Electron-diffraction apparatus

Claim 1

IN AN ELECTRON DIFFRACTION APPARATUS FOR PRODUCING AN IMAGE OF AN OBJECT DISPOSED IN THE PATH OF AN ELECTRON BEAM ON A LUMINESCENT SCREEN AND ON A PHOTOGRAPHIC PLATE, RESPECTIVELY, INCLUDING AN EVACUATED CHAMBER, MEANS WITHIN SAID CHAMBER TO GENERATE AN ELECTRON BEAM, MEANS TO SUPPORT THE OBJECT IN THE PATH OF THE BEAM, MEANS TO PROJECT AN ELECTRON IMAGE OF THE OBJECT ONTO THE LUMINESCENT SCREEN AND PHOTOGRAPHIC PLATE, RESPECTIVELY, AND MEANS TO ALTERNATELY POSITION SAID LUMINESCENT SCREEN AND SAID PHOTOGRAPHIC PLATE IN THE PATH OF SAID ELECTRON BEAM TO REPRODUCE THE PROJECTED IMAGE OF SAID OBJECT, SAID LAST MEANS INCLUDING A SUPPORT FOR SAID LUMINESCENT SCREEN COMPRISING A FLAT CIRCULAR PLATE HAVING A CENTRAL AXIS COINCIDENT WITH THE ELECTRON BEAM, A CENTRALLYDISPOSED PIN MEMBER HAVING A GIVING AXIS, AND CONNECTED TO SAID PLATE AND EXTENDING REARWARDLY FROM SAID PLATE THROUGHT AN APERTURE IN A WALL OF THE VESSEL, MEANS OUTSIDE SAID VESSEL TO ROTATE SAID PIN MEMBER ABOUT SAID GIVEN AXIS AND TO MOVE SAID PIN MEMBER ALONG SAID GIVEN AXIS, A DISPLACEABLE HOLDER FOR SAID PHOTOGRAPHIC PLATE DISPOSED ADJACENT SAID SUPPORT FOR SAID SCREEN, MEANS INTERCONNECTING SAID FLAT CIRCULAR PLATE AND SAID PHOTOGRAPHIC PLATE HOLDER AND ADAPTED UPON ROTATION AND DISPLACEMENT OF SAID PIN MOVE SAID HOLDER TRANSVERSE TO SAID GIVEN AXIS OF SAID PIN INTO THE POSITION PREVIOUSLY OCCUPIED. BY SAID ROUND PLATE FOR THE TAKING OF A PHOTOGRAPH.