Apparatus and method for detecting light. The apparatus comprises means for splitting an input beam of light into at least a first beam of light and a second beam of light wherein the input beam of light is obtained from an optical coherence tomography arrangement. The apparatus also comprises means for modulating the first beam of light to provide a first modulated beam of light and means for modulating the second beam of light to provide a second modulated beam of light. The apparatus also comprises means for dispersing the first modulated beam of light to provide a first dispersed beam of light and means for dispersing the second modulated beam of light to provide a second dispersed beam of light. The apparatus also comprises means for detecting the first dispersed beam of light and means for detecting the second dispersed beam of light wherein the means for detecting the first dispersed beam of light and means for detecting the second dispersed beam of light are configured to convert the detected beams of light into electrical output signals.
