| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical barrel convenient for a user to adjust and correct twisting force at the time of assembly.SOLUTION: An optical barrel includes a cylindrical wall, a male screw, and a plurality of projections, and the cylindrical wall extends in a shaft direction. The male screw is formed in the cylindrical wall, and includes male screw ridges and male screw valleys extending spirally with a plurality of turns along the shaft direction, a clearance external diameter determined by the male screw ridges, and a clearance internal diameter determined by the male screw valleys. The plurality of projections protrude, are arranged at intervals at the male screw valleys, and have end faces positioned between the male screw valleys and the male screw ridges each apart from the male screw valleys. When the optical barrel is subjected to processing molding by using a metal mold, the plurality of projections perform correction to corresponding outer diameter dimensions of the metal mold, and thus can change twisting force of assembly with a female screw. |
