| 摘要 |
An interchangeable lens that can be fitted to and removed from a camera body, includes: an optical characteristic storage unit that stores information relating to optical characteristics of the interchangeable lens, including at least information related to vignetting of the interchangeable lens; and an optical characteristic transmission unit that transmits to the camera body the information relating to optical characteristics stored in the optical characteristic storage unit. And with an image height corresponding to one sixth of an image height from a center of an approximately rectangular photographic field to any of four corners of the photographic field being termed Y1, the optical characteristic storage unit stores, as the information related to vignetting of the interchangeable lens, information specifying vignetting at positions for which image heights from the center are integral multiples of Y1 from 2 through 6 inclusive. |
| 主权项 |
1. An interchangeable lens that can be fitted to and removed from a camera body, the interchangeable lens comprising:
an imaging optical system that includes a focusing lens; a lens position detection unit that detects a position of the focusing lens, and outputs a lens position signal; a lens position signal transmission unit that transmits the lens position signal outputted from the lens position detection unit to the camera body; an optical characteristic transmission unit that transmits to the camera body information relating to optical characteristics of the interchangeable lens, including at least information related to vignetting of the interchangeable lens; a transmission control unit that controls the lens position signal transmission unit and the optical characteristic transmission unit; a change detection unit that detects change of a signal level of a signal line for starting communication of the camera body; and a command data reception unit that receives predetermined data transmitted from the camera body and specifying various types of command, wherein with an image height corresponding to one sixth of an image height from a center of an approximately rectangular photographic field to any of four corners of the photographic field being termed Y1, the optical characteristic transmission unit transmits, as the at least information related to vignetting of the interchangeable lens, information specifying vignetting at positions for which image heights from the center are integral multiples of Y1 from 2 through 6 inclusive, the lens position signal transmission unit transmits the lens position signal outputted from the lens position detection unit to the camera body via a first transmission path, the optical characteristic transmission unit transmits the information relating to the optical characteristics to the camera body via a second transmission path that is different from the first transmission path, when the change of the signal level of the signal line for starting communication is detected by the change detection unit, the transmission control unit controls the lens position signal transmission unit so as to transmit the lens position signal outputted from the lens position detection unit to the camera body via the first transmission path, and upon receipt of predetermined data commanding transmission of the information specifying vignetting by the command data reception unit, the transmission control unit controls the optical characteristic transmission unit to transmit the information specifying vignetting to the camera body via the second transmission path. |
