摘要 |
A chromatic confocal point sensor optical pen comprises a multi-stage optical configuration providing an enhanced range-to-resolution ratio. The optical configuration comprises at least first and last axially dispersive focusing elements that combine to contribute to the overall axial chromatic dispersion of the optical pen. The first focusing element receives source radiation and focuses that radiation at a first focal region internal to the multi-stage optical configuration and the last focusing element receives radiation from a last focal region internal to the multi-stage optical configuration and outputs the measurement beam. Intermediate focusing elements may provide additional focal regions internal to the multi-stage optical configuration. This configuration provides an unprecedented combination of extended sensing range, compact lens diameter, and high numerical aperture. The focusing elements may comprise refractive lenses or diffractive optical elements. |