| 摘要 |
The invention relates to the field of flow measurement engineering by means of laser Doppler anemometry. The application concerns a laser Doppler anemometer of miniature design based on laser diodes of tunable wavelength with wavelength stabilisation. Different optimised possibilities are described for using laser diode anemometers, and arrangements are explained for single- and multi-component anemometers, in particular for 3 orthogonal velocity components. A temperature-controlling element 12 of the laser diode 1 enables wavelength tuning and, in conjunction with a current-regulating device 13, stabilisation of wavelength and output. A current modulation device 14 and 14a can be used to produce frequency mixing of the Doppler frequency and the modulation frequency, so that it is possible to shift the Doppler frequency. The invention enables the construction of miniature laser Doppler anemometers of the very smallest dimensions and lightest design for all purposes of flow measurement engineering. <IMAGE> |
