JPH0772530A - Optical finder - Google Patents

Abstract

PURPOSE:To prevent dust from entering a space between prisms from the outside and to obtain an excellent object image at an ocular part by housing plural prisms constituting an optical finder in a case through a sealing member and hermetically sealing the space between the prisms by the sealing member. CONSTITUTION:The 1st prism 242 is housed in a prism frame 243 through a rubber packing 260. The 2nd prism 246 is housed in the prism frame 248 through the rubber packing 262. Since the space between the prisms surrounded by a finder main body 202 and the prisms 242 and 246 can be hermetically sealed by the packings 260 and 262, the dust does not enter this space from the outside. Therefore, the excellent object image is obtained because the dust does not adhere to the prisms 242 and 246.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical viewfinder, and more particularly to a compact camera or a simple type camera-integrated VT.
It relates to an optical finder applied to R.

[0002]

2. Description of the Related Art Conventionally, in this type of optical finder, an objective lens, a plurality of prisms, and an eyepiece lens are arranged in a case, and light of a subject image emitted from the objective lens is refracted by the plurality of prisms. , There is a system in which a subject image is guided to an eyepiece lens.

[0003]

However, in the conventional optical viewfinder, since dust enters between the prisms and minute dust and the like can be seen at the eyepiece in addition to the subject image, a good subject image cannot be obtained. There is a drawback that. The present invention has been made in view of such circumstances, and an object thereof is to provide an optical finder capable of obtaining a good subject image.

[0004]

In order to achieve the above object, the present invention provides an optical finder that refracts light by a plurality of prisms housed in a case and guides a subject image to an eyepiece of a camera. The plurality of prisms are housed in the case via a seal member, and the space between the plurality of prisms is sealed by the seal member.

[0005]

According to the present invention, a plurality of prisms are respectively housed in the case via the seal members, the space between the prisms surrounded by the case and the prisms is sealed by the seal member, and the space between the prisms is externally exposed. Dust is prevented from entering from. As a result, dust is not attached to the prism, and a good subject image can be obtained.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the optical finder according to the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 shows a camera-integrated VTR 1 to which an optical finder according to the present invention is applied.
It is a perspective view which shows the external appearance of 0. This camera integrated VTR
10 includes a camera unit 12 and a VTR deck unit 14, and the camera unit 12 includes a zoom lens device 16 and an optical finder 200. The VTR deck unit 14 includes a video cassette tape loading device and the like. It is provided.

FIG. 2 is a perspective view showing the outline of the camera unit 12 excluding the outer case, and FIG. 3 is a front view of the zoom lens device 16 and the optical finder 200 taken along line 3-3 in FIG. 4 is a sectional view taken along line 4-4 in FIG. 5 and 6 are exploded perspective views of the front half and the rear half of the zoom lens device 16. The zoom lens device 16 and the optical finder 200 are arranged in parallel in a case 18 shown in FIGS. 2 and 3, and the zoom lens device 16 includes a front frame 20, a fixed frame 22, and a first frame as shown in FIGS. The movable frame 24, the iris unit 26, and the second movable frame 28 are main components. A CCD unit 30 is attached to the rear part of the case 18 corresponding to the zoom lens device 16.
A side cam barrel 32, which will be described later, is arranged in parallel with the photographing optical axis 34 on the side of the zoom lens optical system of the case 18.

As shown in FIG. 5, a protective glass 36 is attached to the opening 20A of the front frame 20, and the front frame 20 has a claw portion 38 formed on the upper portion thereof for the first moving frame 24. By being locked in the hole 40 of the first moving frame 24
Fixed to. The fixed frame 22 is a front edge 1 of the case 18.
9 is fixed by screws 42, 42. On the other hand, three taking lenses 44, 46, and 48 are fixed to the first moving frame 24 via a lens frame 50. The iris unit 26 is fixed to the front side of the second moving frame 28 with screws 52, 52, and the iris meter 27 of the iris unit 26 is inserted into the opening 27A of the second moving frame 28.

Further, three lenses 54, 56 and 58 are attached to the second moving frame 28 via a spacing ring 60 and a stopper ring 62. In the case 18, five guide rods 64, 66, 68, 7 are arranged in parallel with the photographing optical axis 34.
0 and 72 are arranged, and the front ends of the guide rods 64 to 72 are
The rear end is press-fitted and fixed in the holes formed in the fixed frame 22, and the rear end is press-fitted and fixed in holes (not shown) formed in the rear wall of the case 18.

In the first moving frame 24, the guide rod 66 is inserted through the guide holes 74, 74 formed in the upper portion of the first moving frame 24, and the guide rod 72 is positioned in the steady rest groove 76. , 72, and can be moved back and forth. Further, the guide rod 68 is inserted into the guide hole 82 of the connecting piece 80, which will be described later, and the guide rod 64 is positioned in the steady rest groove 84 of the connecting piece 80.

In the second moving frame 28, the guide rod 64 is inserted into the pair of guide holes 88, 88, and the guide rod 72 is positioned in the steady rest groove 90.
It can be moved back and forth by being guided by the guide rods 64 and 72. On the other hand, the side cam barrel 32 shown in FIG. 6 is arranged laterally of the first moving frame 24 and the second moving frame 28.
A shaft 92 is inserted and fixed in the side cam barrel 32. The front end 94 of the shaft 92 is pivotally supported in the hole 96 of the fixed frame 22 as shown in FIG.
The shaft 8 is pivotally supported by the hole 100 of the case 18 as shown in FIG.

A gear 110 is formed integrally with the shaft 92, and the gear 110 is meshed with a gear 114 of a motor 112 which will be described later. Therefore, the side cam barrel 32 is rotated by transmitting the driving force from the motor 112 via the gears 114 and 110. As shown in FIG. 6, four cam grooves 116, 118, 12 are provided on the outer peripheral surface of the side cam barrel 32.
0, 122 are formed. A cam 124 is formed at the rear edge of the side cam barrel 32, and the cam 124 is engaged with an end 128 of a display plate 126 (see FIG. 3) described later.

The cam 116 has a connecting piece 80 shown in FIG.
Driven pin 130 is inserted. The connection piece 80 is
The upper end 80 </ b> A of the connecting piece 80 is connected to the projecting piece 25 fixed to the first moving frame 24 via the extension spring 86, and the upper end 80 </ b> A of the connecting piece 80 is moved by the urging force of the extension spring 86.
Is pressed against the front side portion 78 of the. As a result, the first moving frame 24 moves the optical axis 34 by the urging force of the tension spring 86.
Is urged toward the front of. In addition, the tension spring 8
No. 6 has a spring force that allows the first moving frame 24 to escape to the camera rear side with respect to the connecting piece 80 when an external force is applied to the first moving frame 24.

A driven pin 132 of the second moving frame 28 shown in FIG. 6 is fitted into the cam 118. Therefore, when the side cam barrel 32 is rotated, the first moving frame 24 and the second moving frame 28 move toward each other along the cams 116 and 118 on the photographing optical axis 34 (tele side direction) and away from each other (telephoto side direction). It is possible to move back and forth in the wide side direction). As a result, the photographing magnification of the subject image can be changed.

As shown in FIGS. 2 and 7, the optical viewfinder 2
The finder body 202 of 00 has side openings 206 (see FIG. 6) of the case 18 by screws 204, 204.
Fixed to. In addition, the finder body 202,
A fixed frame 208, a front moving frame 210, a rear moving frame 212, a display plate 126, and a plurality of prisms described later are held.

The finder body 202 includes a guide plate 21.
The front moving frame 210 and the rear moving frame 212 are arranged on the finder optical axis 216 on the guide plate 214. Further, the front moving frame 210 and the rear moving frame 212 are provided with guide pins 2 fixed to the side surfaces thereof.
By fitting 18 and 220 into the straight groove 222 formed in the side surface of the guide plate 214, the straight groove 222 can be moved back and forth along the straight groove 222.

The front moving frame 210 has a variable power lens 224.
Further, three correction lenses 226, 228 and 230 are attached to the rear moving frame 212. The lens 228 has a rectangular surface, and two spacing pins 232, 232 ... Are integrally formed with the lens 228 at the corners thereof. These pins 232, 2
32 are correction lenses 226, 22 on the rear moving frame 212.
When the 8 and 230 are assembled, they come into contact with the corners of the lenses 226 and 230 to serve as a spacing ring.

The front moving frame 210 and the rear moving frame 21 are also provided.
The driven pins 234 and 236 of the second are the side cam barrels 32.
It is fitted in the cam grooves 120 and 122 formed in the.
As a result, the front moving frame 210 and the rear moving frame 212 are rotated by rotating the side cam barrel 32.
It moves back and forth along the cam grooves 120 and 122 on the image pickup unit 16, and forms a subject image of approximately the same magnification as the subject image scaled by the first moving frame 24 and the second moving frame 28 on the eyepiece.

On the other hand, the display plate 126 is fixed to the guide rod 238 and arranged behind the rear moving frame 212. The guide rod 238 is pivotally supported on the finder body 202. As a result, the display plate 126 is rotatable together with the guide rod 238. In addition, the fixed frame 208 includes the screw 2
It is fixed to the front surface of the guide plate 214 by 40 and 240.

On the other hand, a first prism 242 is provided behind the rear moving frame 212 as shown in FIG.
As shown in FIG. 8, the prism 242 is stored in a prism frame 243 via a rubber packing 260. As a result, the light incident from the front surface of the first prism 242 is refracted by 90 ° by the first prism 242 and is emitted upward. A field frame 244 is provided at a position where the emitted light forms an image.

A second prism 246 is provided above the field frame 244, and the second prism 246 is housed in the prism frame 248 via a rubber packing 262. As a result, the light incident from the bottom surface of the second prism 246 is refracted by 90 ° by the second prism 462 and is emitted toward the rear eyepiece. As shown in FIG. 9, the packing 260, 262 seals the space 264 between the prisms surrounded by the finder body 202 and the prisms 242, 246.

A spacer 250 is provided behind the second prism 246, and the light refracted by the second prism 250 is emitted toward the eyepiece 252 shown in FIG. 4 via the spacer 250. It Next, the operations of the zoom lens device and the optical finder configured as described above will be described.

First, the motor 112 is driven to rotate normally,
When the side cam barrel 32 shown in FIG. 6 is rotated in the clockwise direction (wide side direction), the first moving frame 24 pulls the tension spring 86.
The second moving frame 28 moves toward the front of the photographing optical axis 34 together with the connecting piece 80, and the second moving frame 28 moves toward the rear of the photographing optical axis 34 along the cam 118. Thereby, the photographing magnification can be changed to the wide side. Also, the first
In conjunction with the movement of the moving frame 24 and the second moving frame 28, the front moving frame 210 and the rear moving frame 212 of the optical finder 200 are moved back and forth on the finder optical axis 216 along the cam grooves 120 and 122 of the side cam barrel 32. The object image is moved and formed on the eyepiece section 252 of the finder at a magnification of the zoom lens optical system and a subject image having substantially the same magnification.

Next, the motor 112 is reversely driven, and the motor shown in FIG.
When the side cam barrel 32 shown in FIG. 6 is rotated counterclockwise (tele side direction), the first moving frame 24 is pushed by the connecting piece 80 and moves toward the rear of the photographing optical axis 34, and the second moving frame 28. Moves along the cam 118 toward the front of the photographing optical axis 34. Thereby, the photographing magnification can be changed to the tele side. The front moving frame 21 is linked with the movement of the first moving frame 24 and the second moving frame 28 of the optical finder 200.
0 and the rear moving frame 212 move back and forth along the cams 120 and 122 on the finder optical axis 216, and the object image of a magnification substantially equal to the magnification changed by the zoom lens optical system is displayed on the eyepiece 252 of the finder. To form.

On the other hand, in the optical finder 200 of this embodiment, as shown in FIG. 9, a space 264 between the prisms surrounded by the finder body 202 and the prisms 242 and 246 is sealed by packings 260 and 262, and this space 26
Dust is prevented from entering the inside of the unit 4. Accordingly, in the optical finder 200 of the present embodiment, dust does not adhere to the prisms 242 and 246, so that a good subject image can be obtained.

FIG. 10 is an enlarged view of the essential parts showing a second embodiment of the optical finder according to the present invention. In this second embodiment, the space 264 between the prisms 242 and 246 is sealed with a shield agent 266. There is. In this way, the packing 26
The same effect can be obtained by using the shield agent 266 instead of 0 and 262.

Further, in this embodiment, two prisms 24 are used.
Although the optical finder 200 using 2,246 has been described, it is also applicable to an optical finder using three or more prisms. Furthermore, although the optical finder 200 having a lens is described in the present embodiment, the present invention can be applied to a perspective finder having no lens.

[0028]

As described above, according to the optical finder of the present invention, the plurality of prisms are housed in the case via the seal members, and the space between the prisms is sealed by the seal member. It is possible to obtain a good subject image because dust from the inside is prevented from adhering to the prism.

[Brief description of drawings]

FIG. 1 is a perspective view of a camera-integrated VTR to which an optical finder according to the present invention is applied.

FIG. 2 is a perspective view of a camera unit applied to the optical finder according to the present invention.

FIG. 3 is a front view of the zoom lens device and the optical viewfinder taken along line 3-3 in FIG.

4 is a cross-sectional view of the zoom lens device and the optical viewfinder taken along line 4-4 in FIG.

FIG. 5 is an assembled perspective view of the zoom lens device including a first moving frame.

FIG. 6 is an assembled perspective view including a second moving frame of the zoom lens device.

FIG. 7 is an assembled perspective view of an optical finder.

FIG. 8 is an enlarged view of a main part of the optical finder according to the present invention.

FIG. 9 is a cross-sectional view showing a first embodiment of a prism mounting state.

FIG. 10 is a cross-sectional view showing a second embodiment of a prism mounted state.

[Explanation of symbols]

 10 ... Camera integrated VTR 16 ... Zoom lens device 200 ... Optical finder 202 ... Finder body 242, 246 ... Prism 260, 262 ... Packing 266 ... Shielding agent

Claims (1)

[Claims] 1. An optical finder that refracts light by a plurality of prisms housed in a case and guides a subject image to an eyepiece section of a camera, wherein the plurality of prisms are inside the case via a seal member. The optical finder, which is housed in, and wherein the space between the plurality of prisms is sealed by the sealing member.