Relativity theory in an orthogonal reference system (Q2708807)

This paper is written in the same spirit as the book by \textit{D.-E. Liebscher} [``Relativitätstheorie mit Zirkel und Lineal'', Akademie Verlag Berlin (l. Aufl. 1977; Zbl 0381.51002, 2. Aufl. 1994; Zbl 0749.51021] to visualize the special relativistic relations between spatial and temporal coordinates. Inspite of the large number of different existing presentations, the author has found in his figure 2, as far as I know, a really new visualization, which, moreover, makes a careful distinction between orthogonality in the Euclidean and in the Lorentzian sense.