JPH0667352A - Film unit provided with lens - Google Patents

Abstract

PURPOSE:To easily and surely obtain WV(wide) printing which is excellent in aspect ratio at a low cost, and to take a picture having a feeling of powerfulness which is suitable to the WV printing. CONSTITUTION:An aperture 20 is formed to be 20.5mm(X)36mm so that the aspect ratio is about 1.78. Since the image-formation surface of a photographing lens which is a single lens made of plastic is curved, a film path is curved along it. The photographing lens is formed in a state where focal distance is 25mm to 35mm, distortion is 0.9% or less, and magnification chromatic aberration is 65mu or less.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film unit with a lens, which has a simple photographing mechanism and has a built-in film in advance. More specifically, the present invention relates to a film unit with a lens for obtaining a print photograph with an aspect ratio of about 1.78. It relates to the film unit.

[0002]

[Prior Art] Can be purchased at a price close to that of ordinary films,
A lens-fitted film unit that does not require a troublesome film loading operation, for example, “Shashinrun Hi” (trade name), is manufactured and sold, and is generally widely used so that a photograph can be taken immediately after purchase. This lens-fitted film unit is a unit in which an unexposed film is built in advance and a simple photographing mechanism is incorporated so that a 35 mm full size (24 mm x 36 mm; aspect ratio 1.5) screen can be photographed. . Also, recently
A film unit with a lens for panorama prints that is shot in an exposure range of 13 mm x 36 mm (aspect ratio of about 2.8), for example, "Sharp Run is Panoramic Hi."
(Brand name) is also on sale.

The print photograph obtained with this "Sharan Lunar Panoramic Hi" is about 89 mm x 254 mm and is powerful, but compared to the standard size of service print of 89 mm x 129 mm, the print size is Since it is large, it has a drawback that it is difficult to put it on the album and it is inconvenient to organize. Therefore, a print photograph creating service called wide vision print (WV print) is performed. The print size of this WV print is 89 mm × 158 mm, and the aspect ratio is 1.78, which is similar to the screen size of a high-definition television. Therefore, there is an advantage that the print size of the print can be attached to the album together with the standard size print photo, though the print size is powerful.

[0004]

However, the above-mentioned W
As mentioned above, the V-print is a print photograph of a slightly elongated deformation size than the standard size. Therefore, in order to receive this service, after developing the photographed film, look at the negative that has finished A WV print will be specially ordered as a reprint print by selecting a frame that does not cause head cuts or cuts when printed. Such work is extremely troublesome and
There is a problem that it takes more time and costs more than general simultaneous printing.

Further, the optimum focal length of the taking lens differs depending on the print size, and is 35 mm for each of the "Sharing Run Hi" and "Sharing Run Panoramic Hi".
It uses a taking lens with a different focal length of 25 mm. Therefore, it is necessary to set the focal length of the taking lens suitable for obtaining a powerful screen of WV printing.

The present invention has been made in consideration of the above circumstances. A WV print having an aspect ratio of about 1.78 can be obtained easily, reliably, and at low cost.
An object of the present invention is to provide a lens-fitted film unit adapted to take a powerful photograph suitable for WV printing.

[0007]

In order to achieve the above object, the lens-fitted film unit of the present invention forms an aperture at a screen ratio of about 1.78: 1 which is wider than the full size, and at the same time, as a photographing lens. Focal length is 25
mm and 35 mm or less, and chromatic aberration of magnification is 65
This is a single-lens lens with μ or less and distortion of 0.9% or less.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a unit main body 10 of a lens-fitted photo film unit has a front cover 12 and a rear cover 13 attached to a main body 11 incorporating a simple photographing device such as a photographing lens and a shutter mechanism. Is. Body 1
1 is a cartridge chamber 16 for accommodating the cartridge body 15 of the photographic film cartridge 14, and the cartridge body 1
A film roll chamber 18 for accommodating the unexposed film 17 pulled out from No. 5 in a roll shape is formed.

A cartridge chamber 16 and a film roll chamber 18
A dark box portion 19 is provided between and, and an aperture 20 for defining a photographing screen is formed at a substantially central portion thereof, and film rails 19a, 19b for defining an image forming surface of the film 17 are sandwiched so as to be convex. It is curved and formed. As shown in FIG. 2, this curvature corresponds to the imaging surface 23 because the taking lens 22 is a single lens made of plastic and the imaging surface 23 thereof is curved.

The rear cover 13 is formed with a pressure plate portion 13a curved in a concave shape corresponding to the convex film rails 19a and 19b. Further, the rear cover 13 has a lid 13
b is rotatably formed, and by opening it, the photographed film cartridge 14 which has been taken can be taken out from the cartridge chamber 16.
Although not shown, the lens-fitted photo film unit is used with the unit body 10 covered with a packaging body such as a paper box.

In FIG. 3 showing the relationship between the film 17 and the aperture 20, the aperture 20 is for WV printing which is narrower than the 35 mm full size (24 mm × 36 mm; aspect ratio 1.5) screen 24 shown by the dotted line. It is “Da × Db”. Here, for example, Da = 2
0.5 mm, Db = 36 mm, aperture 20
Has an aspect ratio of about 1.78.

Diagonal line of aperture 20 Dc = 41.4
In order to determine the optimum angle of view of the taking lens 22 with respect to 3 mm, WV prints were made from negatives taken by taking lenses of various angles of view, and the results of evaluation in terms of force are shown in FIG. As is apparent from FIG. 4, it is understood that the field angle of 60 to 80 degrees indicated by the range α is effective. The focal length corresponding to this angle of view is 25 mm to 35 m
Therefore, it is desirable that the taking lens of the lens-fitted film unit of the present invention has a length of 25 mm or more and 35 mm or less. In addition, in FIG. 4, the vertical axis representing the evaluation indicates that the larger the number is, the more powerful the printed photograph is.

In FIG. 5, when a straight line portion of an object is photographed by the taking lens 22, the distortion aberration (Distortion) which indicates the degree of image bending on the film 17 is 0.9% (TV
Measurement by method) Further, in FIG. 6, the chromatic aberration of magnification having different image magnifications for each color light causes color bleeding and color misregistration. The vertical direction) is preferably 65 μm or less.

A user who purchases the lens-fitted film unit configured as described above operates the winding knob 25 until it stops, and the first frame for shooting is the aperture 2.
It is set to 0 and the shutter charge is performed. When the shutter button is pressed toward the desired subject with the taking lens, the shutter mechanism incorporated in the main body 11 is driven, and the subject image is exposed on the surface of the film 17 set in the aperture 20.

When all the frames of the film 17 are photographed by alternately repeating the operation of the winding knob 25 and the pressing of the shutter button, the user continuously operates the winding knob 25 to expose the inside of the cartridge body 15. Store all the films 17. After that, the lens-fitted photo film unit is submitted to the photofinishing shop as it is and sent to the photo lab. Here, a part of the paper box is peeled off, the lid 13a of the cartridge chamber 16 is opened, and the exposed photographic film cartridge 14 is taken out from the unit main body 10. The photographic film cartridge 14 is set in the print processor for WV printing, and is automatically developed and printed. Then, the developed negative and the powerful WV print are simultaneously given to the user.

In the embodiments described above, a single spherical lens made of plastic is used as the taking lens because it is advantageous in terms of cost. However, both surfaces of the lens are made aspherical in order to remove spherical aberration. You may shape. The taking lens may be optical glass instead of plastic.

[0017]

As described above, according to the lens-fitted film unit of the present invention, the aperture is formed to have a screen ratio of about 1.78: 1 which is horizontally longer than the full size, and
WV printing with an aspect ratio of about 1.78 is easy by using a single lens with a focal length in the range of 25 mm to 35 mm and a lateral chromatic aberration of 65 μ or less and distortion of 0.9% or less. -It is possible to obtain a reliable and low-cost and powerful WV print.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a unit body of a lens-fitted film unit.

FIG. 2 is an explanatory diagram showing an image plane of a photographing lens.

FIG. 3 is an explanatory diagram showing a size relationship between a film and an aperture.

FIG. 4 is a graph in which WV prints taken by taking lenses having different angles of view are evaluated in terms of force.

FIG. 5 is a graph showing distortion of a photographing lens.

FIG. 6 is a graph showing chromatic aberration of magnification of a taking lens.

[Explanation of symbols]

 10 Unit Main Body 11 Main Body 13a Pressure Plate 17 Film 17a Negative 19a, 19b Film Rail 20 Aperture 22 Photographic Lens 23 Imaging Surface

Claims (1)

[Claims] 1. A lens-fitted film unit comprising a unit body incorporating a photographing mechanism such as a photographing lens and a shutter, an unexposed film preloaded in the unit main body, and an aperture for defining a photographing screen of the film. The aperture is about 1.7 longer than the full size.
In addition to forming a screen ratio of 8: 1, a single-lens lens having a focal length of 25 mm or more and 35 mm or less, a lateral chromatic aberration of 65 μ or less and a distortion aberration of 0.9% or less is used as the photographing lens. The featured film unit with lens.