Zoom optical system for microscope

Claim 1

A PANCRATIC OPTICAL SYSTEM FOR A MICROSCOPE INCLUDING A ZOOM TYPE OF OBJECT FOR FORMING AN IMAGE HAVING A MAGNIFICATION RANGE OF AT LEAST 1:4, SAID OBJECTIVE COMPRISING A POSITIVE FRONT GROUP OF LENSES AND A REARWARD NEGATIVE CORRECTOR LENS ADJACENT THERETO, SAID GROUP BEING MOVED AS A UNIT SIMULTANEOUSLY WITH MOVEMENTS OF SAID NEGATIVE CORRECTOR LENS TO FORM A VIRTUAL IMAGE OF VARIABLE MAGNIFICATION, A STATIONARY POSITIVE RELAY LENS WHICH IS SPACED REARWARDLY OF SAID CORRECTOR LENS AND FORMS A REAL IMAGE OF CONSTANT MAGNIFICATION AT THE EYEPIECE FOCAL PLANE OF MICROSCOPE, SAID FRONT GROUP OF LENSES COMPRISING A POSITIVE MENISCUS SINGLET LENS WHICH IS DESIGNED I AND IS SPACED NEXT REARWARDLY OF THE MICROSCOPE COVER GLASS AT A VARIABLE DISTANCE S1, A FIRST DOUBLET LENS SPACED AT AN AXIAL DISTANCE S2 FROM LENS I AND BEING COMPRISED OF A FRONT DOUBLE CONCAVE LENS ELEMENT DESIGNED 11 WHICH LIES IN CONTACT WITH A REAR DOUBLE CONVEX ELEMENT DESIGNATED 111, A SECOND DOUBLET LENS SPACED AT AN AXIAL DISTANCE S3 REARWARDLY FROM LENS ELEMENT 111 AND COMPRISED OF A FRONT DOUBLE CONCAVE LENS ELEMENT DESIGNATED 1V WHICH LIES IN CONTACT WITH A REAR DOUBLE CONVEX LENS ELEMENT DESIGNATED V, A SINGLET POSITIVE LENS DESIGNATED V1 SPACED FROM LENS ELEMENT V AT AN AXIAL DISTANCE DESIGNATED S4, SAID NEGATIVE CORRECTOR LENS BEING A DOUBLET AND BEING SPACED REARWARDLY OF LENS V1 AT A VARIABLE AXIAL DISTANCE DESIGNATED S5, SAID DOUBLET BEING COMPRISED OF A FRONT DOUBLE CONCAVE LENS ELEMENT DESIGNATED V11 WHICH LIES IN CONTACT ON ITS REAR SURFACE WITH A CONVEX-CONCAVO LENS ELEMENT DESIGNATES V111, SAID RELAY LENS BEING SPACED AT A VARIABLE DISTANCE DESIGNATED S6 REARWARDLY OF SAID CORRECTOR LENS AND BEING COMPRISED OF A FRONT DOUBLE CONVEX LENS ELEMENT DESIGNATED 1X WHICH LIES IN CONTACT WITH A REAR CONCAVO-CONVEX ELEMENT DESIGNATED X, THE INDIVIDUAL EQUIVALENT FOCAL LENGHTS OF THE LENS ELEMENT 1 TO X BEING DESIGNATED RESPECTIVELY F1, -F2, F3, -F4, F5, F6, -F7 F8, F9 AND -F10 AND HAVING SPECIFIC VALUES SUBSTANTIALLY AS GIVEN IN THE TABLE HEREBELOW, THE MINUS (-) SIGN SIGNIFYING NEGATIVE FOCAL LENGTHS, THE AXIAL THICKNESS OF SAID LENS ELEMENTS BEING DESIGNATED RESPECTIVELY T1 TO T10 AND HAVING SPECIFIC VALUES SUBSTANTIALLY AS GIVEN IN THE TABLE HEREBELOW, THE SUCCESSIVE AIR SPACES BETWEEN SAID COVER GLASS AND SAID RELAY LENS BEING DESIGNATED RESPECTIVELY S1 TO S6 AND HAVING SPECIFIC VALUES SUBSTANTIALLY AS GIVEN IN THE TABLE HEREBELOW, THE VALUES FOR THE VARIABLE SPACES S1, S5 AND S6 BEING GIVEN FOR HIGH, LOW AND MEDIAN MAGNIFICATIONS OF SAID SYSTEM, SAID VALUES BEING GIVEN IN TERMS OF D WHICH REPRESENTS THE AXIAL LENGTH OF THE OBJECTIVE FROM THE SPECIMEN PLANE TO R16,