• 3D-Backgroundstructure out of two detectionplanes the laser´s line is reflected from in a normal setup.

—-

Two exactly rightangled matt and light colored planes in vertical with two functions:

1. While calibration, the calibpointspattern has to be fixed these planes. The planes are defined as the XY-plane (where Z is equal zero) right and ZY-plane (where X is equal zero)left. (In practice the position of the XZ-plane, where Y is equal Zero, isn´t important: It is 20mm below the lowest row of calibpoints. The origin of the 3D coordinatesystem is right there (20mm below) and the planes meet)
2. While scanning, both planes have to reflect the laserline. Out of the angle, the lines hit each other, David calculates the position of the laserlight-plane and the 3D data of the reflected beam of the object.

—-

Tips:

• The calibpointspattern has to be fixed accurately. Both at the same heigth and exactly rightangled. Glue it laminar, not only tape it. Best is to use selfadhesive material for the printout.
• You can remove the pattern for scanning.

• The strength of the laserlight, reflected by the planes should be rather equal in amount to that reflected by the object (to ease the cam´s settings). So, if you want to scan darker objects, you have either to make your objects brighter (babypowder) or use darker material for the detectionplanes.

Note: There are some other ways to use DAVID-Laserscanner with different background- or even foregroundstructure. See: Windowsetup, negative Window