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Publication numberUS2345080 A
Publication typeGrant
Publication dateMar 28, 1944
Filing dateMar 24, 1941
Priority dateFeb 19, 1940
Publication numberUS 2345080 A, US 2345080A, US-A-2345080, US2345080 A, US2345080A
InventorsArdenne Manfred Von
Original AssigneeArdenne Manfred Von
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Arrangement for producing filters
US 2345080 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

March 28, 1944. M, VON ARDENNE ARRANGEMENT FOR PRODUCING FILTERS Filed March 24, 1941 4ft orney,

Patented Mar. 28, 1944 ARRANGEMENT FOR PRODUCING FILTERS Manfred von Ardenne, Berlin-Hcliteflelde, Gelmany; vested in the Alien Property Custodian/ '5 Application March 24, 1941, Serial No. 385,034 3 v In Germany February 19, 1940 v ,j

7 Claims.

This invention relates to an arrangement for producing filters.

To produce surface filters and ultra-filters which have the properties of an ideal filter it is known in the art to burn in a foil with the aid of ion rays perforations of constant magnitude and form and in a desired spaced relation from one another.

The object of the present invention is to provide an arrangement, whereby the greatest possible number of very fine perforations are burnt in a filter film so as to reduce the filter resistance (resistance to flow). This may be accomplished according to the invention by the fact that the cross-section through which pass the ion rays issuing from the ion emitting source is projected by means of an electrostatic multiple lens on the foil to be perforated. To this end, a short focus multiple lens is preferably employed in front of the foil. By providing the electrostatic multiple lens with a plurality of accurately aligned perforations, it is also possible to burn when producing filters a corresponding plurality of perforations in the foil. In carrying the invention into practice a multiple lens is preferably employed consisting of two electrodes impressed with a high negative potential and provided with a plurality of perforations and of an electrode interposed between these two electrodes and impressed with a lower negative potential and also provided with perforations.

Since the distance between the individual elements of the multiple lens is relatively great, perforations are obtained in the foil during the buming operation between which there may be relatively broad stripes of the foil which are not perforated. In order to provide also these stripes with perforations to the greatest possible extent, the arrangement according to the invention is so designed that the ion rays may be deflected after the first burning operation by means of deflecting magnetic fields in a corresponding manner.

A further possibility of increasing the number of perforations obtainable with one burning operation consists according to the invention in the fact that the ion emitting source is provided in a known manner with two electrodes having a plurality of perforations which form a plurality of cross-sections for the passage of electron rays. By means of the multiple lens not only a single ion ray cross-section but a plurality of ion ray crosssections are therefore projected simultaneously.

In the accompanying drawing, Fig. 1, is shown an embodiment of the invention in diagrammatic form. The reference numeral i denotes a canal ray tube in which is arran'gedfanfloidde-coated incandescent cathode 2.1 Directly infront of the incandescent cathodearetwoseries-arranged electrodes. canal." Theselielectrodes are each provided with a pluralijtyiof accuratel aligned perforationst and 6;,'respectively.' These electrodes are spaced frpmjeachother adistance of about 3 mm. .;Thelelec't'rode 3j may, for instance, be impressed'witlila voltageof +40. volts and the electrode 4 with a voltagegof 520,000 volts. Hydrogen at a pressure 'oflifi' millimeters Hg may be supplied to thfe tubeq' The ,arclgas discharge resulting therefrom may, for instance, burn at a potential of 40 volts; Injthis known arrangement an ion emitting source is providedby means of which a plurality of fine; ion rayso'rresponding to the numberlof perforationsj and 6 is produced. The 'referencehuiiierals 8, 9 denote an electrostatic short .focus multiple lens which serves to projectthe numerous cross-sections for the passage of theion rays" on a foil l4 arranged directly behind the multiple lens. To this end, the foil It is, stretched onacar'rier ii. The three electrodes of the multiple lens areeach provided with a plurality of perforations 10,1 and 12. In this manner a numberofelements of the multiple lens are obtained icorresponding to the number of the perforations. The central electrode l is, for instance, impressed with a potential of 5,000 volts, whereas the other two electrodes 8 and 9 with a potential of 20,000 volts.

In the operation of the device a plurality of fine ion rays are emitted at the openings 6 of electrode 4, as previously mentioned. These rays are so formed, due to the potential on the electrode 4. that each ray has a sufficiently large cross-section in the plane of the electrostatic multiple lens 1-9 to cover the entire area of the lens. Thus the ions composing small sections of each ray enter the openings H of the front electrode 8 of the multiple lens 1-9. Looking at it from the standpoint of the multiple lens, each individual lens thereof receives a plurality of ion ray sections, which are parts of the ion rays emitted from the plurality of openings 6, respectively. The ray sections received by each individual lens are affected by the lens potential in known manner and are focused on the foil l4, whereby perforations are burned in the foil. In this connection, it may be pointed out that since each ray section received at an individual lens reaches the lens from a different direction from the directions of the other ray sections, these ray sections are focused at different points on the foil l4, and the perforaticn pattern producedat the foil is a reproduction oi the opening pattern at electrode 4, although much reduced in size.

In llig. 2 is shown a top view of a portion of the foil film it provided with perforations obtained by the burning process. The reference numerals l1, l8, l9 and I denote fields of filter perforations, each produced by one element of the multiple lens. Each perforation in such a field corresponds to the projection of a corresponding perforation in the electrodes 3 and 4 of the electron emitting source as above explained.

Since from a constructional point of view the distance a between the individual fields of the perforations produced by each element of the multiple lens is great in proportion to the width b or the field, also the portions of the foil not yet provided with perforations may be perforated by the use of electrostatic deflecting fields which may be, for instance, produced by deflecting plates is and it which deflect the ion rays in a known manner. With the aid of the above-described arrangement the greatest possible number of fine, nay ultra-microscopic filter perforations may be attained. Assuming, for instance, that in the electrode 4 there are one hundred perforations of a diameter of 0.5 mm. and that the electrostatic multiple lens has 50 perforations, 5,000 periorations are obtained at the same time in the filter foil with one burning operation.

When carrying the invention into practice it is particularly advantageous to use such ions which react with the filter substance. This is, for instance, the case when employing oxygen and pyroxylin foils.

What is claimed is:

1. An arrangement for producing filters, where'- by fine perforations are made in a foil by means of ion rays, comprising a source of ions, an electrostatic multiple lens for forming a plurality of overlappin ion beams, and a second electrostatic multiple lens arranged to produce a plurality of ion beams from each of said first mentioned beams and project them on the foil to be perforated.

' 2. An arrangement for producing filters, whereby fine perforations are made in a foil by means of ion rays. comprising a multiple electrostatic lens for projecting ions on to the foil to be perforated, a source of ions, and a second multiple electrostatic lens for directing a plurality of beams of ions toward said first multiple lens, the firstmentioned of said multiple electrostatic lenses receiving in each of its individual lenses a part of each of said beams of ions whereby each of said individual lenses directs a pattern of individual beams composed of individual parts or each of said beams.

3. An arrangement as set forth in claim 1, wherein the projecting lens comprises three spaced electrodes having aligned perforations therein, the two outer electrodes being impressed with a high negative potential and the central electrode with a lower negative potential.

ad/Anarrangelhent according to claim 1, where in the ionsiare produced from a gas whichis capable of reacting with the toil.

5. Apparatus for producing fine perforations in a foil or the like, comprising a source of ions, means cooperating with said source to form a plurality of ion rays which have overlapping cross-sections in a given plane, and a multiple lens located substantially in said plane, said lens comprising a plurality of individual lenses each operative to receive a section of each oi said ion rays and focus such sections at different points, respectively, on said foil.

6. In apparatus for producing filters by making perforations in a foil by means of ion rays, means constituting a source of a plurality of individual beams having overlapping cross-sections with the central axis of all of the beams substantially parallel but with the rays forming each beam out of parallel relationship, and a multiple lens assembly positioned in the path of said beams comprising a plurality of individual lenses each of which is operative to receive a section of each of said beams and direct the sections at diiferent points respectively on the foil.

7. Apparatus as described in claim: 6 wherein deflectors are provided at the sides of the path of the beams for producing a field to defiect the beams.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2741719 *Sep 27, 1950Apr 10, 1956Rauland CorpMethod and apparatus for inscribing a pattern in a target electrode structure
US2778926 *Sep 4, 1952Jan 22, 1957Licentia GmbhMethod for welding and soldering by electron bombardment
US2793281 *Nov 28, 1951May 21, 1957Zeiss CarlDrilling by electrons
US2793282 *Nov 28, 1951May 21, 1957Zeiss CarlForming spherical bodies by electrons
US2819380 *Mar 23, 1953Jan 7, 1958Du Mont Allen B Lab IncMethod and apparatus for making apertured masks
US2842694 *Nov 4, 1952Jul 8, 1958Licentia GmbhChi-ray apparatus
US2945143 *Apr 3, 1958Jul 12, 1960Shapiro JackCompact cathode ray tube
US3009050 *Feb 18, 1957Nov 14, 1961Zeiss CarlElectron beam means for initiating chemical reactions
US3155460 *May 20, 1960Nov 3, 1964Norman B MearsFine mesh screens
US3294954 *Oct 15, 1963Dec 27, 1966Harnischfeger CorpWelding method and apparatus
US3438504 *Aug 11, 1966Apr 15, 1969Gen ElectricFilter element and method of production
US3482703 *Jan 30, 1968Dec 9, 1969Brunswick CorpParticulate and biological filters
US3534385 *Dec 6, 1966Oct 13, 1970Centre Nat Rech ScientProcess and apparatus for micro-machining and treatment of materials
US3805106 *Apr 14, 1972Apr 16, 1974Gen ElectricElectrostatic fly{40 s eye lens
US3895602 *Feb 14, 1974Jul 22, 1975Thomson CsfApparatus for effecting deposition by ion bombardment
US4224523 *Dec 18, 1978Sep 23, 1980Xerox CorporationElectrostatic lens for ink jets
US4855049 *Nov 14, 1988Aug 8, 1989Commissariat A L'energie AtomiqueMicroporous membrane obtained by the irradiation of two faces and process for obtaining the same
US5308180 *Dec 4, 1992May 3, 1994Minnesota Mining And Manufacturing CompanyLiquid applicator with metering insert
EP0317399A1 *Nov 10, 1988May 24, 1989Commissariat A L'energie AtomiqueMicroporous membrane and method of preparing by irradiation on both sides
U.S. Classification250/398, 313/599, 219/69.17, 313/230, 164/DIG.400, 219/121.12, 315/16, 313/360.1, 219/121.26, 210/498
International ClassificationH01J37/12, H01J37/31, H01J37/30, H01J37/08
Cooperative ClassificationH01J37/08, H01J37/12, Y10S164/04, B01D67/0032, H01J37/31
European ClassificationB01D67/00K18F, H01J37/08, H01J37/31, H01J37/12