Specifications

1. Introduction
Semiconductor laser diodes arecompact, efficient and low-cost, but
usuallyhavepoorwavelengthcontrol,linewidthandstability. The
addition of an external frequency-selective cavity allows control
oftheoperatingwavelengthoverafewnmrange,withsub-MHz
linewidthandstability.TheMOGLabsCEL(seeFig.1.1)ismachined
fromasolidaluminiumblock, so that thelaserisstable, robust,
and insensitive to acousticdisturbances.The cavity is hermetically
sealed foradditional suppression ofenvironmentalfluctuationsand
drift.
The MOGLabs CELis a“cat-eye” design(seeFig. 1.2), inwhich an
external cavityisformedbetweentherearreflectingsurfaceofthe
semiconductor diode,and a cat-eye reflectorat several centimetres
fromthediode[1–3]. Ratherthanthecustomarydiffractiongrating
ofLittrow-configurationECDLs,ahighefficiencyultranarrowfilter
Figure 1.1: Inside the MOGLabs CELcateye laser.
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