| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a confocal measuring device that uses a confocal optical system to measure displacement of a measurement object and reduces a variation of accuracy in measuring the displacement of the measurement object with a variation of the wavelength of light. <P>SOLUTION: A confocal measuring device in the invention uses a confocal optical system to measure displacement of a measurement object. The confocal measuring device 100 comprises: a white LED 21; a diffraction lens 1 that causes light emitted from the white LED 21 to generate a chromatic aberration along an optical axis direction; an objective lens 2 that is arranged toward the measurement object 200 from the diffraction lens 1 and focuses the light, which generates the chromatic aberration at the diffraction lens 1, on the measurement object 200; a pinhole that transmits light to be focused on the measurement object 200, among the light focused by the objective lens 2; and a wavelength measuring part that measures a wavelength of the light passing through the pinhole. The focal length of the diffraction lens 1 is longer than a difference between the length from the diffraction lens 1 to the objective lens 2 and the focal length of the objective lens 2. <P>COPYRIGHT: (C)2013,JPO&INPIT |
