| 摘要 |
PURPOSE:To use an extender variable magnification function for a photographic lens for a relay lens type color separation optical system, by incorporating a field lens into a photographic lens, and suitably setting the power of the field lens. CONSTITUTION:A photographic lens system 50 is constituted of a photographic lens 50 and a field lens 70, and an exit pupil position of the photographic lens 50 conforms with an entrance pupil position of a relay lens system 60 in a state that variable magnification by an extender is not executed, and is on the minus side. In this way, when power of the field lens 70 is decided in advance, even if variable magnification is executed by operating the extender, a variation of its pupil position is comparatively small, also vignetting of a luminous flux after the relay lens system 60 is a little, and a satisfactory image relay can be executed, irrespective of operation of the extender. |
