--- /dev/null
+.. _scaled_jacobian_page:
+
+***************
+Scaled Jacobian
+***************
+
+The **Scaled Jacobian** mesh quality criteria, is a scalar measure of the deviation from the perfect element in the geometrical sense, this measure normalize the range of reported values
+between [0,1] for a normal element, the value of 1 is considered a perfect element and 0 a element with a collapsed side. Negative values are also accepted for invalid elements.
+
+The **Scaled Jacobian** is implemented for volumetric elements returning 0 for polyhedrons. For tetrahedron and hexahedron the close form
+is defined in `[1] <https://gitlab.kitware.com/third-party/verdict/-/blob/master/SAND2007-2853p.pdf>`_, for pyramids the minimum scaled jacobian of the four tetrahedrons formed
+in the four vertices of the pyramid base is reported, for pentahedrons a decomposition into tetrahedron is also done and finally for hexahedron prisms the minimum scaled jacobian between two pentahedrons and one hexahedron is reported.
+
+* Geometrically the Scaled Jacobian of a **tetrahedron** can be understood by the follow figure:
+
+ .. image:: ../images/scaled_jacobian_tetra.png
+ :align: center
+
+ The reported Scaled Jacobian will be 1 if :math:`\alpha=45^{\circ}`
+
+* For **hexadrons** this measure return 1 for the perfect non rotated elements:
+
+ .. image:: ../images/scaled_jacobian_hexa.png
+ :align: center
+
+ The reported Scaled Jacobian will be 1 if :math:`\alpha=0^{\circ}` for all the vertices
+
+
+*To visualize the Scaled Jacobian quality criterion in your mesh:*
+
+.. |img| image:: ../images/scaled_jacobian.png
+
+#. Display your mesh in the viewer.
+#. Choose **Controls > Volume Controls > Scaled Jacobian** or click *"Scaled Jacobian"* button |img| of the toolbar.
+
+ Your mesh will be displayed in the viewer with its elements colored according to the applied mesh quality control criterion:
+
+ .. image:: ../images/scaled_jacobian_mesh_tetra.png
+ :align: center
+
+
+**See Also** a sample TUI Script of a :ref:`tui_scaled_jacobian` filter.
