| 摘要 |
A high performance zoom lens system (50) formed by multiple focus lens groups, multiple zoom lens groups and single auxiliary lens group (57) aligned on a common optical axis and arranged to collect radiation emanating from an object space and deliver that radiation to an axially stationary real image in an image space, such as on a film plane or video CCD. The multiple focus lens groups comprise a first focus lens group (52) of negative optical power that is axially movable and contains at least one non-spherical, non-plano, optically refractive surface, and a second focus lens group (53) of positive optical power that is axially movable. The multiple zoom lens groups comprise a first zoom lens group (55) of negative optical power that is axially movable, and a second zoom lens group (56) of positive optical power that is axially movable and contains an optical stop or iris. The single auxiliary lens group (57) is of relatively weak positive optical power compared to the other lens groups is axially stationary and contains at least one non-spherical, non-plano optically refractive surface. The remaining optically refractive surfaces of said zoom lens system (50) being substantially spherical or plano. By axial positioning of said multiple focus lens groups and said multiple zoom lens groups, the zoom lens system (50) provides a high level of optical performance at said real image through its entire and substantial focusing and zooming ranges. <IMAGE> |
