The Center of the Laue Circle (CLC) indices (hkl) describes a small crystal tilt about a main direction specified by its [uvw] zone axis indices (Fig. 1). It is set once the zone axis has been chosen, changing the zone axis will reset the CLC to (000).

The crystal direction is specified by the zone axis (here Si [121] orientation) and the (hkl) CLC indices. Dragging the green cross moves the CLC on the Zeroth Order Laue Zone (ZOLZ). Note that the CLC indices are defined in the untilted ZOLZ plane ([uvw] × (hkl) = 0).

The arrows are used to move with high accuracy the CLC:

• Down.
• Up.
• Left.
• Right.
• Reset center.
• Find the [uvw] indices of closest zone axis.

The same arrows of the keyboard combined (depending on the operating system) with Shift, Shift + Ctrl, Shift + Alt, Ctrl + Alt or Shift + Ctrl + Alt also move the CLC at different speeds. To reset the center Shift + Ctrl + Alt + home center the CLC.

The Kikuchi threshold slider limits the number of plotted Kikuchi lines.