| 摘要 |
<p>A COMPACT ZOOM LENS SYSTEM HAVING A ZOOM RATIO OF AN APPROXIMATELY 3.5 TIMES COMPRISING A FIRST LENS GROUP (Ι) HAVING A POSITIVE REFRACTIVE POWDER, A SECOND LENS GROUP (ΙΙ) HAVING A POSITIVE REFRACTIVE POWER AND SPACED FROM SAID FIRST LENS GROUP (Ι) AT A FIRST DISTANCE, AND A THIRD LENS GROUP (ΙΙΙ) HAVING A NEGATIVE REFRACTIVE POWER AND SPACED FROM THE SECOND LENS GROUP (ΙΙ) AT A SECOND DISTANCE, SAID FIRST AND SECOND DISTANCES BEING VARIABLE DURING ZOOMING, WHEREIN 3.0 <FT/FW, AND LT/FT < 1.0 WHERE FT IS THE FOCAL LENGTH OF THE ZOOM LENS SYSTEM AT A TELEPHOTO POSITIONS, FW IS THE FOCAL LENGTH OF THE ZOOM LENS SYSTEM AT A WIDE ANGLE POSITION, AND LT IS THE DISTANCE FROM THE FIRST SURFACE OF THE ZOOM LENS SYSTEM ADJACENT THE OBJECT TO THE IMAGE PLANE OPPOSITE THE OJECT AT A TELEPHOTO POSITION.MOST ILLUSTRATIVE DRAWING: (FIGURES 1A,1B & 1C)</p> |
