<p>A conversion element (3) comprising a ceramic material (31) with a multiplicity of pores (32) provided for at least the partial absorption of at least one primary radiation (52) and for transforming the primary radiation (52) into at least one secondary radiation (53), wherein the conversion element (3) has a density greater than or equal to 97% of the theoretical solid-state density of the ceramic material (31), and the pores (32) in the conversion element (3) have a diameter substantially between 200 nm and 5000 nm.</p>