METHOD AND DEVICE FOR TRIANGULATION-BASED DISTANCE MEASUREMENT

Method for determining distances to an object to be measured based on the principle of triangulation and using a high dynamic range image sensor, in particular with a piecewise-linear multi-slope sensitivity characteristic, the method comprising generating and emitting a measuring light beam, directing the measuring light beam to the object to be measured, detecting a reflection of the measuring light from the object with respective pixels of the image sensor during a defined detection sequence (t 0 -t e ) and deriving distance information based on the detected reflection. The detection sequence (t 0 -t e ) comprises a number of at least two exposure sub-sequences each defining a particular exposure period and saturation limit for the pixels of the sensor, wherein the exposure periods and saturation limits are defined so that the final total charge for substantially every pixel is below the saturation limit of the last exposure sub-sequence. To this end, a successive exposure sub-sequence comprises a higher saturation limit than its prior exposure sub-sequence and each saturation limit defines a maximum charging level of the pixels for the respective exposure sub-sequence. The pixels are at least partly exposed by the reflected measuring light whereby the charge of each exposed pixel changes, and the charge of each pixel reaching at least one of the maximum charging levels during the detection sequence (t 0 -t e ) is limited to the respective saturation limit for the period of the corresponding exposure sub-sequence.