- - Spot lens (Microscopy) , a condensing lens in which the light is confined to an annular pencil by means of a small, round diaphragm (the spot ), and used in dark-field ilumination;
(the light; is confined; to an annular pencil; by means of a small, round diaphragm; L:a condensing lens)
the light
is confined
to an annular pencil by means of a small, round diaphragm L:a condensing lens