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 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 layer structure having at least two layers and also a sensor based on this layer structure are described. The layer structure comprises at least a substrate layer and at least one (light) waveguide layer and a coupling element for the coupling of the optical beam, the layer adjacent to the waveguide layer having a smaller refractive index than the waveguide layer, and at least one layer consisting of a photoaddressable polymer.

Abstract: The integrated-optical chemical and/or biochemical sensor comprises a resonant waveguide grating structure (1.1, 1.2, . . . ), e.g., a chirped grating. By illumination with incident light (21), a resonant electromagnetic field is excited in the grating structure (1.1, 1.2, . . . ). At least one parameter of the incident light, e.g., the angle of incidence (&thgr;1) or the wavelength (&lgr;1), is varied. Light (23) excident from the grating structure (1.1, 1.2, . . . ) is detected by detectors (4.1, 4.2, . . . ). Optionally, means for providing a feedback from the detectors (4.1, 4.2, . . . ) to the light sources may be provided, thus establishing a controlled closed-loop system. Hence independent simultaneous measurements in a multiple arrangement of such sensors (S1, S2, . . . ) is made possible. Moreover, a much higher density of sensors (S1, S2, . . . ) results.

Abstract: A biosensor comprises a waveguide into which light is coupled by a diffraction grating. The sample to be analyzed is placed on a reaction region in which a component of the immunological reaction is provided, for example antibodies or antigens. Fluorescence is excited on the surface of the waveguide because of the presence of a marker for example, a labelled antigen or antibody. Fluorescence is decoupled from the waveguide by the coupling diffraction grating or another diffraction grating. The waveguide is made of a material emitting light when it is excited by the marker excitation beam. This latter emission has a peak wavelength different from that of the emission radiation due to the marker used in the immunological reaction. Waveguide material fluorescence emission provides a reference during measurement.

Abstract: A light beam (6) is applied to a waveguide (3) in order to measure properties of the beam (6), e.g. the wavelength. According to the invention, the waveguide (3) has locally and/or time-varying resonances, e.g. by suitably designed grid couplers (4, 5). A light signal (7) is thus generated in the waveguide (3) as a direct measurement of the property to be measured and can be further processed by suitable means or evaluated. It is thus possible, for example, advantageously to produce a simple and inexpensive spectrometer.