Surface checking device

Claim 1

MEASURING MEANS, COMPRISING CONTACTING MEANS FOR CONTACTING A SURFACE TO BE CHECKED AND HAVING AN APERTURE THEREIN DISPOSED IN THE PATH OF A BEAM OF LIGHT, MOVEMENT OF SAID CONTACTING MEANS WITH SAID APERTURE NORMAL TO SAID SURFACE BEING OF A DUNCTION OF THE VARIATIONS OF SAID SURFACE, OPTICAL MEANS FOR RECEIVING SAID LIGHT PASSING THROUGH SAID APERTURE AND TRANSMITTING SAID IMAGE THEREOF WHICH VARIES IN LOCATION NORMAL TO SAID SURFACE AS A FUNCTION OF THE VARIATION IN SAID SURFACE, POLARIZING MEANS HAVING TWO PORTIONS POLARIZED NORMAL TO ONE ANOTHER AND RECEIVING SAID IMAGE, ROTATABLE POLARIZING MEANS HAVING TWO PORTIONS POLARIZED NORMAL TO ONE ANOTHER AND THE REMAINDER BEING OPAQUE, SAID ROTATABLE POLARIZING MEANS BEING DISPOSED SEQUENTIALLY IN PARTIAL OPTICAL ALIGNMENT WITH SAID FIRST POLARIZING MEANS, WHEREBY SAID ROTATABLE POLARIZING MEANS ROTATES IN ORDER FOR IMAGE LIGHT TO PASS BOTH SAID FIRST AND SECOND POLARIZING MEANS WHICH REQUIRES SAID TWO POLARIZING MEANS PORTIONS WHICH ARE IN ALIGNMENT TO BE POLARIZED IN THE SAME DIRECTION, PHOTOELECTRIC MEANS DISPOSED IN ALIGNMENT WITH BOTH OF SAID FIRST AND SECOND POLARIZING MEANS FOR RECEIVING LIGHT PASSING THROUGH BOTH, LIGHT SEQUENTIALLY FALLING ON SAID PHOTOELECTRIC MEANS BEING LIGHT ALTERNATELY PASSING THROUGH THE TWO PORTIONS OF SAID FIRST POLARIZING MEANS, WHEREBY SINCE THE POSITION OF SAID APERTURE IMAGE IS A FUNCTION OF SAID SURFACE VARIATION THE DIFFERENCE IN INTENSITY OF LIGHT PASSING THROUGH THE DIFFERENTLY POLARIZED PORTIONS OF SAID FIRST POLARIZING MEANS AND FALLING ON SAID PHOTOELECTRIC MEANS IN A FUNCTION OF THE VARIATION IN SAID SURFACE.