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AssigneeAgilent Technologies, Inc.
InventorsRoberto Lano, Franco Delpiano, Cristiana Contardi
Estimating the term…
A device for monitoring the emission wavelength of a laser (10) includes a semiconductor slice or slab (14) having first (141) and second (142) opposed surfaces. The semiconductor slice (14) is exposed to the radiation at an angle such that a portion of said radiation impinges onto the first surface (141) at angles in the vicinity of the Brewster angle for the first surface (141). The radiation is thus refracted into the semiconductor slice (14) and caused to propagate towards the second surface (142) of the semiconductor slice (14). A wavelength selective filter (15) is arranged at said second surface (142) having associated a photodetector (11) to generate a signal (110) indicative of the wavelength of the radiation.
A device for monitoring the emission wavelength of a laser (10) emitting a lobe of radiation about a main emission axis, the device including a wavelength selective filter (15) exposed to said radiation to generate (11) an output signal (110) indicative of the wavelength of said radiation, characterised in that the device includes a semiconductor slice (14) having first (141) and second (142) opposed surfaces, said first surface (141) being adapted to be exposed to said radiation at an angle to said main emission axis such that a portion of said radiation impinges onto said first surface (141) at angles in the vicinity of the Brewster angle for said first surface (141) to be refracted into said semiconductor slice (14) towards said second surface (142), wherein said wavelength selective filter (15) is arranged at said second surface (142).
The device of any of the preceding claims, characterised in that said first surface (141) of the said semiconductor slice (14) is adapted to be exposed to the radiation of said laser (10) in the absence of any focusing means interposed in the propagation path of said radiation between said laser (10) and said first surface (141).
The device of any of the preceding claims, characterised in that the semiconductor of said slice (14) has a refractive index higher than 1.
The device of any of the preceding claims, characterised in that said semiconductor slice (14) is arranged with said first surface (141) in such a way that such radiation impinges onto said first surface (141) at angles between 50 and 75°.
The device of any of the preceding claims, characterised in that said radiation is propagated between said laser (10) and said first surface (141) in a medium having a refractive index in the vicinity of 1.
The device of any of the preceding claims, characterised in that said radiation is propagated between said laser (10) and said first surface (141) in air.
The device of any of the preceding claims, characterised in that said radiation in said lobe is polarised in a given direction and said first surface (141) of said semiconductor slice (14) extends in said given direction.
The device of any of the preceding claims, characterised in that it includes an optically sensitive element (12) adapted for generating a further signal indicative of the intensity of the radiation impinging thereon, said first surface (141) of said semiconductor slice (14) and said optically sensitive element (12) being adapted to be exposed to said radiation in angularly adjacent regions of said lobe, whereby the radiation of said lobe impinges partly onto said semiconductor slice (14) and partly onto said sensitive element (12).
The device of any of the preceding claims, characterised in that said wavelength selective filter (15) has associated therewith a respective optically sensitive element (11) adapted to generate said output signal indicative of the wavelength of said radiation.
The device of any of the preceding claims, in the form of an arrangement integrated with said laser (10) on a common platform (13).
Dependencies are inferred from the claim text.