Abstract: A multiplicity of components form a photodiode array on a substrate. Each of the components consists of a transistor of the p-n-p type with the outermost p-doped layer being transformed into an optical filter by control of the anodic etching operation utilizing transistor characteristics of the respective transistor. The result can provide red, blue and green filters in a color camera.

Abstract: An interference filter having a layer with an area consisting of a porous material extending from the surface of the layer to the interior, the dimensions of the porous layer area in a direction normal to the layer surface have different values to provide for varying reflection or, respectively, transmission characteristics.

Abstract: In an interference filter having a layer with an area consisting of a porous material extending from the surface of the layer to the interior, the dimensions of the porous layer area in a direction normal to the layer surface have different values to provide for varying reflection or, respectively, transmission characteristics.

Abstract: A porous layer produced from silicon, germanium or aluminum by applying a wedge-shaped mask to the surface of the layer and by controlled elecrochemical etching along the mask.

Abstract: A multiplicity of components form a photodiode array on a substrate. Each of the components consists of a transistor of the p-n-p type with the outermost p-doped layer being transformed into an optical filter by control of the anodic etching operation utilizing transistor characteristics of the respective transistor. The result can provide red, blue and green filters in a color camera.

Abstract: In an analytic process using porous silicon, a substance is detected or its concentration in a fluid is determined based on the change in the optical property of porous silicon as a function of the refractive index of the substance present in the pores of the porous silicon, or of the fluid containing the substance. An analytic device for detecting a substance or for determining the concentration of a substance in a fluid with the use of porous silicon comprises a component at least partly consisting of porous silicon, the optical property of which is dependent upon the refractive index of the substance or of the fluid containing the substance, whereby a change in the optical property of the porous silicon is measurable to indicate detection of the substance or to determine the concentration of such substance in the pores of the porous silicon.

Abstract: A process for producing a structured area of porous silicon on a substrate, in which silicon is etched and structured by means of illumination, includes selectively aiming the illumination during or after the formation of the porous silicon directly at a selected area of a p-doped substrate in order to effect etching and structuring of the porous silicon in another area. A device for carrying out the process includes an illuminating system for supporting the etching process and for structuring the porous silicon, in which the illuminating system is selectively aimed during or after the formation of the porous silicon directly at a selected area of p-doped substrate in order to effect etching and structuring of the porous silicon in another area.

Abstract: The invention relates to an optical component consisting of transparent thin layers of differing thickness and refractive indices. Such optical components are used, for example, as interference filters and mirrors. Optical components made of layers with gradually changing refractive indices are also known as waveguides of anti-reflective coatings. The invention achieves the aim of using, instead of layers of ordinary materials, another material by means of a component in which the layers consist of porous silicon. The special advantages of porous silicon as a coating material arises not only from the ease and economy of manufacture, but also in the facility for obtaining gradual refractive index transitions. It is therefore very easily possible to make waveguides on a silicon chip.