| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a distance measuring method and apparatus in which the time required for adjusting a focusing position is shortened by using low-precision range finding and high-precision range finding, and a shape measuring apparatus with the same packaged therein. <P>SOLUTION: A distance measuring apparatus comprises a high-precision range finding system, a low-precision range finding system and inter-lens distance change means. In the high-precision range finding system, light from a first light source is separated into first reference light which does not irradiate a subject and first measuring light which irradiates the subject through a focus unit including a plurality of lenses, and a distance to the subject is measured from a phase difference between the first reference light and the first measuring light. In the low-precision range finding system, light from a second light source the frequency of which is lower than that of the first light source is separated into second reference light which does not irradiate the subject and second measuring light which irradiates the subject, and the distance to the subject is measured from a phase difference or an arrival time difference between the second reference light and the second measuring light. The inter-lens distance change means changes an inter-lens distance between the plurality of lenses in the laser focus unit from a result of the low-precision range finding system. <P>COPYRIGHT: (C)2013,JPO&INPIT |
