measurement in 3 Dimension

[Roland Melkert]

I'm not entirely sure what you mean, but here's my 2cts

First question is how translate length from Z axis to physical metric.

You will need a bounding box of the 3D data you want to measure.

Second question is when you have LDU how get width and height in physical metric.

Divide it by 2.5 (don't confuse this with mm2inch which divides again by a similar 2.54).