| 摘要 |
PROBLEM TO BE SOLVED: To provide a light-wave range finder capable of preventing damage to a density filter and capable of surely fixing a setting position of the density filter whose density has been set.SOLUTION: A light-wave range finder measures a distance to a prism 280 by comparing reflected light from a measured object that is obtained by irradiating the prism 280 being the measured object with measurement light obtained from a light source 230 with internal reference light that is obtained from the light source 230 and whose light volume is adjusted by a density filter 310 in which transmitted light volume is variable. The density filter 310 comprises: a discoid density gradient film 311 having a density gradient in a circumferential direction; and a discoid protection film 312 disposed overlapping with the density gradient film 311 and having at least one uniform density. The density filter 310 is mounted on a density filter mounting part 131 with a fixing screw 313. |
