FR2477293A1 - METHOD AND MACHINE FOR ADJUSTING AN IMAGE ON A PHOTOSENSITIVE MATERIAL INTENDED TO BE USED IN A REPRODUCTION CHAMBER - Google Patents

Abstract

AN ORIGINAL IMAGE IS FOCUSED ON PHOTOSENSITIVE MATERIAL 14 AVAILABLE AT A CERTAIN DISTANCE FROM THE ORIGINAL IMAGE 21 AND BY MEANS OF A FOCUSING LENS 8, ACCORDING TO THE REPRODUCTION SCALE DESIRED. THE POSITION OF THE FOCUSING LENS 8 IS ADJUSTED BY ADJUSTING MEANS 3: 4A, B; 5; 6 DEPENDING ON THE SCALE OF REPRODUCTION AND THE DIMENSIONS OF THE ORIGINAL IMAGE BY MOVING IN A DIRECTION PERPENDICULAR TO THE LUMINOUS AXIS SO THAT THE ENTIRE IMAGE CAN BE PROJECTED WITH PRECISION ON THE PHOTOSENSITIVE MATERIAL WITHOUT WASTE PHOTOSENSITIVE MATERIAL.

Description

The present invention relates to a method and a machine for adjusting a

  image on photosensitive material,

intended to be used in a reproduction chamber

  tion. In conventional reproduction chambers where a photosensitive film wound on a reel is used, a knife is mounted in a fixed location and the result is that an original image which one wishes to photograph must be placed in the position suitable for it. better based on

  dimensions of the original image and the reproduction scale

  duction so that the entire original image can be photographed on film and to avoid waste

of the film. These reproduction chambers include a mechanism

  complicated mechanism such as that described in Japanese patent 52.37373 o the film is supported by a combination of an endless perforated belt and suction means making the vacuum. It is therefore difficult to keep the film in a

precise position.

An object of the present invention is therefore to propose

a method of adjusting the image on a photosensitive material

  sible intended to be implemented in a

reproduction, which does not have the disadvantages mentioned-

  born and which is otherwise simple, precise and economical, and capable of being used generally in the

  most breeding rooms.

  Another object of the invention is to provide a machine for adjusting an image on a photosensitive material intended for use in a reproduction chamber, which does not have the drawbacks mentioned, which is simple, precise and economical, and who can be

used in most breeding rooms.

According to the invention, there is proposed a method for adjusting an image on a photosensitive material intended to be used in a reproduction chamber, o an original image is developed on a photosensitive material arranged at a certain distance from the original image and by means of a focusing lens, according to the desired reproduction scale, characterized in that the position of the focusing lens is adjusted according to this

  reproduction scale and dimensions of the original image

  gine by moving it in a direction perpendicular to the light axis so that the whole image can

be precisely projected onto the photosensitive material.

  According to the present invention, it is also proposed

a machine for adjusting an image on a photo material

sensitive intended to be used in a repro chamber

  duction, where an original image is focused on a photosensitive material placed at a certain distance from this image by means of a focusing lens and according to the desired reproduction scale, characterized in that it includes adjustment means which move

  the focusing lens in a direction perpendicular to

  beam to the light axis according to the scale of repro-

duction and dimensions of the original image so

  that the entire image can be projected with precision

sion on the photosensitive material.

  To better understand the invention, a preferred embodiment will now be described with reference to the accompanying drawings in which: FIG. 1 is a view in longitudinal section of a reproduction chamber to which the method according to the invention is applied, and FIG. 2 is a schematic view of a projection of an original image on a photosensitive material, allowing

to explain the invention.

  Referring now to the drawings, FIG. 1 represents a reproduction chamber to which is

applied the method of the invention.

A support for a photosensitive film 1 is arranged vertically

  and a console 2 protrudes forward in a

  horizontal plane at the top of the film holder 1.

  A focus adjustment plate 3 is movably mounted on the console 2 and can move forward and backward on this console. Support means comprising a pair of bearings 4a and 4b in vertical alignment are fixed to the lower surface of the adjustment plate 3. A threaded shaft 5 is rotatably supported by the bearings 4a and 4b, and it can be turned at by means of an adjusting nut 6 disposed between the bearings 4a and 4b and cooperating with the threaded shaft 50 A lens support 7 which contains a focusing lens 8 is connected to the lower part of the threaded shaft 5 by by means of a nut 9 fixed to the support 7. As a result, the lens 8 can be moved forwards and backwards at the same time as the adjustment plate 3 and up and down in turning the adjusting nut 6. The front window 10 of the film holder 1 is connected to the lens holder 6 by a bellows II so that the interior of the film holder 1 can be

protected from light.

  A suction box 12 provided with a perforated suction surface at its front part is arranged vertically in the film support 1 just behind the window 10 and the vacuum is created there by suction means (not shown ) and via a suction hose

  13 connected to the box 12 on its rear surface.

  A reel 15 on which a photo film is wound

sensitive 14 is arranged at the upper rear end of the film support 1. The film 14 comes from the reel 15 on the front suction surface of the suction box 12 passing between a supply roller 16 connected to a roller drive (not shown) and a push roller 17 which is in contact with it, and against a knife 18 disposed just above the suction box 12, and the film is kept applied against the surface before

the suction box 12 when the vacuum means are actuated

  ration. An image support 19 is mounted vertically in front of the lens support 7 at a distance from the film support 1. Usually, the image support 19 can be moved forward and backward to adjust the distance which separates it from the film support 1 o A positioning tip 10 is fixed on the surface of the image support 19 at the same height as the upper part of the suction box 12, and an original image 21 is mounted on the surface of the image support 19 in contact with the tip

  positioning 20 at its upper part.

  When the original image 21 has been photographed by the camera of FIG. 1, the exposed part of the film 14 which is kept pressed against the front surface of the suction box 12 is cut by the knife 18. The suction is then stopped in the suction box 12 and the exposed film 14 ′ which has been cut falls out in a collector 22 disposed at the lower part of the film support 1. As a variant, several photographs can be taken consecutively on the film 14 before cutting it and a film 14 of a certain length and exposed is then cut, or alternatively the film 14 can be cut by the knife 18 before taking the photograph. In this embodiment, to photograph the entire image exactly on the film 14 and avoid

wasting film 14, the upper and lower ends

  re of the image must be projected on the finished parts

lower and upper nales of the cut film 14 ′ held by the suction box 12. The position and dimensions of the image projected on the film 14 depend on the position of

the original image 21 and the reproduction scale.

  According to the present invention, the vertical length of the film 14 can be easily changed by means of the feed roller 16, and since the knife 18 and the suction box 12 are fixed, the position of the image can be changed in the direction vertical by moving the height of the light axis of the focusing lens 8 by turning the threaded shaft 5 using the adjusting nut 6, as

  this will be explained in more detail below.

Fig. 2 is a schematic view of the projection of an original image 21 on the film 14 'via the focusing lens 8, the upper parts of the original image 21 and the film 14' being at the same height, as described above. Now assuming that the focal length of the focusing lens 8 is represented by "f", the distance between the focusing lens 8 and

  the original image 21 by "a" and the distance between the

  focusing lens 8 and the film 14 'by "b", the vertical length of the original image 21 by "L", that of the film 14' by "t", the distance between the upper part of l original image and the focusing lens 8 by "h" and the reproduction scale by "m", we can write the following equations: 1 + i 1 and = = hab = and m = -7- h From these, we deduce: a = f (1 + m) b = f (l + m) = mL 1 + mh = (-) LA examining these equations, we can easily see that when we know " f "," L "and" m ", we can calculate" b "," a + b "," t "and" h ". In addition, the focusing lens 8 can be adjusted to the correct height by raising or lowering it according to the last equation above, which makes it possible to photograph the entire image 21

  exactly on 14 'film without wasting film.

  In this embodiment, the lens holder 7, the image holder 19, the feed roller 16 and the

  knife 18 can be operated by hand or automatic-

  thanks to appropriate drive means.

  Although the invention has been described with reference to a preferred embodiment, a person skilled in the art can however

  make various variations and modifications without deviating

ter of its scope.

Claims (10)

1. Method for adjusting an image on a photosensitive material intended to be used in a reproduction chamber, where an original image is developed on a photosensitive material placed at a certain distance from the image original and by means of a focusing lens   to the point, according to the desired reproduction scale, character- terized in that the position of the focusing lens (8) is adjusted according to the reproduction scale and the dimensions of the original image by moving it in a direction perpendicular to the light axis so that the entire image can be projected precisely onto the photosensitive material. 2. Method according to claim 1, characterized in that one end of the original image is disposed at the same   height than one end of the photosensitive material.   3. Method according to claim 2, characterized in that the distance "h" between the light axis of the focusing lens and one end of the original image is determined by the equation: h = (' ) L l + mo "m" represents the reproduction scale and "L" la vertical height of the original image. 4. Method according to any one of claims 1 to 3, characterized in that the original image is mounted in   contact with a positioning means.   5. Machine for adjusting an image on a photosensitive material intended to be used in a reproduction chamber, o an original image is developed on a photosensitive material placed at a certain distance from the original image to the by means of a focusing lens and depending on the desired reproduction scale, character-   terized in that it comprises adjustment means (3; 4a, b; 5,6) move the lens / focusing in a direction perpendicular to the light axis as a function of the reproduction scale and of the dimensions the original image so that the entire image can be projected with   precision on the photosensitive material. 6. Machine according to claim 5, characterized in that one end of the original image is arranged at the same   height than one end of the photosensitive material. 7. Machine according to claim 6, characterized in that the distance "lh between the light axis of the focusing lens and one end of the original image is determined by the equation: h =) L 1 + mo "'m" represents the reproduction scale and "L" the   vertical height of the original image.   8. Machine according to any one of claims 5 to   7, characterized in that the original image is mopted in   contact with positioning means (20). 9. Machine according to any one of claims 5 to   7, characterized in that the photosensitive material is consisting of a film (14) wound on a reel (15).   10. Machine according to any one of claims 5 to 7, characterized in that the photosensitive material is held by a suction box (12).