Verfahren zur Kohärenz-Biometrie und -Tomographie mit dynamischem kohärentem Fokus

• Main Author: FERCHER ADOLF FRIEDRICH DR
• Format: Patent
• Language: German
• Published: 31.08.2001
• Edition: 7
• Subjects: DIAGNOSIS; HUMAN NECESSITIES; HYGIENE; IDENTIFICATION; INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; MEDICAL OR VETERINARY SCIENCE; PHYSICS; SURGERY; TESTING

In the application of coherence distance measurement in medical biometry and in medical coherence tomography, an interferometric measurement light path is directed on the object to be measured and is focussed in order to improve the transverse resolution. Since the focus of the measurement light beam is fixed in the axial direction, high transverse resolution cannot be achieved over the entire object depth at all interferometric measurement points along the measurement light beam. This problem is not solved merely by displacing the focus along the measurement beam, since the focus will then lose coherence with respect to the reference light and the actual interferometric measurement location will then lie outside of this focus. In accordance with the invention, a simultaneous displacement of the reference light mirror be effected synchronously with the displacement of the focus by virtue of the optics generating the focus in order to maintain the coherence of the focus. The invention provides a method in which the focus is displaced and the coherence of the focus is maintained by one and the same moving optical element.