Optical apparatus and method therefor

摘要

A known configuration for detecting changes in wavelength of light from a laser device comprises a beam splitter for directing incident light thereupon towards a first photodiode via an optical filter and a second photodiode spaced relatively far apart from the first photodiode, thereby increasing an overall package size for the laser device in combination with a wavelength locker. The present invention overcomes this problem by disposing the first photodiode (114) adjacent the second photodiode (116) and employing an optical diffractive element (108) to direct, along distinct optical paths, light towards each of the first photodiode (114) and the second photodiode (116).