| 摘要 |
PURPOSE:To reduce the man-hour for manufacturing focal plane shutter and also to facilitate a quality control by making the reflectance of the surfaces on a photographic lens side of split blades other than an aperture forming blade higher than the whole surface of the aperture forming blade. CONSTITUTION:Among plural split blades 11-15 constituting a front curtain 10, the whole surface of the split blade for forming the aperture is formed so as to have the same reflectance, and also, the surfaces on the photographic lens side of the split blades 12-15 other than the aperture forming blade 11 are formed to be the surfaces 12b-15b whose reflectance may become higher than that of the whole surface of the aperture forming blade 11. The surfaces on the photographic lens side of the split blades 12-15 other than the aperture forming blade 11 are formed to be the surfaces 12b-15b having the high reflectance, so that light from an object through a photographic lens is more reflected on a photodetecting element installed so as to measure the object light. And also, since it is allowed to form the whole surface of the aperture forming blade 11 so as to have the same low reflectance, material having the low reflectance itself is used, so that the shutter is easily manufactured. |
