GB2040057A - Copying - Google Patents

Abstract

Optical fibres are arranged singularly, in a bundle or with ends side-by- side for transmitting light, eg from an original to a photoconductive drum (Figure 1), a photoconductive sheet (with crossing over of the fibres, Figures 2 and 8) or corresponding photodetectors for facsimile reproduction (Figure 14). Random crossing of the fibres produces a coded image which may be decoded using a complementary crossing arrangement.

Description

SPECIFICATION The use of fibre optics or light guides in or relating to light sensitive copying equipment At present the "Optical Scanning System" on Light Sensitive Copying Equipment requires a series of Mirrors and Lenses to project a strip image onto a Light/Photo Sensitive Drum or Paper. The present invention would use "Fibre Optics or Light Guides" instead of these mirrors and lenses, thus increasing the range of present day Light Sensitive Copying Equipment to cover (a) Normal copying of documents etc.. (b) Encoding (scrambling and Decoding (unscrambling) of Secret of Confidential documents etc.. (c) Transmission and/or Storage of copies of documents etc. in computers or similar equipment.

(d) Remote scanning of items too large to place on photo copiers scanning beds. (e) as an alternative light source.

Definition of "Fibre Optics of Light Guides" Fibre Optics provides a flexible glass or plastic medium for the transmission of light or images.

Each fibre consists of a core and cladding, light is transmitted along the core by total internal reflection from the cladding interface.

Thousands of fibres arranged together to form a "Bundle" which may be sheathed in PVC or other material to yield a Flexible Fibre Optic cable or strip.

There are two types of Bundle "Non-Coherent" for the simple light transmission of images. These fibres in the bundles can be arranged to produce (a) Normal Image. Figure 3. (b) Reversed Image Figure 4 (c) Inverted Image Figure 5. (d) Inverted Reversed Image. Figure 6.

The present invention requires that the fibres are arranged into "Coherent" bundles, the length of these bundles is determined by the distance from the scanning area to the exposure area. The ends of these bundles, the length of these bundles is determined by the distance from the scanning area to the exposure area. The ends of these bundles (which are preferably arranged into square or rectangular end sections) are fixed rigidly side-by-side to form a continuous strip of fibre ends which are ground and polished to give a good optical finish. The body of this flexible optic strip is covered in PVC or other material.

As there are two ends of the strip and in order to avoid confusion one end shall be referred to as the Scanning End the other the Exposure End. The thickness of this "Copying Strip" is determined by the "Light/Time Ratio" needed to produce a clear copy. The width of the "Copying Strip" is determined by the width of the scanning carriage on the light sensitive copying equipment (a) Normal Copying of documents etc.

For copying equipment that utilises a revolving "Light/Photo sensitive drum" Figure 1 a "Normal Image" is usually required and the method of assembly for the "Copying Strip" is as following:- The fibres in the bundles are arranged to produce "Normal Images", these bundles are assembled parallel to each other to form a flat flexible strip, Figure 7, which is then covered in PVC or other material, the ends of this strip are then ground and polished to give a good optical finish. The "Scanning End" of the strip is positioned across the scanning carriage together with the light source and the "Exposure End" is positioned to project a strip image across the revolving light/photo sensitive drum.For copying equipment that utilises "Light/ Photo sensitive paper", Figure 2 a "Reversed Image" is usually required and the method of assembly for the "Copying Strip" is as follows: The fibres in the bundles are arranged to produce "Reverse Images", then the first bundle on the extreme left of the "Scanning End" cross the centre line of the strip and are positioned on the extreme right of the "Exposure End" Figure 8. The second bundle from the left crosses over to become the second bundle from the right. The third from the left becomes the third from the right etc. etc. until finally, the bundle on the extreme right of the "Scanning End" becomes the bundle on the extreme left of the "Exposure End". This X shaped "Copying Strip" is covered in PVC or other material and the ends are ground and polished.The "Scanning End" is then positioned across the scanning carriage together with the light source and the "Exposure End" is then positioned to sweep over the light/photo sensitive paper.

(b) Encoding and Decoding of Secret or Confidential documents In order to Encode or scramble copies of documents, "Normal or Reversed Image" bundles are preferred, but "Inverted or Inverted Reversed Image" bundles could be used for more difficult coding. The method of assembly for the "Coding Strip" is as follows: The first on the extreme left of the "Scanning End" is positioned anywhere along the "Exposed End".

The second bundle from the left is then positioned along the "Exposure End" to start forming a "Set Random Pattern". The rest of the bundles are then positioned and fixed to complete the "Set Random Pattern" Figure 9, this "Set Random Pattern" is the "Code Sequence". This "Coding Strip" is then covered in PVC or other material and the ends are ground and polished.

The "Scanning End" is then positioned across the scanning carriage together with the light source and the "Exposure End" is positioned to project the scattered image onto the light/photo sensitive drum or paper.

It is preferable that the bundles used in the "Coding Strip" are rectangular in end section as thin as possible so that when a copy is made through this "Coding Strip", each letter, mark or number on the original document etc. is divided into a series of vertical parts which are scattered across the copy, this will produce a completely illegible copy consisting of vertical lines and dots which would be difficult to Decode unless it is re-copied with a similar piece of equipment containing a "Decoding Strip" which requires to be assembled in the reverse order to that of the "Encoding Strip" Figure 10.

In order to obtain a clear Decoded or Unscrambled copy, the Encoded document has to be placed over the "Decoding Strip" is exactly the same position as the original document. This could be achieved electronically or with a clear plastic mask or frame with reference lines marked on it, or simply by moving the Encoded copy over the illuminated scanning bed until the lines and dots form a legible image across the exposure area (This could be viewed by another fibre optic strip similar to Figure 7.) If it is required, one photo-copier may be equipped with the three fibre optic strips "Normai, Encoding and Decoding", fixed one in front of the other and a simple shuttering device could be operated to cover the "Scanning End" of the optical strips not in use.

(c) Transmission of copies andlor Storage of copies in Computers, etc.

For transmission of copies of documents to other equipment, i.e. Copiers, Computers, etc. it is preferably to use 'Single strand plastic coated silica low loss optical fibre for data transmission" and the method of assembly for the "Transmitting Strip" is as follows: The single fibre strands are fixed rigidly side-byside at the "Scanning End" to form a continuous line of fibre ends, the "Exposure End" of these fibre strands are fitted into detector units (one detector per fibre), which can be mounted on the ends or side of the equipment. The body of this "Transmitting Strip" can be kept in a flat strip or bunched together, then covered in PVC or other material and the ends are group and polished. The "Scanning End" of this flexible "Transmitting Strip" is positioned across the scanning carriage together with the light source.

The principle of this fibre optic system is then as the "Scanning End" of the "Transmitting Strip" passes vertically over the illuminated original, for example, the letter T (which could be covered by five fibre ends Nos. 1,2,3,4,5) Figure 11. The light sequence reflected by this letter would be as follows: (a) They would all start off light, then (b) fibres 2,3,4 would become dark (for the base of the T) then (c) fibres 2 and 4 would become light again leaving 3 still dark the vertical centre line of the T) then (d) fibres 1 and 5 would become dark the same as 3 (the two lower tips on the extreme ends of the crossing line of the Tand the centre line), then (e) all five fibres 1,2,3,4,5 would become dark (the crossing line), then (f) they would all become light again as the letter is passed.These pulses of light and dark are transmitted down the fibre strands and projected onto five light/photo sensitive detectors which covert these pulses of light into pulses of electricity.

These pulses of electricity would travel to other "light sensitive copying equipment" or stored or used in Computers either direct or indirect via telephone or radio, it can aiso be fed straight into the "Receiving Strip" of the same machine to produce a normal copy.

In order to obtain a copy, these pulses of electricity would be fed into miniature light sources (LEDs or filaments) which are positioned at the end of the fibres in the "Receiving Strip" (one light source per fibre), as the light sources react to the pulses of electricity, pulses of light are then transmitted down the fibres and projected onto the light/photo sensitive drum or paper.

The "Receiving Strip" is assembled in the same method as the "Transmitting Strip", but will have an "Exposure end" and a "Receiving End" which is fed into the lighting unit. This "Exposure End" is fixed in position to project the light/dark sequence onto the light/photo sensitive drum or paper, as the surface of the drum or paper passes the "Exposure End" a copy of the original item will be produced.

This Transmission system could also be used for Normal Copying, Encoding and Decoding of documents simply by switching electronically the pulses of electricity received from the transmitting unit before they are fed into the receiving unit, Figure 14.

(d) Remote scanning By using "Copying Strips" of extended length, it would be possible to copy items which could not be placed onto normal copying equipment, provided that the scanning carriage speed of travel over the item is equal to the speed of the light/photo sensitive drum or paper past the "Exposure End" and the scanning illumination level is correct.

(e) Light source An alternative light source can be provided with this present invention by preferably using Non Coherent bundles of fibres arranged into a flexible "Projection Strip" which will produce a strip of light across the scanning carriage from a stationary light source. The method of assembly for the "Projection Strip" which will produce a strip of light across the scanning carriage from a stationary light source.The method of assembly for the "Projection Strip" is as follows: One end of the bundle of fibres is preferably arranged into rectangular or square end section, these ends are rigidly fixed side-by side to form a continuous strip of fibre ends, the other ends of the bundles are preferably gathered together and fixed rigidly to form a circle, the area of which is equal to the sum of strands in all the bundles in the "Projection Strip", the body of this "Projection Strip" is then covered in PVC or other material and the ends are ground and polished. The continuous strip of fibre ends shall be referred to as the "Projection End" and the circle of fibre ends shall be referred to as the "Lighting End".

The "Projection End" of this "Projection Strip" is positioned across the scanning carriage at such an angle that will allow the maximum amount of light reflected off the original item to be copies, being received by the "Scanning Ends" of the copying strips. The "Lighting End" of this "Projection Ends" of the copying strips. The "Lighting End" of this "Projection Strip" is positioned to receive the maximum amount of light from a stationary light source Figure 12 or one similar to that of a film projector, where the light from a Quartz-Halogen Lamp is projected onto the "Lighting End" of the "Projection Strip" via lenses and reflector.This Light Source would be most suitable for the "Remote Scanning Strip" where the Projection Fibres and Copying Fibres can be assembled together to form one flexible cable and the "Scanning End" could form one unit together with the "Projection End" Figure 13.

Description of Drawings By way of example only fourteen specific embodiments of this invention will now be described referring to the accompanying drawings in which: Figure 1 shows the "Fibre Optic Copying Strip" in position on the revolving Light/Photo Sensitive Drum type photo copier.

Figure 2 shows the "Fibre Optic Copying Strip" in position on the light/Photo Sensitive Papertype copier Figure 3 shows the fibres arranged in the bundles to produce a "normal Image".

Figure 4shows the fibres arranged in the bundle to produce a "Reversed Image" Figure 5 shows the fibres arranged in the bundle to produce an "Inverted Image" Figure 6 shows the fibres arranged in the bundle to produce an "Inverted Reversed Image" Figure 7 shows the "Normal Image" bundles arranged to produce a "Normal Image Copying Strip" Figure 8 shows the "Reversed Image bundles arranged to produce a "Reversed Image Copying Strip".

Figure 9 shows the Fibre Bundles arranged to produce a sample encoding pattern Figure 10 shows the Fibre Bundles arraged to produce the Decoding pattern for Figure 9 Figure 11 shows the Light/Dark sequence as the fibre strands pass vertically over the letter'T in the Transmission and Storage of copies section of the above specification.

Figure 12 shows an ellipsoidal reflector in position to give even illumination over the "Lighting End" or the "Projection Strip".

Figure 13 shows a remote scanning head com plebe with "Projection and Lighting Strips".

Figure 14 shows the "Transmitting Receiving and Lighting Strips" in position on a Transmission and Storage Copier (strip supports omitted.) Referring to Figure 1 of the drawings, there is shown (1) the scanning carriage, (2) the scanning rails (3) The Reflector (4) The Light source (5) The "Normal Image" copying strip (6) The "Scanning End" (7) The "Exposure End" (8) The light/photo sensitive drum.

Referring to Figure 2 of the drawings, there is shown (1) The Scanning carriage (2) The scanning rails (3) The reflector (4) The light source (5) The "Reversed Image copying strip" (6) The "Scanning End" (7) The "Exposure End" (8) The light/photo sensitive paper (9) The exposure bed.

Referring to Figures 3, 4, 5, 6, of the drawings, there is shown a simplified version of how the fibres strands are arranged in the "Coherent Bundles".

(a.b.c.d.e.f.g. denote the strand ends for easy reference).

Referring to Figures 7,8,9,10 of the drawings, there is shown (1 ) the "Scanning End". (2) The body of the copying strip (3) The "Exposure End". The letters a-v represent the sequence of how the image will appear on the exposure surface.

Referring to Figure 11 of the drawings, this shows the light/dark sequence of the strands 1,2,3,4,5 as they pass vertically over the letter T (a) is the first sequence, (b) is the second, (c) the third, (d) the fourth (e) the fifth, (f) the sixth.

Referring to Figure 12 of the drawings, there is shown (1) the "Lighting End" of the fibre optic "Projection Strip" (2) The ellipsoidal reflector (3) The lamp or light source (4) Light rays.

Referring to Figure 13 of the drawings, there is shown (1) The Scanning Head (2) The "Scanning End" of the copying strip (3) The "Projection End" of the Lighting strip (4) the "Lighting End" of the "Lighting Strip" (5) The "Exposure End" of the copying strip.

Referring to Figure 14 of the drawings, there is shown (1) The "Transmitting Strip" (2) The "Scanning End" (3) The "Detector Unit" into which the "Exposure End" of the copying strip is fixed. This "Detector U nit" contains one detector for each fibre strand. (4) The "Projection Strip" (5) the "Projection End" (6) The "Lighting End" which continues to the light source (7) The "Receiving Strip" (8) The "Lighting Unit" into which the "Receiving End" of the receiving strip is fixed. This lighting unit contains one light source for each fibre strand. (9) The "Exposure End" (10) The exposure bed (11) The scanning head (12) The outer casing.

Claims (1)

1. The main claim for the present invention is the use of flexible strands of glass or plastic medium known as "Fibre Optics or Light Guides" for the transmission of light or image from the scanning area to the exposure area for use in or relating to "Light Sensitive Copying Equipment" by arrangement of these fibre strands either singularly, in bundles, or side by side to form a strip or block to project or transmit (a) a "Coherent" image, (b) a "Non-Coherent image, or (c) any combination of (a) and (b) above, for use in producing (d) normal copies, (e) encoded (Scrambled) copies, (f) decoded (unscrambled) copies, (g) transmission and/or storage, (h) remote scanning of documets etc., (i) as an alternative light source for copying equipment.