An optical hinge and an optical hinge apparatus for providing an optical
link between a first circuit board and a second circuit board. The optical
hinge is made of two optical components, separated by an air gap, to allow
a light beam to transmit from one optical component to another via the air
gap. The optical components can be rotated relative to each other along a
rotation axis. Each of the optical components is optically coupled to an
opto-electronic device on a circuit board. Preferably, the light beam is
transmitted through the air gap along an optical path which is
substantially parallel to or coincident with the rotation axis. The light
beam can be used to carry optical signals in order to convey communication
data from one circuit board to another. The optical signals can be
transmitted in infrared frequencies or visible frequencies.