Abstract: A sensor (1) for detection of gas, in particular for detection of CO2. The sensor (1) has a contact face (2) which is directed towards a measuring site. The sensor (1) includes at least one radiation source (3), a measurement volume (4) for receiving the gas to be measured, and at least a first detector (5) for detection of radiation transmitted from the source (3) to the first detector (5) through the measurement volume (4). The sensor has a path (6) of the radiation between radiation source (3) and first detector (5). The radiation propagates along the path in a non-imaging way.

Abstract: A sensor (1) for detection of gas, in particular for detection of CO2. The sensor (1) has a contact face (2) which is directed towards a measuring site. The sensor (1) includes at least one radiation source (3), a measurement volume (4) for receiving the gas to be measured, and at least a first detector (5) for detection of radiation transmitted from the source (3) to the first detector (5) through the measurement volume (4). The sensor has a path (6) of the radiation between radiation source (3) and first detector (5). The radiation propagates along the path in a non-imaging way.

Abstract: A sensor (1) for detection of gas, in particular for detection of CO2. The sensor (1) has a contact face (2) which can be directed towards a measuring site. The sensor (1) includes at least one radiation source (3), a measurement volume (4) for receiving the gas to be measured, and at least a first detector (5) for detection of radiation transmitted from the source (3) to the first detector (5) through the measurement volume (4). The sensor has a path (6) of the radiation between radiation source (3) and first detector (5). The radiation propagates along the path in a non-imaging way.

Abstract: A sensor (1) for detection of gas, in particular for detection of CO2. The sensor (1) has a contact face (2) which can be directed towards a measuring site. The sensor (1) includes at least one radiation source (3), a measurement volume (4) for receiving the gas to be measured, and at least a first detector (5) for detection of radiation transmitted from the source (3) to the first detector (5) through the measurement volume (4). The sensor has a path (6) of the radiation between radiation source (3) and first detector (5). The radiation propagates along the path in a non-imaging way.

Abstract: A spectrometer includes: an entrance aperture, a collimator, intended to produce, from a light source, a collimated input light (5), a plurality of gratings arranged in a 2-D matrix, a plurality of detectors, and an exit aperture.

Abstract: A blazed grating is disclosed as well as mode hop-free tunable lasers and a process for fabricating gratings of this type. The grating lies in a general plane and includes a plurality of elongate beams carrying mutually parallel respective reflection surfaces spaced apart from one another with a predefined pitch, each of these reflection surfaces having a normal direction inclined at a grating angle ? to the normal direction of the general plane. The grating includes a plurality of resilient suspension arms connected to the beams and intended to be fastened to a grating support. A first pair of comb electrodes is provided for applying a mechanical force to this assembly, being placed on a first side of the grating, along an axis transverse to the beams, and designed so as to allow the pitch of the grating to be modified in response to the application of the mechanical force.

Abstract: A spectrometer includes: an entrance aperture, a collimator, intended to produce, from a light source, a collimated input light (5), a plurality of gratings arranged in a 2-D matrix, a plurality of detectors, and an exit aperture.

Abstract: A mode hop-free tunable laser including a gain medium, a microfabricated blazed grating, defining an external cavity of a given length, the blazed grating lying in a general plane and including a plurality of elongate beams carrying mutually parallel respective reflection surfaces spaced apart from one another with a predefined pitch, and actuating elements designed so as to allow displacements of the assembly with respect to a grating support within a plane substantially parallel to the grating general plane, and including actuation elements designed so as to apply a stretching and a displacement of the assembly in a direction transverse to said reflection surfaces, the blazed grating being arranged relative to an incident light beam provided by the gain medium so that the incident light beam impinges on the reflection surfaces with a substantially normal incident angle.

Abstract: A blazed grating is disclosed as well as mode hop-free tunable lasers and a process for fabricating gratings of this type. The grating lies in a general plane and includes a plurality of elongate beams carrying mutually parallel respective reflection surfaces spaced apart from one another with a predefined pitch, each of these reflection surfaces having a normal direction inclined at a grating angle ? to the normal direction of the general plane. The grating includes a plurality of resilient suspension arms connected to the beams and intended to be fastened to a grating support. A first pair of comb electrodes is provided for applying a mechanical force to this assembly, being placed on a first side of the grating, along an axis transverse to the beams, and designed so as to allow the pitch of the grating to be modified in response to the application of the mechanical force.

Abstract: An optical device, i.e., a wavelength selective filter, includes a grating having a finite length and is capable of filtering a given first wavelength within an operating wavelength region, said grating including a plurality of consecutive sections, each section including two sub-sections: a first sub-section having a first period ? and a second sub-section having a second period ?1, wherein said first period (?) satisfies the Bragg condition for said given first wavelength and the second period (?1) satisfies the Bragg condition for a second wavelength lying outside the operating wavelength region so as to form a grating with modulated coupling coefficient, wherein the succession of lengths of each section is non periodic. Preferably, the first (?) and second period (?1) are such that n?=m?1, wherein n and m are integers and satisfy one of the following conditions: if ?1>?, n/m is not an integer and if ?1<?, m/n is not an integer.

Abstract: A mode hop-free tunable laser including a gain medium, a microfabricated blazed grating, defining an external cavity of a given length, the blazed grating lying in a general plane and including a plurality of elongate beams carrying mutually parallel respective reflection surfaces spaced apart from one another with a predefined pitch, and actuating elements designed so as to allow displacements of the assembly with respect to a grating support within a plane substantially parallel to the grating general plane, and including actuation elements designed so as to apply a stretching and a displacement of the assembly in a direction transverse to said reflection surfaces, the blazed grating being arranged relative to an incident light beam provided by the gain medium so that the incident light beam impinges on the reflection surfaces with a substantially normal incident angle.

Abstract: A device for crossing optical beams. At least a first input optical waveguide is directed along a first axis, a second optical waveguide is directed along a second axis inclined with respect to the first axis, and a photonic crystal having a regular periodicity in an optical crossing region at the intersection of said first and second axis has, opposite the first and second input waveguides, a first and a second output waveguide to provide for exit beams.

Abstract: A wavelength selective grating-based filter includes a planar waveguide which includes a core surrounded by a cladding, the cladding including a lower cladding, the core being placed above the lower cladding, a lateral cladding adjacent to a first and a second opposite lateral sides of the core, and an upper cladding, said upper cladding being positioned above said core and lateral cladding. The waveguide also includes a grating structure, including a first and a second plurality of grating trenches formed in the lateral cladding in proximity of the first and second opposite lateral sides of the core, respectively. The first and second plurality of grating trenches are covered by the upper cladding.

Abstract: A method for guiding electromagnetic radiation by providing a photonic crystal made of a bulk material with a predetermined refractive index and having a periodic array of holes with predetermined radius, and feeding to that region an electromagnetic radiation having a wavelength in the fundamental photonic band and so related to the refractive index of the bulk material, to the radius of the holes and to the period of the array that, starting from an isotropic distribution of the wave vectors within a first angular range that is twice the angular extension of the first irreducible Brillouin zone of the photonic crystal, the corresponding group velocity vectors are rearranged as concerns direction and module so that at least 50% of them become directed within a second angular range that is about one-third of the first angular range and the width at half-maximum of the distribution of the modules of the vectors is lower than about two-thirds of the second angular range.

Abstract: A device for varying the direction of an optical beam. A first waveguide is directed along a first direction, a second waveguide is directed along a second direction different from the first direction, and a bending region is interposed between the first and the second waveguide. The bending region has a photonic crystal having a regular periodicity and at least a first and a second crystal axes substantially aligned with the first and second directions, and a reflecting surface delimiting the photonic crystal and so positioned and oriented as to reflect an optical beam coming from the first waveguide toward the second waveguide.

Abstract: An optical wavelenth selective filter on an optical waveguide and a method of making the same is provided. The filter is able to transmit a first predetermined band of wavelengths and to reflect a second predetermined band. The filter further includes a plurality of transmissive couples and reflective couples in series, with each of the couples including a first zone of high refractive index and a second zone of low refractive index adjacent to each other so as to form a structure with a high gap modulated refractive index.

Abstract: An integrated optical device having a first and a second integrated waveguide arranged so as to be in optical coupling relationship in a first and a second spaced-apart coupling region and having respective optically uncoupled waveguide sections in between the first and second coupling regions. A first and a second modulated refractive index structures are provided, each one formed along a respective uncoupled waveguide section; the modulated refractive index structures each having at least one pair of regions of mutually different refractive index adjacent to each other along the respective uncoupled waveguide section. The regions of mutually different refractive index have a portion of the respective uncoupled waveguide section and a gap formed in the uncoupled waveguide section, the refractive indexes of the regions differing from each other by at least approximately 1.5%.

Abstract: A device for crossing optical beams. At least a first input optical waveguide is directed along a first axis, a second optical waveguide is directed along a second axis inclined with respect to the first axis, and a photonic crystal having a regular periodicity in an optical crossing region at the intersection of said first and second axis has, opposite the first and second input waveguides, a first and a second output waveguide to provide for exit beams.

Abstract: A device for varying the direction of an optical beam. A first waveguide is directed along a first direction, a second waveguide is directed along a second direction different from the first direction, and a bending region is interposed between the first and the second waveguide.

Abstract: A method for guiding electromagnetic radiation by providing a photonic crystal made of a bulk material with a predetermined refractive index and having a periodic array of holes with predetermined radius, and feeding to that region an electromagnetic radiation having a wavelength in the fundamental photonic band and so related to the refractive index of the bulk material, to the radius of the holes and to the period of the array that, starting from an isotropic distribution of the wave vectors within a first angular range that is twice the angular extension of the first irreducible Brillouin zone of the photonic crystal, the corresponding group velocity vectors are rearranged as concerns direction and module so that at least 50% of them become directed within a second angular range that is about one-third of the first angular range and the width at half-maximum of the distribution of the modules of the vectors is lower than about two-thirds of the second angular range.