Abstract: The invention relates to a process for fabricating a semiconductor ridge pin junction (20, 21). According to the invention, judicious choices are made when defining hard masks and the sequence in which resist masks are formed for implantation (doping) and etching, which choices enable the conventional photolithography technique to be used despite the low precision of mask alignment (±100 nm) relative to underlying regions. By virtue of the process according to the invention, a ridge pin junction is formed, at lower cost and with shorter production times than in the prior art, with doped regions precisely spaced apart from the edge of the ridge.

Abstract: A PIN structure semiconductor optical receiver includes first and second electrical contact layers and an intrinsic layer disposed between them. The intrinsic layer includes a stud having a stud axis and a stud cross-section. The first and second contact layers have dimensions in a plane perpendicular to the stud axis that are greater than the stud's cross-section. These layers are also elongated and have longitudinal axes offset angularly relative to each other to minimize facing areas of said electrical contact layers.

Abstract: An apparatus and a method for multiplexing and demultiplexing Fiber Optic Interferometric Sensors (FOISs), including means for forming an optical source, at least one sensing cable, at least one wavelength demultiplexing system, and a calibration system.

Abstract: The invention deals with an apparatus and a method for multiplexing and demultiplexing Fiber Optic Interferometric Sensors (FOISs), said apparatus comprising: means (1) forming an optical source for providing l×n distinct trio (?qj, Fj, ?j) for the interferometric interrogation of l×n×m sensors, where for 1?j?p: ?qj is the frequency of the optical source 4qj (1?q?n/p), Fj is a RF frequency carrier generated upon the lights of the n/p emitters emitting at the frequency ?qj (1?q?n/p), and ?j is a time window where the light of the n/p emitters 4qj (1?q?n/p) are on, at least one sensing cable (100) comprising n groups of m fiber optic interferometric sensors each, and means for dedicating a unique given trio (?qj, Fj, ?j) to the interrogation of a unique group of m fiber optic interferometric sensors; at least one wavelength demultiplexing system (40) for separating the n frequencies ?qj (1?q?n/p and 1?j?p) into n/p outputs (33q for 1?q?n/p) containing respectively the lights of wavelength bands Bq for 1?q?n/

Abstract: The invention relates to a fiber-optic seismic sensor (200) with a test body (110), characterized in that the test body (110) comprises several separate dishes (113, 114, 115, 116) that are distributed around the direction of the sensitive axis of the sensor and two star-shaped elements (120, 130) placed on either side of the dishes (113, 114, 115, 116) and mechanically linking said dishes (113, 114, 115, 116) together.

Abstract: The invention relates to an apparatus for multiplexing Fiber Optic Interferometric Sensors (FOISs), which apparatus comprises means (1) forming the an optical source for providing m*n distinct wavelengths ?11, ?12, . . . , ?1n, ?21, ?22, . . . , ?2n, . . . , ?m1, ?m2, . . . , ?mn, the optical source including means for generating m groups (111, 112, . . . , 11m) of light pulses, each group 11j (1?j?m) being made up of n light pulses Pk(?j1), Pk(?j2), . . . , Pk(?jn) of distinct wavelengths ?j1, ?j2, . . . , ?jn, the n light pulses Pk(?j1), Pk(?j2), . . . , Pk(?jn) being time delayed one from another, Fiber Optic Interferometric Sensors distributed in m groups (51, 52, . . .

Abstract: The invention relates to an apparatus for multiplexing Fiber Optic Interferometric Sensors (FOISs), which apparatus comprises: means (1) forming the optical source for providing m*n distinct wavelengths ?11, ?12, . . . , ?1n, ?21, ?22, . . . , ?2n, . . . , ?m1, ?m2, . . . , ?mn, which means comprise other means for generating m groups (111, 112, . . . , 11m) of light pulses, each group 11j (1?j?m) being made up of n light pulses Pk(?j1), Pk(?j2), . . . , Pk(?jn) of distinct wavelengths ?j1, ?j2, . . . , ?jn, the n light pulses Pk(?j1), Pk(?j2), . . . , Pk(?jn) being time delayed one from another, Fiber Optic Interferometric Sensors distributed in m groups (51, 52, . . .

Abstract: The invention relates to a fiber-optic seismic sensor (200) with a test body (110), characterized in that the test body (110) comprises several separate dishes (113, 114, 115, 116) that are distributed around the direction of the sensitive axis of the sensor and two star-shaped elements (120, 130) placed on either side of the dishes (113, 114, 115, 116) and mechanically linking said dishes (113, 114, 115, 116) together.

Abstract: A device for comparing between N nominal wavelength values (&lgr;ei) and the wavelength values of optical signals coupled respectively with input ports (GEi) of a phasar with a grating (R) of guides (Gj), the said phasar comprising a main output port (GS (m) designed to collect the combination of the said signals, the said main output port (GS(m)) being placed at a focal point corresponding to a given interference order m of the grating, characterized in that the phasar comprises two secondary monitoring output ports (A, B) respectively placed in the vicinity of focal points corresponding to the interference orders m−1 and m+1 of the grating (R).

Abstract: The invention relates to a device for making a comparison between N nominal wavelength values (&lgr;ei) and the wavelength values of optical signals coupled respectively to input ports (GEl) of a phasar whose structure comprises a grating (R) of guides (Gj). According to the invention, the phasar comprises two monitoring output ports (A,B) respectively placed about focal points corresponding to two interference orders of the grating (R) designed to collect the combination of the said signals, and its structure is designed so that the transmission function approximates to a triangular shape in order to widen the monitoring span. The invention applies notably to the wavelength 15 monitoring of a tuneable optical source.

Abstract: The invention relates to a device for making a comparison between N nominal wavelength values (&lgr;ei) and the wavelength values of optical signals coupled respectively to input ports (GE1) of a phasar whose structure comprises a grating (R) of guides (Gj) According to the invention, the phasar comprises two monitoring output ports (A,B) respectively placed about focal points corresponding to two interference orders of the grating (R) designed to collect the combination of the said signals, and its structure is designed so that the transmission function approximates to a triangular shape in order to widen the monitoring span. The invention applies notably to the wavelength 15 monitoring of a tuneable optical source.

Abstract: A device for comparing between N nominal wavelength values (&lgr;ei) and the wavelength values of optical signals coupled respectively with input ports (GEi) of a phasar with a grating (R) of guides (Gj), the said phasar comprising a main output port (GS (m) designed to collect the combination of the said signals, the said main output port (GS(m)) being placed at a focal point corresponding to a given interference order m of the grating, characterized in that the phasar comprises two secondary monitoring output ports (A, B) respectively placed in the vicinity of focal points corresponding to the interference orders m−1 and m+1 of the grating (R).