focusing drive, focusing knob
device for focusing the image in the telescope, by means of which the focusing lens can be moved in order to shift the image generated by the objective lens into the plane of the reticule, seade kujutise fokuseerimiseks pikksilmas, mille abil saab teravustamisobjektiivi liigutada, et nihutada objektiivi tekitatud kujutis niitristiku tasapinnale
