Abstract:
An integrated electronic circuit includes a cavity buried in a substrate. A surface of the substrate has a depression aligned above the buried cavity. The depression is filled with a material selected so that reflection of a lithography radiation on the substrate surface is attenuated. A resist layer is deposited on the circuit and then exposed to the radiation so that those resist portions which are located above the depression and those located away from the depression receive amounts of radiation that are below and above, respectively, the development threshold of the resist. An etching mask is therefore obtained on the circuit, which is aligned with respect to the cavity and its associated surface depression.
Abstract:
A microlaser having input and output mirrors defining a microlaser cavity, a solid active dielectric medium disposed in the microlaser cavity, and a pumping mechanism which pumps the microlaser and which includes at least one vertical cavity semiconductor laser. The microlaser may also include a microoptical focusing device, passive and/or active cavity switches. A plurality of such microlasers can be assembled to form a bidimensional network.
Abstract:
A first circuit element, which is reflective, is formed. A first layer, which is attenuating, is formed. above the first circuit element. A second layer, which is transparent, is formed above the first layer to fill an aperture in the first layer. An overlying lithography resist layer is then exposed to a radiation flux level below a development threshold but high enough that a sum of the radiation flux level and a reflected secondary radiation flux level exceeds the development threshold. The lithography resist layer is developed so as to obtain a mask having an opening through which the first and second layers are removed to form a second aperture which is filled to form a second circuit element.
Abstract:
A light concentration device includes: a plate including two principal faces and an edge between the two principal faces, a refractive index gradient existing between the two principal faces, and a diffraction grating functioning in reflection or semi-reflection that cooperates with one of the principal faces of the plate having the highest refractive index, the principal face having the lowest refractive index forming a front entry face for the light, at least one exit zone for the light being disposed on the edge.
Abstract:
The invention relates to an optical parametric oscillator characterized in that it comprises an OPO nonlinear material (18) and two mirrors (24, 26) on either side of said nonlinear material and forming an OPO cavity and a switched microlaser (2, 6, 8, 26) for generating an OPO cavity laser pumping beam.
Abstract:
The invention relates to a microlaser cavity having an active laser medium and reflection means at the entrance and exit of the cavity, characterized in that the reflection means are dimensioned in such a way that, in the active medium, the size of a pumping beam is at the most equal to the size of a laser beam emitted by the cavity.
Abstract:
An integrated electronic circuit includes a cavity buried in a substrate. A surface of the substrate has a depression aligned above the buried cavity. The depression is filled with a material selected so that reflection of a lithography radiation on the substrate surface is attenuated. A resist layer is deposited on the circuit and then exposed to the radiation so that those resist portions which are located above the depression and those located away from the depression receive amounts of radiation that are below and above, respectively, the development threshold of the resist. An etching mask is therefore obtained on the circuit, which is aligned with respect to the cavity and its associated surface depression.
Abstract:
The invention relates to a microlaser cavity (10) having: a solid active medium (2) emitting at least in a wavelength range between 1.5 and 1.6 &mgr;m, and a saturable absorber (4) of formula CaF2:Co2+ or MgF2:Co2+ or SrF2:Co2+ or BaF2:Co2+ or La0.9Mg0.5-xCoxAl11.433O19 or YalO3:Co2+ (or YAl5-2xCoxSixO3 YAl(1-2x)CoxSixO3) or Y3Al5-x-yGaxScyO12:Co2+ (or -3Al5-x-y2zGaxScyCozSizO12 Y3Al5-x-y-2zGaxScyCozSizO12) or Y3-xLuxAl5O12:Co2+ (or Y3-xLuxAl5-2yCoySiyO3) or Sr1-xMgxLayAl12-yO12:Co2+ (or Sr1-xMgx-yCoyLazAl12-zO12, with 0
Abstract:
The invention relates to a laser cavity having an active laser medium and two mirrors forming a Fabry-Perot cavity, characterized in that the cavity is at the optical stability limit and in that there are means for varying the optical length of the cavity, so as to pass from an optically unstable state into a stable state.
Abstract:
A light concentration device includes: a plate including two principal faces and an edge between the two principal faces, a refractive index gradient existing between the two principal faces, and a diffraction grating functioning in reflection or semi-reflection that cooperates with one of the principal faces of the plate having the highest refractive index, the principal face having the lowest refractive index forming a front entry face for the light, at least one exit zone for the light being disposed on the edge.