DE2120881A1 - Multiple electron beam scanner - Google Patents

Description

The present invention relates to an electron beam scanner and in particular a scanner that uses flat dynode controls and a modulation dynode used and sie suitable for high-jet operation.

In the ü. See Patent Ho. 3 »408,532 by D. E. Hultberg et al. that of liorthrop Corporation, the assignee of the present Registration, granted, is an electron beam scanner which a number of encoded in stripe patterns Dynode elements used in sandwich construction between an electron-emitting cathode and a collecting electrode trode are provided and the two are independent of each other contain conductive sections arranged in a striped pattern (finger-like oyster) are arranged. The openings in the Dynodes are aligned with each other so that they: Electron-. Form beam channels leading from the cathode to the collecting electrode get lost. The conductive sections of the dynode striped pattern

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Patent attorneys Dipl.-lng. Martin Licht, Dipl.-Wirtsdt.-Ing. Axel Hansmann, Dipl.-Phys. Sebastian Herrmann

8 MDNCHEN 2, TH ER ES I EN STRASS E33 · Telephone; 281202 Telegram address: Upatli / Munich Bayer. Vereinsbank MBndien, Zwei _O (t. Oskar-von-Miller-Ring, Klo, -Nr. 8B2495Poslicheck-Account: MOndien Nr. 163397

Oppenau office: PATENT ADVOCATE DR. REINHOLD SCHMIDT

are energized according to binary control signals so that respectively one of the channels is activated j thereby can; the beam deflect it onto the collecting electrode in a predetermined manner.

There are certain advantages to working with multiple beams, the simultaneously different sections of the collecting electrode an electron beam scanner according to; Kind of in that mentioned Patent besohriebefien device scan: * Firstly, can through such a blasting operation several at the same time generate separate advertisements. In this way, the information tion processing capacity of the scanner can be increased. In addition, the various beams can be used to display different sections of the same display at the same time. With a television picture, for example, you can different sections of this image at the same time on the Register the screen, with the eye assembling the overall picture from these various individual sections. These Type of simultaneous beam scanning has the advantage that each of the simultaneously scanning beams for a given one Total scan time can scan more slowly what the beam a longer dwell time with each dissolution element of the Catching electrode allowed and thereby the image brightness increased.

The device of the present invention has compared to the the above patent made an amendment to an operation allows each of the rays to be separated according to *! modulation s-Steueraignalen can be excited. Obviously the device according to the invention can except for image reproduction also be designed as an image sensor or as a storage device, to scan a number of separate images or patterns, or save.

The device according to the invention is very similar to that Single beam ^ Abtas% erät that in the mentioned patent Ko *

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3,408,532. Ea contains a relatively simple one Modification of the arrangement described in the patent. This U.S. patent is therefore incorporated herein by reference Application included, whereby, as is apparent to those skilled in the art, only the information going beyond the presentation of the patent is here is explained in more detail.

The invention is essentially based on the object based on 'an improved electron beam scanner' Kind of it in the TJ. S. Patent Uo. 3,408,532 devices described to. “that can be used for multi-beam operation.

The invention can be summarized as follows: A number of flat, coded dynode elements are provided in a sandwich construction between an electron-emitting cathode designed as a flat plate and a flat collecting electrode. The dynode elements include openings that aind so aligned _r that they form through all SYNODS .hindurchlaufende Elektronenetrahlkanäle. Each of the dynodes also contains independently conductive stripe patterns, the finest stripe pattern defining a pixel on the collecting electrode. The stripe patterns and the number of synods used are chosen so that they form a certain number of simultaneously scanning beams. An ilodulation grid with openings which correspond to the dynode openings and with separate sections which cover the surface areas which each of the scanning beams covers is located between the cathode and the collecting electrode and controls the excitation of the beam.

There now follows a description of the invention with reference to the drawing. The schematic drawing explains an - execution s example of the device according to the invention. The present invention comprises a cathode formed as a flat plate and the like

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212Q881-.

a flat collecting electrode, between which a number of control plates or dynodes are located in Sändwiöh-Bäüweise, which serve to control several electron beams * It should be mentioned that the control plates do not need to be electron multipliers or dynodes align and thereby form electron beam channels - which run from the cathode to the collector. The dynodes contained in a particular stripe pattern arranged control electrodes ^ wherein the fine stripe pattern _r represents a pixel of the Äuffangelektrode * The stripe patterns are selected and arranged so that simultaneously a plurality of scanning beams P to be created. Switch devices are provided for the dynodes in order to be able to selectively excite the electrode strip patterns, so that each beam activates a single ^ scanning element. Separate control electrodes are provided on a modulation grid with openings that are aligned with the dynode openings, with each electrode controlling one beam at a time.

A preferred embodiment example is schematically shown in the drawing of the invention shown. This execution example contains four separate rays, where each of the rays: can scan one quadrant of the collecting electrode at a time. ^ Obviously the use of four rays is one

. special application example of general Liehrstrahl operation. By other combinations of striped electrodes and Number of dynodes can be various other beam arrangements create. - ,,.;

Between the cathode 16 and the collecting electrode 11 there is a " Power supply 33 to accelerate the flow of electrons. Between the cathode and the collecting electrode there are dynode • elements 22-26. As in the Uo patent. 3,408,532 is described, Are the cathode, the collecting electrode and the dynode

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elements in a vacuum. The dynodes have openings 47 which are arranged in a similar matrix pattern in all dynodes are. The dynodes are aligned with one another so that corresponding openings between the electron beam channels Cathode and the collecting electrode form.

The dynode 22 includes conductive portions 22a and 22b on two opposite faces. These conductive sections are insulated from each other and with the opposite steps a flip-flop 50 connected. Included in a corresponding manner the dynodes 23-25 conductive portions 23a, 23b-25a, 25b connected to respective flip-flops 51-53. The modulation dynode 26, which forms a control grid, includes four separate electrode segments 26a-26d on opposite ones Plate surfaces. Each of the segments 26a-26d receives its own modulation signal from an associated modulator unit 60-63.

As detailed in the referenced patent, the electrodes 22a, 22b-25a, 25b arranged in a striped pattern can be selectively used by their associated flip-flops 50-53 are excited in order to control the electron beams between cathode 16 and collecting electrode 11. With the one mentioned in that The device described in the patent can only excite a single elementary section of the collecting electrode at a time. while in the case of the present device, four of these are more elementary Sections are excited at the same time. Such a simultaneous multi-beam operation is shown in the drawing Embodiment thereby enables the dynodes provided in the mentioned patent with only two Strip electrodes are omitted and a kodulationsdynode 26 is additionally used for the control each of the beams has separate electrode sections 26a-26d.

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In the drawing, the strip electrodes 22a-25a are not "* dotted, which means "that these stripes are forward biased by their respective flip-flops to cause electron flow. the Stippled or punctured electrodes 23b-25b are reverse-biased biased to retard the flow of electrons. If so, each quadrant 26a-26d of the modulation dynode 26 in the forward direction is biased, can be seen to achieve four beams 6Oa-6Od the collecting electrode 11. The electron flow through all other channels, for example beam 61, is repelled at one or the other dynode. He- obviously, proper operation of the I'lipflops 50-53 each segment of the collector through the associated one Beam are selectively excited so that it is scanned either regularly or in any manner.

Each modulator 60-63 delivers to the associated control electrode section 26a-26d modulated intensity signals, whereby four image reproductions can be generated on the collecting electrode, each of which is assigned to a separate modulation signal. As already mentioned, these four image reproductions can be combined into a single image; however, it can also four separate representations are shown.

W It can be seen that different numbers of beams and beam pattern arrangements with the aid of the dynodes may be created so that the desired results can be achieved with corresponding stripe patterns in conjunction with a suitable Modulationsdynode. For example, an eight-beam scanner can be created by eliminating dynode 22 and using an eight segment modulating dynode.

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Obviously, the device shown in the drawing is used with 8x8 channels only for explanation »because devices in practice would normally contain significantly more channels. Farther it should be mentioned that in certain cases it may be useful Electron multiplier dynodes that are always in the forward direction are biased to use, especially when only a few control dynodes to generate a relatively large number of beams be used.

The device according to the invention thus creates a simple and yet highly sensitive device for sweeping operation of a ■ Electron beam scanner, these individual beams being modulated separately.

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Claims (4)

PATENT CLAIMS 1.) Electron beam scanner with multiple beams, characterized by a flat plate cathode (16)} a flat plate collecting electrode (11)} several control plates (22-26), which are sandwiched between the cathode and the collecting electrode and control the flow of electrons, each control plate contains openings (47) and wherein corresponding openings of the individual control plates are aligned with each other to form electron channels between the cathode and collecting electrode} electrodes (22a, 22b-25a, 25b), which are on the control plates in certain, paired fringe patterns are disposed} switch devices (50-53)> to "bias the a ⁷ or other strip pattern pair alternately in the forward direction, to activate for each of the beams at any given time depending on a single separate channel, and modulation means (26) between the cathode and the collecting electrode to modulate each of the beams individually. 1U9847 / 1 662 2. Scanner according to claim 1, characterized in that the Modulation device includes openings corresponding to the openings of the control plates, and wherein electrode elements are provided on the modulation device, each of which the electrode elements are used to control one of the beams. 3. The scanner of claim 2, further characterized by Devices (61-63) to modulate signals for each of the To create electrode elements. 4. Scanner according to claim 3, characterized by four beams, wherein the modulation device (26) has four electrode elements (26a-26d) each comprising a quadrant of the modulation device, each striped pattern contains at least two strips. 109847/16 62 Blank page