SELF-MIXING OPTICAL COHERENCE DETECTOR WITHOUT AN EXTERNAL BEAMSPLITTER

摘要

A detector (210, 310) that is configured to detect ghost-coherent reflections (260) produced by a superluminescent diode (SLD). The ghost reflections (260) are detected based on the optical coherence produced by reflections from surfaces (350, 450, 555) that are at integer multiples of the reflections within the SLD cavity (213), and thus exhibit the fine resolution discrimination that is typical of optical coherent detectors. In a preferred embodiment, the detector (210, 310) is configured to detect ghost reflections (260) from a surface at a particular multiple of the internal reflections. Ghost reflections (260) at other multiples are optically attenuated (330), or, if such reflections are known to be non- varying, canceled via a calibration procedure.