Abstract: A collimator filter (10) comprises an entry surface (11) to receive incident light (Li, Li?) at different angles of incidence (?i, ?i?) and an exit surface (12) to allow output light (Lo) to exit from the collimator filter (10). A filter structure between the entry surface (11) and the exit surface (12) transmits only parts of the incident light (Li) having angles of incidence (?i) below a threshold angle (?max). The filter structure comprises a patterned array of carbon nanotubes (1), wherein the nanotubes (1) are aligned extending in a principal transmission direction (Z) between the entry surface (11) and the exit surface (12). The nanotubes (1) are arranged to form a two dimensional pattern (P) transverse to the principal transmission direction (Z). Open areas of the pattern (P) without nanotubes (1) form micro-apertures (A) between the nanotubes (1) for transmitting the output light (Lo) through the filter structure.

Abstract: An organic electroluminescent device includes a substrate, a first electrode arranged on the substrate, and a functional organic layer arranged on the first electrode. The functional organic layer is adapted to emit electromagnetic radiation A second electrode is arranged on the functional organic layer. The functional organic layer includes a matrix material and an emitter material. The emitter material is neutral or ionically charged. The emitter material is selected from the group of ionic transition metal complex, neutral transition metal complex, polymer emitter and combinations thereof, wherein the matrix material comprises at least one ionic charge carrier transporting material, wherein the ionic charge carrier transporting material is selected from the group of electron-transporting material, hole-transporting material, ambipolar-transporting material and combinations thereof, and wherein the at least one ionic charge carrier transporting material is ionically charged.

Abstract: An organic electroluminescent device includes a substrate, a first electrode arranged on the substrate, and a functional organic layer arranged on the first electrode. The functional organic layer emits electromagnetic radiation. A second electrode is arranged on the functional organic layer. The functional organic layer includes at least one ionic component and one emitter material having a band gap. The emitter material is selected from the group of ionic transition metal complex, neutral transition metal complex, polymer emitter and combinations thereof. The organic electro-luminescent device is adapted to work in two modes, wherein a pre-biasing mode comprises applying a first voltage being a constant or pulsed value less than and/or equal to the band gap to the first and the second electrode.