Patent ID: 7791712

Claim:
A chromatic point sensor optical pen operable to provide a signal usable to measure a distance to a surface, the chromatic point sensor optical pen comprising: a housing; an optical element portion that provides longitudinal chromatic dispersion for radiation emitted from the chromatic point sensor optical pen, and that receives radiation reflected from the surface, the optical element portion defining an optical axis of the chromatic point sensor optical pen; and a fiber optic interface subassembly, comprising: a mounting element that is fixed relative to the housing, the mounting element including a hole configured to receive at least an optical fiber; and an aperture element that is fixed relative to the mounting element such that a surface of the aperture element is inclined at an angle T 1 relative to a plane that is normal to an axis of the hole, the aperture element providing an aperture fixed at an aperture operating position relative to the optical element portion and proximate to a center of an end of the hole, the aperture having an inner diameter D 2 , wherein the fiber optic interface subassembly is configured such that, in operation, at least an optical fiber is received and constrained in the hole with an axis of the optical fiber approximately coinciding with the axis of the hole, and with an end of the optical fiber positioned proximate to the aperture and aligned with the aperture such that the inner diameter D 2 of the aperture falls within a projection of an outer diameter D 1 ′ of the optical fiber along the direction of the fiber axis.