Optimizing 3-D sensors for precise measurements

JANUARY 19, 2009--Solid-state range imaging--an emerging technology capable of measuring the shapes, sizes, and locations of objects--has many potential applications in machine vision. Distance (or range) and brightness are measured simultaneously for every pixel, allowing 3-D image reconstruction.

Distance is determined by recording the light travel time to the object (also known as time of flight) using an amplitude-modulated light source and a specialized modulated image sensor. To achieve high measurement precision, the system must operate at high frequencies (tens of megahertz), thus placing high demands on the electronic design.

Moreover, because sensors do not necessarily respond linearly to electronic signals, the actual optical modulation response is not known a priori. Measuring the latter allows us sensor operation to be optimized and results in increased measurement precision. For more information, go to: http://spie.org/x31086.xml