An apparatus and method for monitoring the optical output of vertical cavity
surface
emitting lasers (VCSELS) utilizes a portion of light emitted by the VCSEL and scatters
and/or reflects this portion of emitted light so that it is directed towards a
detecting surface of a photodetector. In one embodiment, scattering elements may
be incorporated within the epoxy or other coupling medium used to couple the VCSEL
to the optical fiber. In another embodiment, the VCSEL may be coupled to an optical
fiber secured within a ferrule which has an end surface capable of reflecting or
scattering light and directing the light towards the photodetector. In another
embodiment, a reflective integrating member may be alternatively or additionally
used to reflect a portion of the emitted light to the photodetector. The photodetector,
in conjunction with electrical circuitry to which it is coupled, develops an electrical
signal which may be provided to laser control means to control and adjust the optical
output of the VCSELs.
