Abstract: A ceramic conversion element having a multiplicity of columnar regions arranged within a ceramic or vitreous matrix, wherein the columnar regions have a preferential direction which makes an angle of at most 45° with a normal to the main surface of the conversion element, at least either the columnar regions or the matrix convert electromagnetic radiation of a first wavelength range into electromagnetic radiation of a second wavelength range different from the first wavelength range and, the columnar regions are formed by wavelength-converting monocrystalline or ceramic fibers and/or monocrystalline or ceramic platelets, said fibers and/or said platelets are provided with a reflective coating.