| 摘要 |
PURPOSE:To obtain a checker which indicates the working condition of an automatic correcting mechanism and to announce a measurable range to a measuring person by providing a small mark on an objective lens and further providing a use range mark on a focal plate. CONSTITUTION:A small mark 11 is provided at the center of an objective lens 1 to permit image-formation from infinity up to the mark 11 by moving a focusing lens 2 in an arrow direction. The range of an automatic correcting mechanism displays an automatic correcting range circle 9 on the cross lines 7 of a focal plate 5, and indicates that when the image of the mark 11 is formed on the plate 5 and if said image formation is within the range 9, the automatic correcting mechanism is working normally. The plate 5 is fitted in the frame 12 in a lens barrel 10, and is fixed to the barrel 10 by means of screws 13, 13, 13 screwed to said frame 12 from the top, bottom, right and left on the outside part of the barrel 10. The cross lines 7 and a stadia line 8 on the vertical line of the cross lines are provided to the plate 5. The circle 9 is so provided as to contain said line 8 therein. |
