JPH09236894A - Structure for flare prevention frame - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a clear printed photograph by preventing flare from occurring. SOLUTION: A flare prevention frame on a main body side 35 cutting incident light advancing to the outside of a standard exposure range 30 and preventing the flare from occurring is arranged at a position near to an aperture 32. A flare prevention frame on a black box side 37 is arranged at a position near to a photographing lens 8. By the frame 37, the incident light advancing to the outside of the range 30 is cut and one part of the incident light entering a photographing optical path and advancing to a circumferential edge part 30a between an exposure range for printing 31 and the range 30 is also cut. Besides, the light causing the flare is cut by the frame 37 by as much as it enters the photographing optical path. Then, the circumferential edge part 30a becomes under exposure but it does not appear on the printed photograph because it is covered with a ask at a printing time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a flare preventive frame, and more particularly to a structure of a flare preventive frame for cutting off incident light from a taking lens which goes out of an exposure range to prevent flare from occurring. is there.

[0002]

2. Description of the Related Art When an image is taken with a camera, incident light from a taking lens is reflected by a lens surface, a lens barrel, an inner wall surface of a camera body, etc., and a part of an image (exposure range) of a photo film is taken. Alternatively, stray light is applied to the entire surface to cause flare that lowers the contrast of the image formed on the photographic film. To prevent this flare, for example, in a lens-fitted photo film unit with a pre-loaded unexposed photo film in the unit body with a simple shooting mechanism, the diaphragm aperture and the photo film placed behind the shooting lens are A flare prevention frame is placed between the aperture and the aperture.

The flare prevention frame has an opening similar in shape to the aperture. By cutting off the incident light that is incident on the outside of the photographic screen out of the incident light that has entered from the aperture opening, the incident light is opened. The amount of flare generated is reduced by preventing the photographic film from being exposed by the reflected light reflected by the inner surface of a dark box or the like that shields between the aperture and the aperture.

[0004]

However, despite the provision of the flare prevention frame as described above, a sufficient effect of preventing flare is not obtained, and the contrast of the photographed image is sufficiently good. I couldn't say that it was in such a state.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a structure of a flare prevention frame capable of more effectively preventing flare.

[0006]

In order to achieve the above object, the present invention has a structure of a flare preventive frame according to claim 1, wherein an aperture for defining an exposure range of a photographic film to a predetermined size and a photographing lens are provided. And is directed toward the optical axis of the taking lens so as to block a part of the incident light from the taking lens that forms an image outside the printing range set inside the exposure range defined by the aperture. And has an opening that is substantially similar to the aperture.

Further, in the structure of the flare prevention frame according to the second aspect, between the aperture for defining the exposure range of the photographic film to a predetermined size and the photographing lens, the outside of the exposure range defined by the aperture is directed. First and second flare prevention frames are provided which project toward the optical axis of the taking lens so as to block the incident light from the taking lens and form an opening substantially similar to the aperture. At least one flare prevention frame of the first and second flare prevention frames forms an image of the incident light from the photographing lens that forms an image outside the print range set inside the exposure range defined by the aperture. It is configured so as to project toward the optical axis of the taking lens so as to block a part.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 2 showing the outer appearance of a lens-fitted photo film unit embodying the present invention, the lens-fitted photo film unit 2 comprises a unit main body 3 incorporating a photographic film cartridge and various photographing mechanisms, and an exterior enclosing the same. It is composed of the body 4. The exterior body 4 has a contour that exposes the winding knob 5, the shutter button 6, the stroboscopic light emitting portion 7 and the like of the unit main body 3, and exposes the taking lens 8, the viewfinder 9, the shot number display window 10 and the like. A hole is provided so that the photographing operation can be performed with the exterior body 4 wrapped around the unit body 3.

As shown in FIG. 3, the unit main body 3 is composed of a main body base 12, a rear cover 13, an exposure unit 14, a strobe unit 15, and a front cover 16. The rear cover 13 is attached to the back of the main body base 12 so that the rear cover 13 and the main body base 12 are attached to each other.
Store 8 in a light-tight manner. The front cover 16 is detachably attached to the front surface of the main body base 12. On the upper surface of the front cover 16, there is provided a shutter button 6 which is partially notched and is elastically formed. By pressing the shutter button 6, an image can be taken.

In the main body base 12, a cartridge storage chamber 22 for storing the cartridge 21 of the photographic film cartridge 18 and a film roll 23a in the form of a roll of the unexposed photographic film 23 pulled out from the cartridge 21 are stored. And a film roll chamber 24 for forming the film are integrally formed. The bottom surfaces of the cartridge storage chamber 22 and the film roll chamber 24 are openings, and after the photographic film cartridge 18 is loaded, the rear cover 1
It is closed by the bottom lids 25 and 26 provided in 3.

The winding knob 5 is provided in the cartridge storage chamber 2
The rear cover 13 is rotatably arranged on the upper surface of
Is exposed to the outside of the unit main body 3, and the spool 27 of the cartridge 21 is rotated in the film winding direction by rotating the exposed portion in the forward rotation direction (counterclockwise direction in FIG. 3). The photographed film 23 that has been taken is stored in the cartridge 21.

The photographic film cartridge 18 has been proposed in the technical field and introduced in the monthly magazine "Photo Industry" (Photo Industry Co., Ltd., December 1994, p.11), APS (A
dvanced Photo System), cartridge 2
1 is made of plastic, and is disclosed in JP-A-6-266053.
There is a built-in film feeding mechanism as known from Japanese Patent Publication No. The cartridge 21 stores the photographic film 23 inside when not in use, and sends the photographic film 23 out by rotating the spool 27 when in use. Further, a lid member that is rotated to shield the inside of the cartridge 21 from light is incorporated in a film entrance / exit through which the photographic film 23 is drawn out.

As shown in FIG. 4, two kinds of perforations 23b and 23c of a large size and a small size are formed on the photographic film 23 at a predetermined pitch, and a two-tooth sprocket 29 (see FIG. 5) incorporated in the exposure unit 14 is provided. In response to engaging these, the film winding stop mechanism operates to lock the winding knob 5. Shutter charging is performed in association with the film feeding during this period. Shooting is performed by the shutter release operation, and thereafter, by repeating this, shooting is sequentially performed from the rear end side (the side locked by the spool 27) of the photo film 23 toward the front end side. . Large and small 2 lined up at short intervals
1 based on individual perforations 23c and 23b
Although frame advance control is performed, it is determined that the actual photographed frame is exposed at a position aligned with the long interval of the perforations 23b and 23c.

The size of the standard exposure range (hereinafter referred to as the standard exposure range) 30 of the photographic film 23 of the photographic film 23 is 16.7 mm × 30.2 mm (high-definition size). In the unit 2, a range (hereinafter referred to as a print range) 31 that is smaller than the standard exposure range 30 and is actually printed by a dark box side flare prevention frame 37 described later is called a print range 31.
More than that, the exposure amount of the peripheral edge portion 30a indicated by hatching in the drawing becomes smaller.

As shown in FIGS. 3 and 5, the main body base 12
On the optical axis 8a of the taking lens 8 at the center of the, an aperture 32 is formed which defines the exposure range on the photographic film 23 to the size of the standard exposure range 30. This aperture 3
The rear side of 2 is formed into a curved shape protruding to the rear side of the unit main body 3 in order to support the photographic film 23 in a shape that matches the field curvature of the taking lens 8, and the aperture of the rear cover 13 is matched with this. The portion facing 32 is also curved.

An engagement wall 34 on the frame to which the dark box 33 is attached is formed on the outer periphery of the front side of the aperture 32. The engagement wall 34 has a shape that projects toward the front. The inner wall of the front surface of the engagement wall 34 blocks incident light that goes outside the standard exposure range 30 of the photographic film 23 and prevents flare from occurring. The main body side flare prevention frame 35 is integrally formed. The main body side flare prevention frame 35 is projected from the engagement wall 34 toward the optical axis 8a of the photographing lens 8 so as to cut only the incident light from the photographing lens 8 toward the outside of the photographing screen 30. , An opening 35a similar to the aperture 32 is formed.

The exposure unit 14 includes a base member 36,
A shutter mechanism assembled to the base member 36, a film winding stop mechanism, an optical system of the finder 9, and the like,
The dark box 33 is integrally provided under the base member 36 and surrounds the photographing optical path in a cylindrical shape. Also, this dark box 33
A dark box side flare prevention frame 37 for more effectively reducing the occurrence of flare is assembled inside the.

As shown in FIG. 1, the exposure unit 14 includes
The dark box 33 formed integrally with the base member 36 is attached to the engagement wall 34 formed on the front surface of the main body base 12 and mounted on the main body base 12. On the back side of the dark box 33, a ridge 33a is formed on the entire circumference, and the ridge 33a enters into the groove 34a formed on the end face of the engaging wall 34 so that the ridge 33a is incident from the taking lens 8 and photographed. The shooting optical path of the incident light toward the film 23 is blocked.

The taking lens 8 is mounted on the front surface of the dark box 33. The taking lens 8 includes a lens substrate 8a and two lenses 8b and 8c incorporated in the lens substrate 8a.
And a lens holding frame (not shown) that covers the front surface of the lens substrate 8a and prevents the lenses 8b and 8c from falling off from the lens substrate 8a. A diaphragm opening 38 is formed on the rear surface of the lens substrate 8a, and behind the diaphragm opening 38, shutter blades 39 that are rotated in response to a pressing operation of the shutter button 6 are arranged. An exposure opening 40 is formed in the front surface of the dark box 33 that faces the aperture 38 with the shutter blade 39 interposed therebetween. The exposure opening 40 is opened and closed by rotating the shutter blade 39.

The dark box side flare prevention frame 37 is provided with an aperture 3
It is a frame-shaped member having an opening 37a having a shape substantially similar to that of 2, and is assembled in the dark box 33 by welding, caulking or the like. As a result, when the dark box 33 is attached to the engagement wall 34 of the main body base 12, the dark box side flare prevention frame 37 is provided between the main body side flare prevention frame 35 and the exposure opening 40.
3 are arranged so as to project into the inside.

In this way, the flare preventing frame 35 on the main body side is appropriately spaced between the taking lens 8 and the photographic film 23.
By providing the dark box side flare prevention frame 37, incident light that enters the photographing lens 8 and goes out of the standard exposure range 30 from the photographing lens 8 is cut by the main body side flare prevention frame 35 and the dark box side flare prevention frame 37. , Dark box 33 or engaging wall 3
The reflected light, which is the incident light reflected on the inner surface of 4, is the photographic film 23.
Therefore, the amount of flare generated is effectively reduced as compared with the case where only one flare prevention frame is provided. The inner surfaces of the dark box 33 and the engagement wall 34 are configured to reduce the reflection of light that has not been cut by the flare prevention frames 35 and 37 due to graining or the like.

By the way, when making a print photograph from a developed photographic film, a mask is applied to the photographic film, and the area within the opening of the mask is printed on the photographic paper as the print area. Generally, the opening of this mask has a size smaller than the range exposed on the photographic film as an image frame. For this reason,
In the created print photograph, the peripheral portion 30a of the standard exposure range 30 is not printed, and only the print range 31 is printed. Therefore, in the present invention, paying attention to the fact that the peripheral portion 30a is not printed, the dark box side flare prevention frame 37 is arranged so as to cut a part of the incident light to be exposed on the peripheral portion 30a which is not printed on the photographic film 23. The amount of flare generated is more effectively reduced by projecting extra.

The dark box flare prevention frame 37 has a standard exposure range 30 of the incident light that is emitted from the aperture 38 of the taking lens 8 and enters the dark box 33 at the position where the frame 37 is attached.
Of the dark box by cutting off the incident light toward the outside of the photo-taking path and also cutting off part of the incident light entering the photographing optical path toward the peripheral edge portion 30a between the printing exposure range 31 and the standard exposure range 30. The photographing lens 8 from the inner surface of 33
Projected toward the optical axis 8a. That is, the dark box side flare prevention frame 37 has an opening 37a having a size smaller than the opening of the flare prevention frame that regulates the incident light from the taking lens 8 in the size of the standard exposure range 30 at the arranged position. .

In this way, the dark box side flare prevention frame 37
By entering into the shooting optical path, the amount of incident light from the shooting lens 8 unrelated to shooting is cut by the extra amount, and the amount of flare generated is further reduced.

The dark box side flare prevention frame 37 cuts off a part of the incident light traveling toward the peripheral edge portion 30a of the standard exposure range 30 in addition to the incident light which causes flare.
The peripheral portion 30a has a smaller amount of exposure than the print range 31 and is underexposed, but the peripheral portion 30a that is underexposed is adjusted by adjusting the length of the dark box side flare prevention frame 37 entering the photographing optical path. The print range 31 printed on the print photograph is prevented from entering. Therefore, there is no hindrance in the actual production of the print photograph, and even if the mask is slightly displaced, the peripheral edge portion 30a is exposed, so that a black edge does not occur in the print photograph.

Next, the operation of the above configuration will be described.
At the time of shooting, the winding knob 5 is rotated to feed the photographic film 23 by one frame. By this one frame advance,
The unexposed portion of the photographic film 23 is set behind the aperture 32, and shutter charging is performed. After that, when the shutter button 6 is pressed, the shutter mechanism is operated, the shutter blade 39 is rotated, and the exposure opening 40 on the front surface of the dark box 33 is opened and closed.

By rotating the shutter blade 39, the exposure opening 4 is opened.
While 0 is open, the lenses 8b, 8 of the taking lens 8 are
The light emitted from the aperture opening 38 through c is the dark box 33.
The light enters the dark box 33 through the exposure opening 40 of the. At this time, most of the incident light entering from the aperture opening 38 from the outside of the photographing range corresponding to the standard exposure range 30 and going to the outside of the standard exposure range 30 is generated by the dark box side flare prevention frame 37. It is cut by any of the body side flare prevention frames 35. As a result, most of the incident light that is reflected by the inner surfaces of the dark box 33 and the engagement wall 34 and exposes the photographic film 22 unrelated to the shooting is cut, and the amount of flare generated is reduced.

The dark box side flare prevention frame 37 is additionally provided in the photographing optical path so as to cut off a part of the incident light incident on the dark box 33 from the photographing lens 8 in the print range 31 smaller than the standard exposure range 30. Since it is designed to go in, much of the incident light that has nothing to do with shooting is cut. Therefore, the amount of flare generated is smaller than in the case where two flare prevention frames that define the incident light in the standard exposure range 30 are provided.

On the other hand, the incident light in the photographing range, which has entered the dark box 33 through the aperture 38, exposes the standard exposure range 30 of the photographic film 23 through the aperture 32. At this time, the incident light that forms an image within the print range 31 of the photographic film 23 reaches the photographic film 23 through the openings 37a and 35a without being cut by the flare prevention frames 37 and 35, and enters the photographic film 23. Photo film 23 with total light intensity
The print range 31 of is exposed. Further, the incident light imaged at the peripheral edge portion 30 a between the print area 31 and the standard exposure area 30 of the photographic film 23 is dark box side flare prevention frame 3.
Since a part of it is cut at 7, the peripheral portion 30a is exposed with the remaining incident light amount that has not been cut. As a result, the peripheral portion 30a is underexposed to some extent as compared with the print range 31.

As described above, the winding operation of the winding knob 5 and the pressing operation of the shutter button 6 are alternately repeated to sequentially photograph each frame of the photographic film 23. And after the shooting of all the frames is completed,
The photo film 23 is rotated by continuously rotating the winding knob 5.
Are stored in the cartridge 21, and the whole film unit with lens 2 is submitted to a developing place or DPE.

At a developing station or the like, the bottom lid 25 of the unit main body 3
Is opened to take out the photographed photo film cartridge 18 from the unit main body 3, the photo film 23 is pulled out from the cartridge 21, and a developing process and a printing process are performed. In the print process, the images of the photographed frames of the developed photographic film 23 are printed on photographic paper. At this time,
For each frame, clean the edges around the image of the printed photo, or the photo film 23 where the image is not exposed.
In order to prevent the contrast of the image of the printed photograph from being deteriorated by the influence of the strong light transmitted through the film base of H.V., a mask for high-definition having an opening size smaller than the standard exposure range 30 is applied, and the mask opening Only the image exposed in the print area 31 inside is printed on the printing paper.

As a result, as shown in an example in FIG. 6, only the image in the print range 31 of the standard exposure range 30 of the photographed frame 50 exposed as shown in FIG. 6A is printed on the photographic paper. A print photograph 51 as shown in FIG. 6B is created, and the image of the peripheral edge portion 30 a outside the print range 31 is not printed on the print photograph 51. Therefore, the image of the peripheral portion 30a which is underexposed as compared with the print range 31 does not appear in the print photograph 50. Of course, the opening of the mask is the photo film 23.
The image of the peripheral edge portion 30a appears in the print photograph 51 when it deviates from the print range 31 of 1. However, since the image of the peripheral edge portion 30a is slightly underexposed, there is no practical problem. Since the printed photograph 51 is made from the photographic film 23 which is exposed by the main body side flare prevention frame 35 and the dark box side flare prevention frame 37 with the flare generation amount being extremely reduced as described above, A good and clear image is recorded. Of course, it is needless to say that a print photograph of a size other than the high-definition size can be created from this photo film 23.

In the above description, the dark box flare prevention frame 37 cuts off a part of the incident light reaching the outside of the print range 31, but the dark box flare prevention frame 37 partially absorbs the incident light. It is sufficient that the range for cutting is larger than the print range 31 and inside the standard exposure range 30. For example, by cutting off a part of the incident light that reaches the outside of the print range 31 that is slightly larger than the print range 31, it is possible to eliminate the influence of the difference in the size of the mask opening caused by the difference in the print processing apparatus.

Also, an example has been described in which only the dark box side flare prevention frame 37 is excessively projected so that a part of the incident light reaching the outside of the print range 30 is cut by the dark box side flare prevention frame 37. , Dark box side flare prevention frame 37
Instead of this, a part of the incident light reaching the outside of the print range 31 may be cut by the main body side flare prevention frame 35 near the aperture 32. Even in this case, the amount of flare generated can be reduced. There is. Further, both the dark box side flare prevention frame 37 and the main body side flare prevention frame 35 may be projected so as to cut a part of the incident light reaching the outside of the print range 31. In this way, by increasing the protruding lengths of both the dark box side flare prevention frame 37 and the main body side flare prevention frame 35, the amount of flare generated can be reduced more effectively than in the case of only one. .

In the above embodiment, the example in which the dark box side flare prevention frame and the main body side flare prevention frame are provided between the taking lens and the aperture has been described, but one flare prevention frame is provided between them. Even in this case, if the flare prevention frame cuts off a part of the incident light reaching the outside of the print range, the amount of flare generated can be reduced. Of course, even when two or more flare prevention frames are provided, it is possible to reduce the flare generation amount by increasing the protruding length of one or more of the flare prevention frames. is there.

In the above-mentioned embodiment, the case of exposing to the size of the standard exposure range using the APS photographic film has been described, but the present invention can be used even in the case of the exposure range of various aspect ratios. You can further,
A 135-type photographic film may be used, and it can be used not only for a lens-fitted film unit having a built-in film in advance, but also for a general camera.

[0037]

As described above, according to the present invention, it is possible to obtain an image from a photographing lens which forms an image outside the print range printed when printing is set inside the exposure range defined by the aperture. Part of the incident light is blocked and projected toward the optical axis of the shooting lens,
Since the flare prevention frame having an opening that is almost similar to the aperture is provided between the aperture and the shooting lens, a large amount of light unrelated to shooting can be blocked by the extra protrusion of the flare prevention frame. The amount generated can be extremely reduced. At the time of printing, only the print area is printed, so the part where the incident light is partially blocked and the underexposure is not printed on the print, and the amount of flare generated is extremely low. Can be created.

Further, between the aperture and the taking lens, two flares projecting toward the optical axis of the taking lens are arranged so as to block the incident light from the taking lens which goes to the outside of the exposure range defined by the aperture. The amount of flare generated can be reduced by blocking part of the incident light from the shooting lens that forms an image outside the print range set inside the exposure range for either or both of the prevention frames. It is possible to make it extremely small, and it is possible to produce a good print photograph with extremely small amount of flare generated. If both flare prevention frames are designed to block a part of the incident light from the photographing lens that forms an image outside the print range, the amount of flare generated can be further reduced.

[Brief description of drawings]

FIG. 1 is an explanatory diagram illustrating the operation of a dark box side flare prevention frame and a body side flare prevention frame according to the present invention.

FIG. 2 is a perspective view showing an external appearance of a lens-fitted film unit provided with a dark box side flare prevention frame and a main body side flare prevention frame.

FIG. 3 is an exploded perspective view showing the lens-fitted film unit in an exploded manner.

FIG. 4 is an explanatory diagram showing a range exposed on a photographic film.

FIG. 5 is a perspective view showing the back side of the aperture.

FIG. 6 is an explanatory view showing an exposed photographic film and a print photograph obtained from this photographic film.

[Explanation of symbols]

 8 Photographic lens 23 Photo film 32 Aperture 30 Standard exposure range 30a Edge 31 Print range 33 Dark box 35 Body side flare prevention frame 35a Open 37 Dark box side flare prevention frame 37a Open

Claims (2)

[Claims] 1. An image is formed between an aperture that defines an exposure range of a photographic film to a predetermined size and a photographing lens, and an image is formed outside a print range that is set inside the exposure range defined by the aperture. A structure of a flare prevention frame, characterized in that it has an opening that is projected toward the optical axis of the taking lens so as to block a part of the incident light from the taking lens, and has a similar shape to the aperture. 2. Between the aperture that defines the exposure range of the photographic film to a predetermined size and the taking lens, the incident light from the taking lens that goes outside the exposure range defined by the aperture is blocked. First and second flare prevention frames are provided which project toward the optical axis of the taking lens and form an opening substantially similar to the aperture,
At least one of the first and second flare prevention frames receives light from the photographing lens, which forms an image outside the print range set inside the exposure range defined by the aperture. A structure of a flare prevention frame, characterized in that it projects toward the optical axis of the taking lens so as to block a part of light.