focus side is set to 28 mm, for example, as shown in FIG. 2, assuming a normal screen size in which the horizontally long screen size is not photographed by the mask 9 as in the conventional bifocal camera. While the effective diameter of the taking lens 1 is required to be 6.1 mm on the short side, when the short focus side is selected as in the present embodiment, the horizontally long screen size (1
When panoramic photography of 3 mm × 36 mm) is set, only 5.2 mm is required on the short side.

On the other hand, when the focal length on the long focal length side is set to 48 mm and the screen is not taken in the horizontally long screen size by the mask 9, the effective diameter of the main taking lens 1 is as shown in FIG. The short side requires 5.45 mm.

Therefore, in the conventional bifocal camera in which the laterally long screen size is not set by the mask 9 on the short focus side, the effective diameter of the main taking lens is 6.1 mm on the short side (vertical direction with respect to the taking optical axis). × 2 = 12.2 mm is required.
On the other hand, in the case of the present embodiment, the effective diameter of the main photographing lens 1 is 5.45 mm × 2 = 10.9 mm on the short side, and it is smaller by 12.2 mm-10.9 mm = 1.3 mm on the short side. can do.

Therefore, in this embodiment, the main photographing lens 1 is used.
The effective diameter of the lens itself is the same as the conventional one, and the lens hood and lens barrel on the short side are made smaller by 1.3 mm, so that the lens barrel-related parts can be made smaller than before without affecting shooting. This can contribute to downsizing of the camera.

Further, in the design of the main photographing lens 1, it is not necessary to guarantee the performance up to the peripheral areas which are not used, so that the optical design can be facilitated, the size can be reduced accordingly, and the cost of the glass material can be reduced.

In the above-described embodiments, the main taking lens itself has the same effective diameter as the conventional one, and the lens barrel on the short side is made smaller, but the main taking lens itself has a shorter side direction (shooting optical axis). (Vertical direction with respect to
Can be trimmed to a margin of mm.

Therefore, it is possible to further reduce the size of the lens barrel and the size of the lens hood and the lens barrel-related portion.

In addition, as in the above-described embodiment, when the method of selecting the panoramic photography having the horizontally long screen size is not selected individually but the selection can be made according to the switching of the focal length, the screen size switching operation is performed. The operating member for can also be used as the operating member for selecting two focal points.

FIG. 4 is an external perspective view of an embodiment of a camera provided with such an operating member.

The camera 10 of the present embodiment has three patterns for selecting the photographing state. The first pattern is a non-panorama size long focus (T), and the second pattern is a panorama size long focus (T-). P) and the third pattern is a panoramic size short focus (W-P). Reference numeral 11 denotes a changeover switch for changing over these three patterns, which is arranged on the upper portion of the camera body 10 and displays the above-mentioned three patterns.

Reference numeral 12 is a release button, 13 is a viewfinder, 14 is a strobe, and 15 is a lens barrel. For example, when a power switch (not shown) is turned on, the lens barrel 15 is retracted to a predetermined position as in the above embodiment. Move forward. At that time, when the changeover switch 11 selects the long focus of the non-panorama size which is the first shooting pattern, the conversion lens 2 is arranged behind the main shooting lens 1, but the mask 9 is in the retracted state. . When the panorama size long focus, which is the second shooting pattern, is selected, the combination of the main shooting lens 1 and the conversion lens 2
In addition, the mask 9 has a horizontally long screen size that blocks part of the screen. Further, when the panoramic size short focus, which is the third shooting pattern, is selected, the conversion lens 2 retracts from the rear of the main shooting lens 1 and the mask 9 becomes a horizontally long screen size that blocks part of the screen. I have to.

According to the present embodiment having the above-described structure, the number of shooting patterns increases, and the switching means for selecting panoramic shooting and standard shooting, which are horizontally long screen sizes, and the means for switching between two focal points are separately provided. Therefore, it is possible to reduce the number of operating members, contribute to downsizing, and improve operability.

[0025]

As described above, according to the present invention,
For example, when the wide-angle lens of a bifocal camera is used, by limiting the screen size to the panoramic size of a landscape screen, the camera can be dramatically downsized without sacrificing general usability. Can be obtained.

(1) Since the effective diameter of the lens becomes small,
In the case where the lens hood, the lens barrel, etc. have the focal length as in the embodiment, for example, it becomes about 10% smaller. That is, the lens barrel-related portion becomes smaller, the overall size of the camera can be reduced, and portability is improved.

(2) In the wide-angle lens design, it is not necessary to guarantee performance up to the periphery of the lens, and it is possible to achieve miniaturization or cost reduction of glass material commensurate with it.

(3) Even for beginners, when framing a wide-angle panorama, the main subject does not become small and the sky or the like is not reflected more than necessary, so it is easy to frame and not get a distracting impression.

(4) The screen size and focal length can be easily switched by operating one operating member.

[Brief description of drawings]

FIG. 1 is a sectional view of a camera showing an embodiment of the present invention.

FIG. 2 is a diagram showing an effective diameter of a main photographing lens at the time of short focus.

FIG. 3 is a diagram showing an effective diameter of a main photographing lens at the time of long focus.

FIG. 4 is an external perspective view of a camera according to another embodiment of the present invention.

FIG. 5 is a diagram showing a conventional bifocal optical system.

FIG. 6 is an external perspective view of a conventional bifocal camera.

[Explanation of symbols]

 1 Main photography lens 2 Conversion lens 6 Light-shielding tube 9 Mask 11 Changeover switch

Claims (4)

[Claims] 1. An optical system having a plurality of focal lengths can be selected,
In addition, in a camera capable of changing the shooting screen size into at least two types, the shooting screen size at that time is fixed to either one when an optical system with at least one focal length is selected. Characteristic camera. 2. The camera according to claim 1, wherein the shooting screen size fixed when an optical system having at least one focal length is selected is a horizontally long screen size. 3. The camera according to claim 2, wherein a focal length on which a horizontally long screen size image pickup screen is fixed is on the short focus side. 4. A camera according to claim 1, 2 or 3, wherein switching of a photographing screen and switching of a focal length are performed by one operating member.