Abstract: The invention relates to a method for fabrication of a balance spring of a predetermined stiffness comprising the steps of fabricating a balance spring in dimensions of increased thickness, determining the stiffness of the balance spring formed in step a) in order to remove, locally, a volume of material, in order to obtain the balance spring having the dimensions necessary for said predetermined stiffness.

Abstract: The invention relates to a method for fabrication of a balance spring of a predetermined stiffness comprising the steps of fabricating a balance spring in dimensions of increased thickness, determining the stiffness of the balance spring formed in step a) in order to remove a volume of material to obtain the balance spring having the dimensions necessary for said predetermined stiffness.

Abstract: The invention relates to a method for fabrication of a balance spring of a predetermined stiffness comprising the steps of fabricating a balance spring in dimensions to obtain a deliberately lower stiffness, determining the stiffness of the balance spring formed in step a) in order to compensate for said missing thickness of material required to obtain the balance spring having the dimensions necessary for said predetermined stiffness.

Abstract: In the present invention a new atomic clock is proposed comprising: at least one light source adapted to provide an optical beam, at least one photo detector and a vapor cell comprising a first optical window, said optical beam being directed through said vapor cell for providing an optical frequency reference signal, said photo detector being adapted to detect said optical frequency reference signal and to generate at least one reference signal, wherein—said atomic clock comprises a first optical waveguide arranged to said first optical window, said first optical waveguide being arranged to incouple at least a portion of said optical beam, said first optical waveguide being sized and shaped so that said first guided light beam is expanded,—a first outcoupler is arranged to outcouple at least a portion of said guided light beam to said vapor cell,—the thickness t of the atomic clock is smaller than 15 mm.

Abstract: The disclosure concerns an infrared emitter is provided comprising a metalized membrane emitting infrared light in operation. The membrane comprises a two dimensional array of infrared wavelength sized through-holes and to each side a thin metal layer comprising also an array of through-holes. The through-holes are arranged as a two-dimensional periodic array and each of said through-holes have a cross section having a maximum and a minimum dimension of less than any wavelength of the emitted infrared light. The peak wavelength of the emitted infrared light is proportional to the periodicity of the through-holes. At least one of the metal layers is connected to an electrical current source that provides an electrical current that heats at least one of the metal layers so that a narrow bandwidth and highly directive light beam of infrared light is emitted. The membrane is arranged on a membrane support and both are made of a material that resists to temperatures higher than 400°.

Abstract: An infrared transmitting cover sheet for receiving incident light having incident visible light and incident near infrared light. The infrared transmitting cover sheet includes: infrared transmission means arranged to transmit at least 65% of the incident near infrared light, through the infrared transmitting cover sheet, visible light transmission means arranged to transmit as less as possible incident visible light having wavelengths lower than 600 nm, excluding the wavelength of 700 nm, through the infrared transmitting cover sheet, and reflection means arranged to reflect a portion of the incident visible light to the side of the incident light.

Abstract: The present disclosure concerns a method for determining an instant velocity of a user using a sensing device destined to be worn on an arm of the user and comprising a motion sensor for measuring a motion signal; the method comprising: measuring the motion signal and identifying when the user is performing a rhythmical activity; identifying when the user is walking or running; providing a relationship between the measured motion signal and corresponding motion features relating to a propulsive impulsion of a user's step; estimating a frequency of the user's step and a user-relative step length of the user using the motion features; and determining a user-relative instants velocity by combining the estimated step frequency and the estimated step length; the instant velocity being determined from the user-relative instant velocity using a calibration factor from the user-relative instant velocity using a calibration factor.

Abstract: A tablet for pharmaceutical use has on at least one part of its surface a diffractive microstructure which generates diffraction effects which can be perceived in the visible spectral range and which serve as visual safety feature. The tablet includes a plurality of individual powder particles, where the diffractive microstructures are impressed into the surface of the individual powder particles. A compression tool to produce such tablets has on one pressing surface of the compression tool micro-structures, where the microstructures have dimensions which are smaller than the dimensions of the individual crystallites of the material of the pressing surface of the compression tool. The micro-structures of the compression tool can be produced for example by ion etching or by imprinting.

Abstract: A method for the wet-chemical etching of a highly doped silicon layer in an etching solution is provided. The method includes using, as an etching solution so as to perform etching homogeneously, an HF-containing etching solution containing at least one oxidizing agent selected from the group of peroxodisulfates, peroxomonosulfates, and hydrogen peroxide.

Abstract: A solar photovoltaic module (1) intended to receive incident light, said incident light comprising incident visible light and incident near infrared light, visible light being defined as light having a wavelength between 380 nm and 700 nm, excluding 700 nm and near infrared light is defined as light having a wavelength between 700 nm and 2000 nm, characterized in that said solar photovoltaic module (1) comprises: —a photovoltaic element (2), sensitive to near-infra red light, —at least a first infrared transmitting cover sheet (4), arranged to one side of said photovoltaic element (2), comprising: —infrared transmission means arranged to transmit at least 65% of said incident infrared light through said infrared transmitting cover sheet, —visible light transmission means arranged to transmit as less as possible incident light having wavelengths lower than 600 nm, preferably lower than 650 nm, more preferably lower than 700 nm, excluding the wavelength of 700 nm, through said infrared transmitting cover sheet

Abstract: The invention concerns a pressure transducer comprising a deflecting membrane, said membrane comprising two piezoresistors (10, 11) of different types, said piezoresistors being arranged such that a same stress or a same strain is applied on said piezoresistors and said piezoresistors (10, 11) yield changes in resistance, wherein a piezoresistor of a first type (10) is positioned such that its current direction is perpendicular to the stress direction (trans verse) and a piezoresistor of a second type is parallel to the stress direction (longitudinal), allowing, when a tensile stress is applied to the transducer, said piezoresistor of the first type to increase its resistance and said piezoresistor of the second type to decrease the resistance; or when a compressive stress is applied to the transducer, said piezoresistor of the first type to decrease its resistance and said piezoresistor of the second type to increase the resistance; wherein said piezoresistor of the first type (10) has a specific width and a

Abstract: The invention relates to a grating coupler comprising: —an optical substrate arranged to transfer a light beam, and —a diffraction grating arranged on, or imbedded in, the surface of said optical substrate, said diffraction grating comprising diffraction grating elements comprising each a coating arranged asymmetrically on said diffraction grating elements. The grating coupler is further arranged to satisfy the condition: (n1×sin(I?I)+?2)/?×P>1, wherein n1 is the refractive index of the optical medium to the incident light side of the diffraction grating elements, n2 is the refractive index of the optical medium to the diffracted light side of the diffraction grating elements, lal the absolute value of the incident angle of the light beam incident on the grating coupler ? is the vacuum wavelength of the diffracted light, and P is the period of the diffraction grating elements.

Abstract: A guided mode resonance device, comprising—a substrate,—a waveguide,—a grating structure associated with said waveguide, said grating structure being arranged to an incident surface of said substrate, said incident surface being intended to receive an incident light beam provided by at least one light source, said incident light beam having an incident angle, defined relative to the normal of said waveguide, said grating structure comprising at least one elementary structure comprising at least a first-type grating structure and at least a second-type grating structure,—wherein:—said waveguide is arranged to transfer light from_the first-type grating structures to the second-type grating structure and also to transfer light from the second-type grating structures to the first-type grating structure,—said first-type grating structure is arranged to couple out a first light beam,—said second-type grating structure is arranged to couple out a second light beam,—said first light beam having a different spectral d

Abstract: The disclosure concerns an infrared emitter is provided comprising a metalized membrane emitting infrared light in operation. The membrane comprises a two dimensional array of infrared wavelength sized through-holes and to each side a thin metal layer comprising also an array of through-holes. The through-holes are arranged as a two-dimensional periodic array and each of said through-holes have a cross section having a maximum and a minimum dimension of less than any wavelength of the emitted infrared light. The peak wavelength of the emitted infrared light is proportional to the periodicity of the through-holes. At least one of the metal layers is connected to an electrical current source that provides an electrical current that heats at least one of the metal layers so that a narrow bandwidth and highly directive light beam of infrared light is emitted. The membrane is arranged on a membrane support and both are made of a material that resists to temperatures higher than 400°.

Abstract: A shock-absorber and/or vibration-absorber device is proposed, comprising at least one flexible element able to deform under the effect of a stress; said device being remarkable in that it includes at least one so-called dissipative layer made from a material having a shear modulus lower than the shear modulus of the flexible element, a shock-absorbing factor greater than the shock-absorbing factor of said flexible element, and at least partially secured to said flexible element such that a flexion of the flexible element, under the effect of a stress, provides shearing of the dissipative layer making it possible to dissipate at least part of the energy from said stress. A method for manufacturing said shock-absorber device is also disclosed.

Abstract: The invention concerns a micro-machined vapor cell comprising a central silicon element forming a cavity containing vapor cell reactants such as alkali metal or alkali metal azide, buffer gas(es), and/or anti relaxation coating(s); a first and a second glass caps sealing the cavity; and a solenoid arranged to provide a homogeneous magnetic field to said vapor cell. The solenoid is coiled directly on the central silicon element of the vapor cell. This invention is an improvement for the highly miniaturized atomic clocks developments.

Abstract: The invention relates to a grating coupler comprising: —an optical substrate arranged to transfer a light beam, and—a diffraction grating arranged on, or imbedded in, the surface of said optical substrate, said diffraction grating comprising diffraction grating elements comprising each a coating arranged asymmetrically on said diffraction grating elements. The grating coupler is further arranged to satisfy the condition: (n1×sin(I?I)+?2)/?×P>1, wherein n1 is the refractive index of the optical medium to the incident light side of the diffraction grating elements, n2 is the refractive index of the optical medium to the diffracted light side of the diffraction grating elements, lal the absolute value of the incident angle of the light beam incident on the grating coupler ? is the vacuum wavelength of the diffracted light, and P is the period of the diffraction grating elements.

Abstract: A security device for the identification or authentication of valuable goods is described, including a thin material layer (22, 26) presenting a stochastic pattern including micro/submicrostructures, where the latter are arranged in blobs (2) each of which presents a complexity factor Cx = L 2 4 ? ? · A , where L is the perimeter of the blob and A its area, and wherein blobs having a Cx value greater than or equal to 2 cover at least 5%, preferably at least 15%, of the device surface. According to a preferred embodiment, the material layer may include a film including at least a first and a second polymers arranged respectively within a first and a second phases defining the micro/submicrostructures. Preferred processes of fabrication are also disclosed, as well as a method for securing a valuable good based on such a security device.

Abstract: A tamper seal includes an optical waveguide arranged to guide a propagating light-beam along a propagation direction. First and second portions of the tamper seal are configured to be arranged on first and second parts, respectively, of an object, said first and a second parts being movable relative to each other. The first portion comprises an input coupler arranged to couple incident light into said optical waveguide. The second portion includes at least one outcoupling surface arranged to couple out at least partially light guided in the optical waveguide. The input coupler, optical waveguide and outcoupling surface are arranged to transmit light from the input coupler to the outcoupling surface. The optical waveguide is further designed to be at least partially disruptable between the two portions, wherein the optical waveguide loses or at least partially changes its optical guiding properties after its disruption.

Abstract: The invention concerns a micro-machined vapor cell comprising a central silicon element forming a cavity containing vapor cell reactants such as alkali metal or alkali metal azide, buffer gas(es), and/or anti relaxation coating(s); a first and a second glass caps sealing the cavity; and a solenoid arranged to provide a homogeneous magnetic field to said vapor cell. The solenoid is coiled directly on the central silicon element of the vapor cell. This invention is an improvement for the highly miniaturized atomic clocks developments.