a special flash tube that forms a ring around the front of the lens to provide more or less shadow-free lighting
Used with macro shots, it fits around the camera lens and provides a soft even illumination.
ring shaped electronic flash unit attached to the front of a lens. Used to give even frontal lighting in closeup situations.
A ring flash is a circular shaped electronic flash unit that is ideal for close-up photography. A ring flash fits around a lens and gives you shadowless, uniform frontal lighting.
Ring flashes are used in close-up photography. They usually consist of two parts. A shoe-mount unit is for mounting the flashes on a hot shoe, and a circular flash unit to be mounted in front of a lens.