Albada viewfinders with molded lens and plane mirror for viewing indicator element

Claim 1

IN A BLOCK TYPE ALBADA VIEWFINDER FOR PHOTOGRAPHIC CAMERAS, INCLUDING A FRONT PLANO-CONCAVE LENS, A CENTRAL LENS HAVING A CONVEX OUTER SURFACE FACING THE CONCAVE SURFACE OF SAID FRONT LENS AND A CONCAVE INNER SURFACE, AN OCULAR HAVING A CONVEX SURFACE FACING THE CONCAVE SURFACE OF THE CENTRAL LENS, A SEMI-TRANSPARENT MIRROR DISPOSED BETWEEN THE ADJACENT SURFACES OF THE FRINT AND CENTRAL LENSES, AND A PICTURE LIMITING FRAME DISPOSED BETWEEN THE ADJACENT SURFACES OF THE CENTRAL LENS AND OF THE OCULAR; MEANS FOR PROVIDING, IN THE FIELD OF VIEW OF AN OBSERVER LOOKING THROUGH THE OCULAR, AN IMAGE OF THE POSITION OF AN EXPOSURE CONDITION INDICATING ELEMENT OF THE CAMERA LOCATED EXTRANEOUS TO THE VIEWFINDER, SAID MEANS COMPRISING A LATERAL PLANE SURFACE FORMED ON SAID FRONT LENS OBLIQUE TO THE OPTICAL AXIS OF THE VIEWFINDER AND FACING TOWARD THE CONVEX OUTER SURFACE OF SAID CENTRAL LENS, SAID LATERAL PLANE SURFACE BEING SUBSTANTIALLY COMPLETELY WITHIN THE LATERAL CONFINES OF THE VIEWFINDER; THE LATERAL EXTENT OF THE CONCAVE SURFACE OF SAID FRONT LENS BEING LESS THAN THE LATERAL EXTENT OF THE CONVEX SURFACE OF SAID CENTRAL LENS BY SUBSTANTIALLY THE DEPTH OF THE RECESS FORMED BY SAID LATERAL PLANE SURFACE SO THAT A PORTION OF THE CONVEX SURFACE OF SAID CENTRAL LENS EXTENDS LATERALLY BEYOND THE CONCAVE SURFACE OF SAID FRONT LENS; A MIRROR ON SAID OBLIQUE LATERAL PLANE SURFACE OPERABLE TO REFLECT THE LIGHT RAYS FROM THE INDICATING ELEMENT TO THE EYE OF AN OBSERVER LOOKING INTO THE VIEWFINDER THROUGH SAID OCULAR AND ALONG THE OPTICAL AXIS OF THE VIEWFINDER; AND IMAGE FORMING OPTICAL ELEMENT IN THE PATH OF LIGHT RAYS REFLECTED BY SAID MIRROR THROUGH SAIS OCULAR, SAID IMAGE FORMING OPTICAL ELEMENT COMPRISING A MOLDED DEPOSIT OF TRANSPARENT SYNTHETIC RESIN ADHERED TO THE PROJECTING PORTION OF THE CONVEX SURFACE OF SAID CENTRAL LENS AND HAVING LIGHT REFRACTING CHARACTERISTICS SUCH AS TO PROVIDE, IN THE FIELD OF VIEW OF SUCH VIEWER LOCKING INTO THE VIEWFINDER THROUGH SAID OCULAR AND ALONG THE OPTICAL AXIS OF THE VIEWFINDER, A SHARPLY FOCUSED IMAGE OF SAID ELEMENT IN ADDITION TO THE SHARPLY FOCUSED IMAGES OF THE SUBJECT TO BE PHOTOGRAPHED AND OF SAID PICTURE LIMITING FRAME; AND A LAYER OF TRANSPARENT SYNTHETIC RESIN COVERING THE OUTER SURFACE OF SAID PLANE MIRROR, SAID OPTICAL ELEMENT BEING INTEGRAL WITH AND FORMING A CONTINUATION OF SAID LAYER.