What type of microscope uses a cone of light so that light only hits the specimen indirectly, producing a darker image on a brighter background? In a(n) _______ microscope, a probe located just above ...What type of microscope uses a cone of light so that light only hits the specimen indirectly, producing a darker image on a brighter background? In a(n) _______ microscope, a probe located just above the specimen moves up and down in response to forces between the atoms and the tip of the probe. When focusing a light microscope, why is it best to adjust the focus using the coarse focusing knob before using the fine focusing knob?