Keratometer with adjustable fixation target attachment for determining corneal topography

Claim 1

IN A DEVICE FOR SURVEYING A HUMAN CORNEA AND INCLUDING A KERATOMETER HAVING A PROJECTING CIRCULAR CELL MEMBER; A FIXED OPTICAL TARGET FOR ESTABLISHING THE VISUAL AXIS OF THE CORNEA; OPTICAL MEANS INTERCONNECTED WITH SAID CELL MEMBER FOR ESTABLISHING AN OPTICAL AXIS COINCIDENT WITH SAID VISUAL AXIS; ILLUMINATING MEANS FOR ESTABLISHING A PAIR OF SPACEDAPART REFERENCE LOCATIONS ON SAID CORNEA EACH SPACED A PRESELECTED DISTANCE FROM SAID VISUAL AXIS; AND MEASURING MEANS FOR DETERMINING THE LENGTH OF THE CHORDAL DISTANCE BETWEEN SAID TWO REFERENCE LOCATIONS ON THE CORNEA; THE IMPROVEMENT IN COMBINATION THEREWITH COMPRISING A SUPPORT FRAME FOR CONNECTION WITH SAID CIRCULAR CELL MEMBER AND HAVING AN OPEN CIRCULAR PORTION TO BE CONCENTRICALLY POSITIONED ABOUT SAID VISUAL AND OPTICAL AXES; FIRST AND SECOND SYMMETRICAL SCALES MOUNTED ON SAID FRAME AT RIGHT ANGLES TO EACH OTHER AND SPACED FROM SAID CIRCULAR PORTION, SAID SYMMETRICAL SCALES EACH HAVING A CENTRALLY LOCATED REFERENCE POINT HORIZONTALLY AND VERTICALLY ALIGNED WITH SAID VISUAL AND OPTICAL AXES; FIRST AND SECOND INDICATOR SUPPORT MEMBERS SLIDABLY MOUNTED ON SAID FRAME FOR RESPECTIVE MOVEMENT ALONG SAID FIRST AND SECOND SCALES FOR INDICATING ON A RESPECTIVE ONE OF SAID SCALES THE POSITION OF EACH OF SAID INDICATOR SUPPORT MEMBERS WITH RESPECT TO SAID OPTICAL AND VISUAL AXES; AND FIRST AND SECOND PERPENDICULARLY INTERESTING INDICATOR ARMS FIXED RESPECTIVELY TO AND PROJECTING FROM SAID FIRST AND SECOND INDICATOR SUPPORT MEMBERS TO ESTABLISH A SELECTIVELY VARIABLE FIXATION POINT OBSERVABLE WITHIN SAID CIRCULAR PORTION OF SAID FRAME AND SELECTIVELY SPACED FROM SAID OPTICAL AXIS FOR DECENTERING SAID VISUAL AXIS OF THE CORNEA FROM SAID OPTICAL AXIS.