Machine vision refers to applications in which the PC automatically makes a decision based on visual input from a camera. It is mainly used in industrial manufacturing in applications such as culling blemished oranges, drug capsule delivery etc. I.e a wide range od applications use it. production metrology applications especially in the electronics area have made use of this . serious measurement tools, color pictures , laser scanning, structured light, stereo viewing, and laser radar and all can fall into the category of application of this technology

2D vs. 3D Machine Vision
The 2D cameras see the length and width whereas the 3D ones see the length, width, and depth of the field. You can take two 2D cameras and mount 90 degrees apart from each other . This may work well for some applications but some parts' depths are hidden from the camera.

3D Machine Vision
In these systems, a specialized high speed camera is used and a projected laser line measure the physical deviations of the objects surface like the Volume, Flatness or shape, Density etc . The 3D vision systems have applications in areas such as the Volume, size and shape measurements of baked goods or produce, Completeness of molded parts, Flatness of stamped washers and much more.

for further details and application of this technology, visit this thread too;
http://studentbank.in/report-3d-machine-...ull-report