US2247348A - Scanning apparatus - Google Patents

Description

A. J. CAWLEY SCANNING APPARATUS July L 34% Filed July 27. 19 31 AAAAAAAAAAAAAAA US Filed July 27, 1931 2 Sheets-Sheet 2 Patented July 1, 1941 were TES

8 Claims.

This application is a continuation in part of my applications Serial No. 391,541 filed September 10, 1929, for Scanning process, and Serial No. 541,006, filed May 29, 1931, for Multiplex scanning system.

The invention relates to method and means for causing light beams to traverse or explore objects or image areas, and is particularly useful in the field of television'for performing trhe function known as scanning.

An object of the invention is the production of brighter, clearer and more detailed images. This is accomplished in general by scanning several component images in diiierent directions and superposing' those images to form. a composite image of great detail and definition. Each of those images may be composed of light of a certain complementary or elementary color and their combination into a composite image produces an image in natural colors.

Still another object of the invention is the employment of an ordinary Nipkow disk or its equivalent, for the production of those composite images, which are in turn made up of several component images scanned indifferent directions.

An object of the invention is also the use of one half or one portion of the disk for the production of several component images, while the other half of the disk may be used for the scanning, of an object and the production of several image varied currents corresponding to several component images scanned in different directions. periphery of the disk may be provided with photoelectric cells for the transmission of images and the other half may be providedwith glow lamps for the reproduction of a receivedimage, thus producing a two-way television apparatus of great simplicity and usefulness. Thus the field of usefulness of the simple Nipkow disk, is greatly widened.

Instead of superposing the various difierently scanned images, they may be projected in juxtaposition. Both transmitter and receiver would in that event be adjusted for juxtaposed projection. The apparatus is instantly convertible into either type, juxtaposed or superposed scanning.

This also forms a very desirable object of the invention.

Other objects of the invention are as follows: The scanning of the difierent component imagessimultaneously or alternately, either by use of special disks having special spacings of the Thus one half of the circumference or lenses or apertures carried on them, or by commutating means hereinafter described.

The intercalated, line for line scanning of the component images, or the complete scanning of each component image, or of portions of each component image alternately.

A special Nipkow disk having a reduced number of apertures or lenses spaced a greater distance apart than usual.

A special Nipkow disk having its spirals broken up into certain groups of lenses or apertures disposed about the periphery of the disk.

The production of a composite superposed image made up of several component images each of which is scanned in a different direction.

The production of a composite image made up of several component images, each of which is differently colored and scanned in different directions and superposed.

Other advantages and objects of the arrangements will be apparent from a consideration of the following specification and claims when read in connection with the accompanying drawings wherein the various figures thereof represent in a: conventional manner the principles covered by the invention.

Figure 1 represents an ordinary Nipkow disk having a scanning means at two difierent portions ofthe periphery, each producing an image scanned in different directions, and those two images are superposed upon each other by projection to form a composite image.

Figure 2 represents a modification quite similar to that of Figure 1, with the exception that each scanning element is supplied with a specific component of the image varied alternating current.

Figure 3 illustrates a modification similar to that of Figure 1 with the exception that four photoelectric elements are shown at four different portionsof the circumference of the scanning disk, each projecting an image that is scanned in a difierent direction from that of its neighbor. Each of theimages may be produced by light of a specific color, and their combination produces an image in natural colors.

Figure 4 shows a disk having its lenses spaced apart in such manner that but one lens traverses an image areaat a time, and eachimage is traversed by a lens alternately. Both of the photoelectric elements are supplied with the same image current.

Figure 5 shows a single-disk which bears lenses arranged in a spiral, but the spiral is divided into two halves which are placed at different portions of the circumference of the disk. The

image in natural colors.

images are scanned alternately in halves. The same current is simultaneously supplied to the photoelectric elements.

Figure 6 illustrates a disk provided with a commutator which acts to scan the images in an intercalated manner, the photoelectric elements being alternately supplied with current.

Figure 7 illustrates a commutating apparatus which may be applied to Figure 6, whereby an image is scanned completely first in one direction and then another component image is completely scanned in another direction.

Figure 8 is an illustration showing the manner of connecting four different glow lamps to two different circuits.

Figure 9 illustrates a method of connecting four glow lamps to the same circuit, spacing the lamps in a specific manner.

Figure 10 illustrates a combined transmitter and receiver utilizing but one disk.

An ordinary Nipkow disk D provided with lenses 2 spirally arranged is shown in Figure 1. neon lamp I or its equivalent is shown projecting its image varied light through the apertures or lenses 2 of the disk. This light is projected by theoptical system R upon the screen S. The arrow 0. indicates that the image or rather the screen is scanned in the horizontal direction. The figure illustrates the receiving apparatus. But obviously S may be taken as the object which is focussed by R. upon the photoelectric cell I. The 7 expression a television translation element covers an electro-optical element which converts image-modulated electric current into a visible image and also covers a photoelectric element or cell which converts an optical image into an image varied current. The former produces an optical image and the latter converts an optical image into image-modulated electric current.

Continuing the description of Figure 1 as representing a receiving arrangement. Neon lamp 3 passes its light through the apertures of the diskD at a point ninety degrees removed from the point of projection of lamp I. This light is projected by means of the optical system B upon the screen S. It will be noticed, however, that the image is scanned vertically or at right angles to the first image, and this fact is represented by the arrow 0 which indicates the direction of scanning of the second image. The two lamps I and 3 are connected separately to difierent circuits carrying image-varied current. Two separate circuits are used at the transmitting station. Figure 1 may be taken also to represent the transmitting station arrangements, the objects being scanned by two optical systems ninety degrees apart on the circumference of the same disk. Two separate image currents are formed at the transmitting station in the photoelectric cells corresponding to glow lamps 2 and 3, and are received and amplified at the receiving station and supplied to the neon lamps I and 3. The result is a composite image made up of two superposed images, each of which is scanned in difi'erent directions simultaneously. 7

It; is very important to note that the two images forming the composite image may be projected in different complementary colors. For

instance, I may be limited to orange-red while 3 maybe limited to blue-violet. The two superposedimages' would then produce a composite rangement' would exist at the transmitting station. In the figure, therefore, I and 3 are con- A corresponding ar-' nected to separate circuits, and both images are: scanned at the same time.

Figure 2 illustrates an arrangement similar to that of Figure 1 but with the distinction that. both of the neon or other lamps I and 3 are: connected to the same circuit through unilateral. conducting elements 8 and 9. The result is that. each lamp receives but one component of the: alternating current. A composite image is; formed on screen S which is simultaneously scanned by the lamps I and 3 and their corre-- sponding optical systems. Lamp I scans an. image horizontally, while lamp 3 scans its image vertically. The arrows a and 0 illustrate this; clearly.

Figure 3 illustrates an arrangement that is: similar to Figure 1 but with the distinction that. four neon or other lamps I, 3, 4 and 5 are used- Those lamps are shown disposed forty five degrees apart throughout the circumference of the: circular disk D. This disk is represented'as an: ordinary Nipkow disk" D provided with lenses 2.. Those lenses are arranged in a spiral. Lamp Ii projectsits light which may be limited to a definite color, such as red, through the lenses 2. Optical system R projects this light upon the: screen S to form an image scanned in the horizontal direction. Lamp 4 passes its light through the lenses 2 and this light is projected upon the screen S to form a second image superposed upon the first. 1 indicates that the light of the first image is scanned in the horizontal direction, while '0 indicates that the second image is scanned in a. direction at an angle of forty five degrees to the first image. The light of lamp 3 is projected after passing through the lenses 2 by means of the optical system B upon the screen S, thus superposing an image again upon the other two. This image is scanned in the vertical direction as indicated by the arrow 1). The light from lamp 5 after passingthrough the lenses 2 is projected upon the screen superposed upon the previous images by the optical system V, and this image is scanned in a direction forty five degrees from the vertical, as shown by the arrow '0. Thus 7 a composite image is formed by projection consisting of four distinct images each scanned in a direction which is forty five degrees removed from that of its neighbor.

Each of those images may be projected in a definite complementary color either by having the lamps themselves emit light of a definite color or by use of color screens in the well known manner, the resulting composite image being in natural colors and possessing great definition and distinctness. Such a composite image may be greatly enlarged or amplified by projection, on account of its great degrees of definition. Certain objects will be scanned more accurately in the horizontal direction, while certain others will be scanned more accurately in a vertical or diagonal direction. By combining both horizontal, vertical and diagonal directions in scanning a degree of accuracy or definition is attained that is much in excess of that attained by the mere superposition of images. I may project its light by means of R solely in red light, while Y may be in yellow light, B in blue light and V in violet light. 7

It is well to state again that Figure 3 may be regarded as a representation of a transmitter in which S may be regarded as the object which is scanned in diiferent directions by R, Y, B and V. The resultant four image-varied currents are separately transmitted and received separately and amplified. Wires I5 and 'I carry one of the amplified currents to the lamp or photoelectric cell i. Each of the other lamps or photoelectric cells are shown with separate circuits. They may be supplied by two circuits of the type shown in Figure 2 as illustrated in Fig. 8. In such case two of the lamps or photoelectric cells I and 3 would operate upon one circuit each receiving a specific component of the alternating current, while the remaining lamps i and 5 are operated on another circuit, or they may be arranged according to the system indicated by Figure 4, which employs a special spacing of the lenses or apertures on the disk D, as illustrated in Fig. 9. If four elements are used then the holes should be four times as far apart as ordinarily.

It will be noted that four lamps when placed 45 degrees apart, take up exactly half of the circumference of the disk. The other half of the circumference of the disk may be occupied by four photoelectric cells and their optical systems for scanning an object in four different directions and converting the light into four image-varied currents. Thus a two-way television apparatus would result that utilizes the entire circumference of the disk. Such an arrangement is illustrated in Figure 10, where l, 3, d and 5 designate the glow lamps projecting the received image upon screen S, while lo, 30, lo and 5c designate photoelectric cells which scan the object Ob.

The object Ob may be the observer and the photoelectric cells may be disposed adjacent the opposite face of the disk in order to scan the observer while he views the screen S.

Another modification would include the disposing of photoelectric elements whether glow lamps or photoelectric cells throughout the entire circumference of the disk. This would produce a composite image made up of many separate images scanned in different directions, and containing as many lines as there are lenses on the disk multiplied by the number of image translators (photoelectric cells at the transmitter and glow lamps at the receiver). For instance, if a 60 lens disk and eight glow lamps or photocells, or the like, are used, then there would be 60 times 8 or 480 lines in the composite image. In Figure 3, for instance, the image translator B, would, following out the description, if the disk is revolving clockwise, scan directly opposite to B. That is, B would bring about a scanning as shown at I), wherein the lines are drawn from top to bottom and follow a line sequence from left to right, while a translator 180 degrees removed from this (directly to the left), would draw the lines from bottom to top and follow a line sequence from right to left. As all of the component images would be scanned simultaneously, there would be no flicker, even at quite low speeds, in the resultant composite image. Moreover, if eight component images were used, different portions of the component images would be scanned simultaneously, producing a composite image absolutely free of flicker, as any particular area of the image field in which one component image would be fading, would be rescanned by one or more other component images, even at speeds too low for the presistance of vision effect in ordinary scanning.

In all of the other figures of the drawings but two photoelectric elements l and 3 are shown, but itis to be understood that four or more may be used as desired.

Figure 4 illustrates a modification wherein the same image current is carried by the conductors 6 and. I to the neon lamps I and 3. The result is that both lamps vary their intensity in synchronism. However, the lenses 2 or apertures on the disk D are spaced twice the usual distance apart, i. e., instead of being placed an image width apart, they are placed two image widths apart. The result is that the lenses are so spaced that only one image area is traversed by a lens at any one time. It will be noticed that a lens is just leaving the image area at lamp 5, while a lens is just commencing to scan the image area at lamp 3. Thus but one lamp can have its light projected upon the screen S at any one time. a indicates that image produced by the lamp 1 was scanned horizontally, while 0 indicates that the image produced by the lamp 3 was scanned vertically. The two were exactly superposed to form a composite image.

It will be noticed that in all of the figures so far described, the images have been scanned either simultaneously or in an intercalated manner. That is, a line of one image is scanned, then a line of another image, and so on. The result is a composite image that is composed of two or more interwoven images. Figure 5 illustrates a means of scanning an entire half of an image in one direction, then scanning half of another image in the opposite direction, then scanning the remaining portion of the first image an dthen the remaining half of the second image. Wires 6 and I carry the image varied current and supplies the two lamps l and 3, their light thus varying in synchronism. The light of i and 3 is projected upon the screen S in the manner already described. One image is scanned in the direction indicated by the arrow a and the other indicated by the arrow C. The disk D diners from the ordinary disk in that the apertures or lenses 2 are arranged in two groups disposed at opposite portions of the disk D. Those groups constitute two halves of the spiral. It will be noticed that the upper half of the spiral is just about to finish the scanning of the image area at lamp 1; It has just scanned half of the image in the horizontal direction. This group of lenses is now about to enter the image area of the lamp 3 when it will scan one half of the corresponding image in the vertical direction. When it has finished scanning this half, the group e will have reached the image area at lamp 1 and will scan the remaining half of the image in the horizontal direction. This group will then scan the remaining half of the image in the vertical area. Thus, instead of a line of each image being scanned at any one time, an entire half of an image is scanned.

Figure 6 illustrates another means of scanning an image or images in an intercalated manner; The disk D carries the usual lenses 2 arranged in a spiral line. The light of lamp 2 is projected upon the screen S and the image is scanned in the direction of the arrow a. The image varied current is led in by means of the conductors 5 and i. On the same shaft with the disk D is the commutator K whose body is made of metal or other conducting material. This is provided with teeth making contact alternately with the brushes 8 and t. The spaces between the teeth may be filled with nonconducting material, such as mica, Bakelite, pitch, etc. It will be seen that the current is conducted by t to contact brush (1 to the commutator body. It is shown as being conducted by brush s to lamp Z from whence it returns to the external circuit by conductor 1. In a position of the disk, lamp 1 will be actuated and will scan a line in a horizontal direction. Brush t is on an insulated portion of the commutator and does not make electrical contact in the position of the disk shown. However, in the next instant, brush s will be on an insulated segment and brush t will be on a conducting segment or tooth of the commutator and the current will be diverted to the lamp 3 and a line will be scanned as indicated by the dotted arrow 0. fhus the two component images will be scanned intercalatedly. It is also to be noted that the disk when used in this manner may have onehalf the number of holes or lenses, as only one image is focused at a time, the lens shown in the other image apertures is unnecessary. The

disk is shown in Fig. 6 as having the full number of lenses more particularly for use in combination with Figure '7, as will be described later. The full number of lenses, of course, is also used with several other modifications illustrated in other figures of the drawings. This arrangement has the advantage that all of the image varied current is supplied to but one lamp at one time. Commutating means of different degree may be used to cover all modifications of scanning from line for line intercalated scanning all of the way up to complete scanning of each component image in succession. The last modification alone will be illustrated. This is the arrangement that would be produced by combining or rather sub- 9 stituting the commutator shown in Figure 7 for that of Figure 6. Instead of directly mounting the commutator on the same shaft as disk D in Figure 6, a gear wheel 12 is mounted upon the shaft. This meshes with wheel 9 which is mounted on the same shaft with the commutator K. This modification of the commutator is provided with an insulating surface extending over one half of the circumference of the commutator. The image-varied current enters by conductor 6 and is supplied to the commutator K by brush (2. It is supplied thence to the contacting brush 8 to lamp 1, the opposite brush being on an insulating segment. The wheels 10 and q are so proportioned that 12 makes two revolutions to one of q. Disk D and wheel P are fixedly mounted upon the same shaft and therefore make the same number of revolutions. It will be therefore seen that during one revolution of the disk D, 15 will make contact with the commutator K and consequently 3 will be supplied with the image varied current, and an entire image will be scanned in the direction of the arrow 0. During the next revolution of the disk, brush 3 will be in contact with the commutator K and lamp 1 will be actuated, and as a result an entire image will be scanned in the direction of the arrow at.

a The arrangement shown in Figure 5 also may be modified to cover the various degrees of scanning ranging between that shown in Figure 4, which covers line for line, intercalated scanning to that by which entire images are scanned successively in different directions.

The arrangements shown illustrate some of the many modifications that the invention may assume, and it is not my desire to be limited to any one of them.

The great utility of the invention is shown by the fact that a simple Nipkow disk may be used to produce an image possessing an enormous degree of detail. Instead of the disk, cylinders, bands, tapes and the like may be used, as they are all considered as equivalents in the present state of the television art.

By means of this invention, the broadcasting station might scan images in various directions and broadcast them as indicated by Figure 3. This composite image consisting of the various component images would still be available to the amateur who wished to receive it in the usual manner, i. e., by use of the single neon lamp I. Still other armatures might only be able to aiford two photoelectric elements, such as l and 3, and would receive an image possessing twice the amount of detail as the former. Others could use three and four photoelectric elements. The invention therefore, possesses a great degree of detail of universality.

H desired the images may be projected juxtaposed to each other, instead of superposed. Thus in Figure 1, two images would be placed side by side in the receiver and at the transmitter, two scanning elements R and B would scan objects side by side. If four were used, they could be arranged two above and two below, all juxtaposed. This could be accomplished by simply changing the direction of the projecting means R, Y, B and V (of Figure 4). Each projecting means would then .cover a different section of the composite image, instead of the entire image as in the first described arrangement. The use of the means described in the above application now U. S. Patent No. 2,146,937, issued Feb. 14, 1939, whereby each line scanned by a lens 2 is broken up into several parallel lines, is highly desirable with this invention whether the images are superposed or juxtaposed, It is to be noted that the same apparatus could readily be converted from a superposed to a juxtaposed arrangement and vice versa by simple adjustments.

It is to be noted that in the event that the multiplex scanning of the above mentioned application be used, that instead of projecting each component image exclusively in one color, each image could be projected in all colors by simply coloring each of the prisms, or cylindrical lenses a definite elementary color. Thus, when a single line is broken up into say three parallel lines, by coloring for instance the prisms (such as d, e, and f of the above application) red, yellow and blue, or any other complementary colors, an image in natural colors could be obtained.

Having described my invention, I claim as new and desire to secure by Letters Patent:

1. A scanning apparatus consisting of a single rotating element, a plurality of optical elements suitably arranged in a single image exploring group on said rotating element, a plurality of electro-optical elements cooperating with said optical elements at points forty-five degrees apart on the circumference of said rotating element, the axis of said group of optical elements forming angles differing by 45 degrees with the vertical axis of each of said electro-optical elements, to produce a plurality of images scanned in diiferent directions, means in cooperative relation with said electro-optical elements for superposedly projecting said images, and a screen upon which said images are superposedly projected to produce composite image.

2. A scanning apparatus consisting of a Nipkow disk, a plurality of eleotro-optical elements coopcrating with different portions of said disk to produce a plurality of images scanned in diiierent directions, means in cooperative relation with said electro-optical elements for superposedly projecting said images, and a screen upon which said images are projected superposedly to form a composite image.

3. A scanning apparatus consisting of a single rotatable element, a plurality of optical elements arranged in image exploring relation on said rotatable element, a plurality of image areas disposed at different points adjacent the periphery of said rotatable element, the vertical axes of said image areas being parallel, said optical elements being so arranged on said rotatable element as to traverse said image areas at difierent angles, a plurality of electro-optical elements in cooperative relation with said optical elements and with said image areas to produce a plurality of superposable images each of which is scanned in a direction different from that of its neighbor and means for combining said images into a composite image.

4. A scanning apparatus consisting of a single rotatable element, a plurality of optical elements suitably arranged in image exploring relation on said rotatable element, a plurality of image areas disposed at different points adjacent the periphery of said rotatable element, the vertical axes of said image areas being parallel, said optical elements being so disposed on said rotatable element that but one of said optical elements traverses any of said image areas at any instant, said optical elements being also so arranged on said rotatable element as to traverse said image areas at different angles, a plurality of electro-optical elements in cooperative relation with said optical elements and said image areas to reproduce a plurality of superposable images each of which is scanned in a direction difierent from that of its neighbor and means for forming said images into a composite image.

5. A scanning apparatus consisting of a single rotatable element, a plurality of optical elements arranged in image exploring relation on said rotatable element, a plurality of image areas disposed at different points adjacent the periphery of said rotatable element, the vertical axes of said rotatable element being parallel, said optical elements being so arranged on said rotatable element as to traverse said image areas at different angles, a plurality of glow lamps in cooperative relation with said optical elements and with said image areas and supplied with image varied current to reproduce a plurality of superposable images each of which is scanned in a direction diferent from that of its neighbor, said glow lamps and said image areas being disposed at points ninety degrees apart adjacent said periphery and means in cooperative relation with said glow lamps and said image areas for superposedly projecting said images and a screen upon which said images are superposedly projected to form a composite image.

6. A scanning apparatus consisting of a single rotatable element, a plurality of optical elements suitably arranged in image exploring relation on said rotatable element, a plurality of image areas disposed at difierent points adjacent the periphery of said rotatable element, the vertical axes of said areas being parallel, said optical elements being so arranged on said rotatable element as to traverse said image areas at different angles, a plurality of glow lamps each projecting a light of different color in co -operative relation with said optical elements and with said image areas to produce a plurality of difierently colored superposable images scanned in different directions, means in cooperative relation with said glow lamps and with said image areas for superposedly projecting said images and a screen upon which said images are superposedly projected to produce a composite image in natural colors.

7. A scanning apparatus consisting of a single rotatable element, a plurality of optical elements arranged in single image exploring relation on said rotatable element, a plurality of image areas disposed at difierent points adjacent the periphery of said rotatable element, the vertical axes of said areas being parallel, said optical elements being so arranged on said rotatable element as to traverse said image areas at different angles, said optical elements being spaced apart on said rotatable element a distance equal to a multiple of the width of each of said image areas also equal to a multiple of the width of a glow lam-p associated with each of said areas in order that said optical elements may alternately traverse said image areas, a plurality of glow lamps in cooperative relation with said optical elements, and so spaced that but one of said optical elements cooperates with but one of said glow lamps at any instant and with said image areas to produce a plurality of superposable images scanned in different directions, means in cooperative relation with said glow lamps for superposedly projecting said images and a screen upon which said images are superposedly projected to produce a composite image.

8. A two-way television apparatus consisting of a single rotatable element, a plurality of optical elements arranged on said rotatable element in image exploring relation, a plurality of image areas at different points adjacent the periphery of said rotatable element, the vertical axes of said areas being parallel, said optical elements being so arranged on said rotatable element as to traverse said image areas at different angles, a plurality of electro-optical elements in cooperative relation with said optical elements and with certain of said image areas each of which is scanned in a direction different from that of its neighbor, means in cooperative relation with said electrooptical elements and said image areas for superposedly projecting said images, a screen upon which said images are superposedly projected to form a composite image, means for forming images of televisable objects in the remainder of said image areas and a plurality of photoelectric elements in cooperative relation with the light of the images in said image areas to produce corresponding image varied currents from images scanned in different directions.

ALOYSIUS J. CAWLEY.

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