GB2070792A

GB2070792A - Copy camera

Info

Publication number: GB2070792A
Application number: GB8106137A
Authority: GB
Original assignee: Dainippon Screen Manufacturing Co Ltd
Current assignee: Dainippon Screen Manufacturing Co Ltd
Priority date: 1980-02-29
Filing date: 1981-02-26
Publication date: 1981-09-09
Also published as: FR2477293A1; DE3106646A1; JPS56122023A; FR2477293B1; GB2070792B

Abstract

An image of an original 21 on a holder 19 is projected through an objective lens 8 on to photosensitive material 14 held against a suction box 12. Holder 19 is movable along the optical axis. Lens 8 is also movable along the optical axis but is also movable transverse to the optical axis by means of a rotary nut 6 on a screw shaft 5 and a nut 9 fixed to lens holder 7. The photosensitive material is fed by means of driven roller 16, cut by cutter 18, and deposited after exposure in receiver 22. <IMAGE>

Description

SPECIFICATION A method and machine for adjusting a picture image on a photosensitive material for use in a process camera This invention relates to a method and machine for adjusting a picture image on a photosensitive material for use in a process camera.

In a conventional process camera wherein a photosensitive rolled sheet film is used, a film cutter is mounted to a fixed position, and hence an original picture to be photographed should be adjusted to the most appropriate position depending on the size of the original picture and a reproduction scale so that the entire image of the original picture may be photographed onto the film and the waste of the film may be eliminated. Such a process camera includes a complicated mechanism, for example, as disclosed in Japanese Patent Publication No. 52-37373 wherein the film is supported by a combination of a perforated endless belt and a vacuum suction means. Accordingly, it is difficult to support the film in an accurate position.

Therefore, it is an object of the present invention to provide a method of adjusting a picture image on a photosensitive material for use in a process camera which is free from the aforementioned disadvantages, which is simple, accurate and economical, and which can be utilized generally in various cameras.

It is also an object of the present invention to provide a machine for adjusting a picture image on a photosensitive material for use in a process camera which is free from the aforementioned disadvantages, which is simple, accurate and economical, and which can be utilized generally in various cameras.

According to the present invention there is provided a method for adjusting a picture image on a photosensitive material for use in a process camera wherein an original picture is focused on a photosensitive material which is positioned at a certain distance away from the original picture, through a focusing lens means according to the desired reproduction scale, and the position of the focusing lens means is adjusted in accordance with the reproduction scale and the size of the original picture by moving it in a direction perpendicular to the optical axis so that the entire picture image may be projected exactly onto the photosensitive material.

According to the present invention there is also provided a machine for adjusting a picture image on a photosensitive material for use in a process camera wherein an original picture is focused on a photosensitive material which is positioned at a certain distance away from the original picture, through a focusing lens means according to the desired reproduction scale, said machine including an adjusting means for moving the said focusing lens means in a direction perpendicular to the optical axis in accordance with the reproduction scale and the size of the original picture so that the entire picture image may be projected exactly onto the photosensitive material.

The invention is illustrated by way of example in the accompanying drawings, in which: Figure 1 is a longitudinal sectional view of a process camera to which a method according to the present invention is applied; and Figure 2 is a schematic view of a projection of an original picture onto a photosensitive material for the explanation of the present invention.

Referring now to the drawings there is shown in Figure 1 a process camera to which a method according to the present invention is applied.

A photosensitive film holder 1 is vertically positioned, and a bracket 2 projects frontwards in the horizontal plane from the top portion of the film holder 1. A focus adjusting plate 3 is movably mounted to the bracket 2 for movement frontwards and rearwards along the bracket 2. A bearing means 4 having a pair of bearings 4a and 4b aligned vertically is secured onto the lower surface of the adjusting plate 3. A screw shaft 5 is rotatably supported by the bearings 4a and 4b, and can be rotated by an adjusting nut 6 which is arranged between the bearings 4a and 4b and engages with the screw shaft 5.

A lens holder 7 which holds a focusing lens 8 is connected to the lower part of the screw shaft 5 through a nut 9 attached to the lens holder 7. Accordingly, the lens 8 can be moved frontwards and rearwards together with the adjusting plate 3 and up and down by turning the adjusting nut 6. The front window frame 10 of the film holder 1 is connected to the lens holder 7 by beilows 11 so that the inside of the film holder 1 may be shielded against the entry of light.

In the film holder 1, a suction box 12 having a perforated suction surface in its front is vertically arranged just behind the window frame 10 and it is connected to a vacuum suction means (not shown) through a suction pipe 13 connected to the suction box 12 on its rear surface.

A spool 15 on which a photosensitive rolled sheet film 14 is positioned, is arranged in the rear top of the film holder 1. The film 14 is fed from the spool 15 to the front suction surface of the suction box 12 between a feed roller 16 connected to a drive means (not shown) and a pressure roller 17 contacted thereto, and via a cutter 18 arranged just above the suction box 12, and is held onto the front surface of the suction box 12 by actuating the suction means.

A picture holder 19 is vertically arranged in front of the lens holder 7 at a certain distance away from the film holder 1. The picture holder 19 can usually be movable frontwards and rearwards so as to adjust the distance from the film holder 1. A positioning pin 10 is secured to the surface of the picture holder 19 at the same height as the top end of the suction box 12, and original picture 21 is mounted to the surface of the picture holder 19 in contact with the positioning pin 20 at its top end.

After the original picture 21 is photographed by the camera of Figure 1, the exposed part of the rolled film 14, which is held on the front surface of the suction box 12, is cut off by the cutter 18. Then, the suction box 12 is disconnected from the suction means, and the exposed film 14, which has been cut off drops down into a receiver 22 positioned in the lower part of the film holder 1. In this case, photographs may be made on the film 14 consecutively several times without cutting the film, and then the relatively long film 14 which has been exposed may be cut off, or the film 14 may be cut off by the cutter 18 before photographing.

In this embodiment, in order to photograph the entire picture image exactly onto the film 14 and to eliminate waste of the film 14, the upper and the lower ends of the picture image should be projected to register with the lower and the upper end parts of a cut film 14' held by the suction box 12. The position and the size of the picture image projected on the film 14 depend on the position of the original picture 21 and the reproduction scale.

According to the present invention the vertical length of the film 14 can readily be varied by feeding the film 14 by using the feed roller 16, and, since the cutter 18 and the suction box 12 are fixed, the position of the picture image in the vertical direction may be changed by moving the height of the optical axis of the focusing lens 8 by turning the screw shaft 5 by rotating the adjusting nut 6, as explained in detail below.

In Figure 2 there is shown a schematic view of a projection of the original picture 21 onto the film 14' through the focusing lens 8, wherein the tops of the original picture 21 and the film 14' are not the same height, as described above. Now, assuming that the focal distance of the focusing lens 8, the distances between the focusing lens 8 and the original picture 21 and between the focusing lens 8 and the film 14', the vertical lengths of the original picture 21 and the film 14', the distance between the top of the original picture and the focusing lens 8, and the reproduction scale are f, a, b, L, e, h and m, respectively, the following equations are obtained: 111 bCh -+ 11 and m = a = L abf Then, the following equations result from these two equations.

b=f(1 + m) i = mL

From these equations it is readily understood that, when f, Land m are given, b, a+b, C and h can be calculated. Further, the focusing lens 8 can be adjusted in the proper height by moving up or down the focusing lens 8 according to the last equation described above, so that the entire picture image of the picture 21 may be photographed exactly onto the film 14' without causing the waste of the film 14'.

In this embodiment, the lens holder 7, the picture holder 19, the feed roller 16 and the cutter 18 may be driven manually or automatically by an appropriate drive means.

Although the present invention has been described with reference to a preferred embodiment thereof, however, various changes and modifications can be made by those skilled in the art without departing from the scope of the present invention.

Claims

1. A method for adjusting a picture image on a photosensitive material for use in a process camera wherein an original picture is focused on a photosensitive material which is positioned at a certain distance away from the original picture, through a focusing lens means according to the desired reproduction scale, wherein the position of the focusing lens means is adjusted according to the reproduction scale and the size of the original picture my moving it in a direction perpendicular to the light axis so that the entire picture image may be projected exactly onto the photosensitive material.

2. A method as claimed in claim 1, wherein the one ends of the original picture and the photosensitive material are positioned at the same height.

3. A method as claimed in claim 2, wherein the distance h between the light axis of the focusing lens and the one end of the original picture is determined in the following equation wherein m means a reproduction scale and L means a vertical length of the original picture:

4. A method as claimed in any of claims 1 - 3, wherein the original picture is mounted in contact with a positioning means.

5. A method as claimed in claim 1, substantially as described herein.

6. A machine for adjusting a picture image on a photosensitive material for use in a process camera wherein an original picture is focused on a photosensitive material which is positioned at a certain distance away from the original picture, through a focusing lens means according to the desired reproduction scale, said machine including an adjusting means which moves the focusing lens means in a direction perpendicular to the light axis depending on the reproduction scale and the size of the original picture so that the entire picture image may be projected exactly onto the photosensitive material.

7. A machine as claimed in claim 6, wherein the one ends of the original picture and the photosensitive material are positioned at the same height.

8. A machine as claimed in claim 7, wherein the distance h between the optical axis of the focusing lens and the one end of the original picture is determined in the following equation wherein m means a reproduction scale and L means a vertical length of the original picture:

9. A machine as claimed in any of the claims 6 - 8, wherein the original picture is mounted in contact with a positioning means.

10. A machine as claimed in any of claims 6 - 8, wherein the photosensitive material comprises a folled sheet film.

11. A machine as claimed in any of claims 6 - 8, wherein the photosensitive material is held by a suction box.

12. A machine as claimed in claim 6 substantially as described herein with reference to the accompanying drawings.