A light-emitting element driving circuit comprises a current supplier
serially connected to a light-emitting element and operative to supply a
current to the light-emitting element; and a switching unit operative to
control switching between the states of the current supplied to the
light-emitting element from the current supplier. The switching unit
includes a current path consisting of a diode and a semiconductor
switching element. The diode is connected in parallel with the
light-emitting element and in a forward direction directed from an anode
to a cathode of the light-emitting element. The semiconductor switching
element is connected serially to the diode and operative to switch
between the states of conductive and non-conductive based on a control
signal. A voltage drop across the current path when the semiconductor
switching element is made conductive is determined lower than a forward
voltage of the light-emitting element when it emits light.