Optical power limiting device
AssigneeDornier GmbH
InventorsPeter Lautenschlager, Werner Scherber
Life of this patent
Estimating the term…
Abstract
An optical power limiting device whose transmissibility within a wave length range that is of interest is a function of the intensity of the incident radiation, the detuning of the resonance of surface plasmons being utilized. The device is particularly suitable for the protection of IR-detectors against the incidence of high radiation intensities.
Claims30
An optical power limiting device whose transmissibility within a predetermined wave length range is a function of intensity of incident radiation, comprising:
- a prism having at least one plane boundary surface;
- two layers, which are applied to the plane boundary surface, one above the other, a first of said two layers being an active layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range, and the second of said two layers being a dispersion layer comprising a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature;
- and
- means for guiding incident radiation into the prism and onto the plane boundary surface, whereby the dispersion layer is heated in response to increasing intensity of said incident radiation.
Method of protecting an IR detector from high intensity radiation, comprising the steps of:
- providing a prism having at least one plane boundary surface with two layers applied thereto, a first of said layers being an active layer made of a material having a dielectric function with a real component that is negative in a predetermined wave length range, and the second of said layers being a dispersion layer made of a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature;
- and
- heating said dispersion layer in response to increasing intensity of said radiation.
An optical power limiting device whose transmissibility within a predetermined wave length range is a function of intensity of incident radiation, comprising:
- a prism having at least one plane boundary surface;
- two layers applied to the plane boundary surface, one above the other, a first of said two layers being an active layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range, and the second of said two layers being a dispersion layer comprising a material having a refraction index in the predetermined wave length range that is strongly dependent on temperature;
- and
- means for heating said dispersion layer in response to the increasing intensity of said incident radiation.
An optical power limiting device comprising:
- a prism having at least one plane boundary surface;
- said first and second layers applied to the plane boundary surface, one above the other;
- first layer comprising a material having a dielectric function with a real component that is negative in the predetermined wave length range;
- said second layer having a variable refraction index;
- and
- means for varying said refraction index of said second layer in response to intensity of radiation transmitted to said prism.
Dependencies are inferred from the claim text.