NOVELTY - An optoelectronic device comprises a stack structure including two electrodes and an optically active region placed between the electrodes and comprising at least optically active layer; and at least two fibers. The electrodes are located on the fibers, respectively. The active layer is located on any of the fibers. The fibers intersect and are in contact at the intersection so that the stack structure is formed at the intersection.    USE - For matrix displays, large advertising media, tent squares as solar-cell and light-emitting areas, embedded or encapsulated solar cells in roofing tiles, solar cells in glass windows, light-emitting clothes, or flexible document scanners.    ADVANTAGE - The invention is capable of light emission, light detection, and/or photovoltaic conversion. It can be manufactured reliably and cheaply. It can be structured in small pixels, thus reducing the probability for short circuits. No shadow masks or photolithography are involved in the device manufacture. Large-area mass production of solar cells, light-emitting structures, or photo detectors is possible with a small deposition area since only the fibers have to be coated. The fabric can be cut in application size after the production and can be contacted afterwards. It is flexible and mechanically stable and can be embedded in encapsulation material.    DETAILED DESCRIPTION - An optoelectronic device comprises a stack structure including two electrodes (21, 31) and an optically active region (4) placed between the electrodes and comprising at least optically active layer (41). It comprises at least two fibers (2, 3). The electrodes are located on the fibers, respectively. The active layer is located on any of the fibers. The fibers intersect and are in contact at the intersection (5) so that the stack structure is formed at the intersection. A first surface of the active region is in contact with the first electrode. A second surface of the active region is in contact with the second electrode.    INDEPENDENT CLAIMS are also included for:    (1) an array of optoelectronic pixels that are the inventive optoelectronic devices;    (2) a fiber coated with layer(s), comprising fiber substrate (30), an electrode, and an optically active region on top of the electrode and comprising an optically active layer;    (3) manufacturing a coated fiber comprising coating the fiber with optically active layer(s);    (4) manufacturing the inventive optoelectronic device comprising coating at least the second fiber with the active layer and arranging the fibers so that they intersect and are in contact at the intersection; and    (5) manufacturing an array of optoelectronic pixels.    The layer farthest from the fiber substrate is the active layer or one of the active layers.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic perspective view of a simple device.    Fibers (2, 3)    Active region (4)    Intersection (5)    Electrodes (21, 31)    Fiber substrate (30)    Active layer (41)