Method of and apparatus for determing height or profile of an object
OwnerMichiel Schallig, Willem Wijmainventors
Life of this patent
Estimating the term…
Abstract
The surface profile of, or distance to, an object can be accurately determined by scanning the surface (3) with an illumination beam (2) having a slit shaped cross-section and an intensity distribution in the slit width direction (= scan direction) and imaging the surface on an image sensor (5) comprising a number of pixels (51). By determining when a sensor pixel receives a maximum radiation intensity the position in the scan direction (x) of an illuminated surface area (31, 32) associated with said sensor pixel van be established and the height of this area can be measured by triangulation calculation.
Claims18
A method of determining at least local height of an object surface by scanning an illumination radiation beam and the object surface relative to each other in a scan direction and determining the intensity of radiation reflected by the object surface by means of an image sensor comprising a number of pixels, characterized by the combination of the steps of:
- scanning the surface by an illumination beam having an intensity distribution showing one main maximum;
- determining when a sensor pixel receives a maximum radiation intensity thereby establishing the position, in the scan directions, of an illuminated surface area associated with said sensor pixel, and
- measuring the distance, in a direction substantially to the scan direction, between said surface area and the image sensor.
Dependencies are inferred from the claim text.