Patent ID: 7575323

Claim:
A method for determining the distance from a measurement point on a tissue surface ( 10 , 13 ) of the eye ( 02 ), comprising: a) an initial light pulse ( 09 a ) is generated using a pulse light source ( 03 ) and is directed onto the measurement point of the eye, b) a reflector light pulse ( 11 ) reflected on the tissue surface ( 10 , 13 ) at the measurement point is intercepted by a light sensor ( 04 ), c) a followup light pulse ( 09 b ) of the pulsed light source ( 03 ) is triggered by the detection of the reflector light pulse ( 11 ) at the light sensor ( 04 ), d) the pulsed light source ( 03 ) generates further follow-up light pulses ( 09 b ) depending on the detection of the reflector light pulses ( 11 ) caused by the respectively preceding follow-up light pulses ( 09 b ) and thereby oscillates at a frequency F 1 , e) the frequency F 1 is measured directly or indirectly, f) the length X of the ray path starting from the pulsed light source ( 03 ) via the measurement point to the light sensor ( 04 ) is derived from the measured value F 1 and the specific speed of light c at which the light propagates in the medium along the ray path.