An analyte detection apparatus comprises a radiation source (8, fig 2) for irradiating a sample such as the skin (11, fig 2); and a receiver 10, to receive an optical Raman spectrum of radiation transmitted back from the sample (11, fig 2) in response to the received radiation from the source (8, fig 2). The receiver 10 comprises a plurality of different types of analysis device 181-4 each arranged to receive a selected part of the received optical spectrum transmitted back from the sample (11, fig 2). There may be filtration elements 141-4 to split the energy in dependence on frequency or wavelength and direct selected parts of the spectrum 161-4 to the desired analysis device 18, such that more data may be derived from the most important parts of the spectrum. The analysis devices 18 may include CCD-based and CMOS-based spectrometers, and may have different levels of resolution or signal-to-noise ratio. The apparatus may be used to determine the concentration of an analyte in the blood such as glucose, lactate, fatty acids, urea, carbamide, cholesterol, alcohol or haemoglobin.