A method and sensor for detecting a chemical substance in an analyte. The diffuser includes a plenum section and a slitted section. The invention further relates to a method, a device and a software application product for retrieving reproduction vectors for vectors that have been N-level quantized, to a system for transferring representations of vectors, to a method, a device and a software application product for determining a joint codebook, and to such a joint codebook itself. In another embodiment, the AlSiN3:Eu2+ compounds further contains a halogen in an amount ranging from about zero to about 2 atomic percent, where the halogen may be fluorine, chlorine, or any combination thereof.