The Lindsay microscope focus mechanism consists of a lever mounted to a pivot (A). Moving the lever (top arrow) slides the sample stage forward and backward. Note the position of the sample stage (green line) as the handle is moved from OUT position (L) to IN (R)>
These side images correspond to the top images. Left shows the position of the sample stage (A) when the focus lever is fully extended. Right shows the stage closer to the objective when the lever is pressed toward the back. Note the position markings on the side (below).
Focus position markings. Left shows a close focus position, Right shows a focus position far from the objective.