Show Static Is Cut 1 By New N W Lens Len Radio Waves Are Focused Which Increases Freedom From Interference x NEW NEW YORK A metal lens which focuses a radio wave Into the sharpest beam ever produced produced- somewhat as a glass lens focuses the rays of the sun into a hot beam that can burn a hole in a sheet of paper was paper was disclosed here by the Bell Telephone laboratories as one of its secret wartime developments says the New York Times Operating on a principle roughly akin to that of a simple convex mag mag- magnifying magnifying magnifying glass lens the metal lens lel herds the radio power generated by bya bya a small very high trans trans- transmitter transmitter transmitter mitter into so compact a bundle in space that nearly all aU of the power t can be focused on the receiving 1 collector system or antenna of a distant station thereby greatly in increasing in- in increasing increasing creasing the effect of the sending equipment As a result great freedom is gained from static and man-made man I interference The lens operates atthe at atthe I the exceedingly high frequency of t nearly five billion cycles At such frequencies radio waves are about I as long as an ordinary cigarette Proves Its Efficiency 1 It is difficult to generate large amounts of radio power at such frequencies or wave lengths but I the lens is said to be such an efficient effi effi- efficient efficient piece of equipment that it often j is able to make as little as one- one I tenth of a watt seem to be as great as several kilowatts The shorter the radio waves generated and the larger the device utilized to radiate I them into space the greater Is this multiplying power I The lens that actually creates sev sev- several several several eral kilowatts of power is 10 feet square shaped somewhat like a aJ J large square horn With others of j I the same type it is soon to be util- util utilized I between New York and Bos- Bos Boston Boston I ton on an an intercity communication I link capable of carrying simultaneously I I I several television programs telephone telegraph teletype etc I I The lenses will be installed atop t I j high steel towers spaced about 30 I miles apart between the two cities I The device was designed and nd de de- developed deI de- de I by Dr Winston E. E Kock and associates at the Bell Ben laboratories laboratories' toward the end of the war war so had only a limited application for mili mili- military military tary purposes j i Action of Glass Lens I Similar systems system t however devel- devel developed developed developed j I in secret for use by the armed forces are said to have been found able to give superior and dependable depend depend- dependable dependable 1 able communications under rigorous battle conditions both in Europe and Pacific areas The action of a glass lens is to i slow down the speed of rays go- go goi going going going i i ing through it the thicker the glass the greater the slowing influence I i Hence a double convex lens slows I II the rays nearest its optical center j I Imore I more than those nearer its peri ery Thus the rays can be brought into focus at some point beyond the II lens Radio waves on the other hand gain speed when they are passed I along a metal tube or between flat metal plates A metal lens designed I to equalize the wave front frontI of radio waves and thus concentrate j I I I and make them more effective on a given target is is designed so the waves pass along metal plates or fins that are thinnest near the cen cen- center center center ter of the lens and thicker near the outside edges One of the advantages of the metal lens is that the beam it fo fOe focuses buses on a distant receiver cannot be made to waver when high winds winds' strike the tower on which it is mounted Once adjusted the metal met met- metal metal al lens stays adjusted it is said |