Apparatus producing interferential test data for measuring and control instruments

Claim 1

IN AN APPARATUS FOR PRODUCING INTERFERENTIAL TEST DATA FOR MEASURING AND CONTROL INSTRUMENTS, A LIGHT SOURCE, A CONDENSER, A DIAPHRAGM HAVING AN APERTURE, SAID CONDENSER IMAGING SAID LIGHT SOURCE IN SAID APERTURE, A COLLIMATOR LENS MAKING PARALLEL THE DIVERGENT LIGHT RAYS EMANATING FROM SAID APERTURE, IN THE PARALLEL RAY PATH OPTICAL RAY-DIVIDING ELEMENTS SPLITTING SAID PATH INTO THREE PARTIAL BEAMS, SAID THREE PARTIAL BEAMS BEING A MEASURINGRAY BEAM AND TWO REFERENCE-RAY BEAMS, FIRST STATIONARY DEFLECTING SURFACES DISPOSED IN AND DEFLECTING AT LEAST TWO OF SAID PARTIAL BEAMS EMANATING FROM SAID RAY-DIVIDING ELEMENTS, THREE OPTICAL DEFLECTORS, ONE OF SAID DEFLECTORS DEFLECTING SAID MEASURING-RAY BEAM AT LEAST APPROXIMATELY 180* AND BEING CONTINUOUSLY DISPLACEABLE IN THE MEASURING PROCESS, THE TWO OTHER OF SAID DEFLECTORS DEFLECTING RESPECTIVELY SAID REFERENCE-RAY BEAMS AT LEAST APPROXIMATELY 180* AND BEING ALTERNATELY SO DISPLACEABLE IN THE MEASURING PROCESS THAT THE CHANGE IN LENGTH OF THE RESPECTIVE REFERENCE-RAY BEAM IS NO GREATER THAN TWICE THE COHERENCE LENGTH OF THE USED LIGHT, ECH OF SAID TWO OTHER DEFLECTORS BEING EFFECTIVE ONLY WHEN IN POSITION OF REST, A DIAPHRAGM RELATED TO EACH OF SAID REFERENCE-RAY BEAMS AND INSERTABLE INTO AND OUT OF SAID BEAMS, OTHER STATIONARY DEFLECTING SURFACES DISPOSED IN AND DEFLECTING AT LEAST TWO OF SAID PARTIAL BEAMS EMANATING FROM THE RESPECTIVE DISPLACEABLE DEFLECTORS, OPTICAL RAY-FUSION ELEMENTS FOR COMBINING WITH THE MEASURING-RAY BEAM THE EFFECTIE REFERENCE-RAY BEAM, A CONVERGENT OPTICAL COMPONENT FOR PRODUCING IMAGES OF THE INTERFERENCES DUE TO FUSION OF SAID EFFECTIVE REFERENCE-RAY BEAM AND SAID MEASURING-RAY BEAM, A PAIR OF PHOTOCELLS IN THE PLANE OF SAID INTERFERENCE IMAGES, BETWEEN SAID CONVERGENT OPTICAL COMPONENT AND SAID PHOTOCELLS MEANS FOR CAUSING ONE AND THE SAME INTERFERENCE IMAGE WHILE BEING DISPLACED TO SUCCESSIVELY INFLUENCE SAID TWO PHOTOCELLS AND THEREBY TO PRODUCE CURRENT IMPULSES, AN IMPULSE FROM EXACTLY DEFINING THE CURRENT IMPULSES EMANATING FROM SAID PHOTOCELLS, A DISCRIMINATOR CONTROLLING THE COUNTING DIRECTION IN DERIVATION FROM THE PHASE OF THE EXACTLY DEFINED CURRENT IMPULSES, AND A MECHANISM FOR DIRECTIONALLY COUNTING THE IMPULSES FROM SAID DISCRIMINATOR.