Use of the modified miniature-LDA in high spatial resolution application

Measuring the velocity structure of a boundary layer surrounding a cone, not only in subsonic, but also in transonic and supersonic is not yet possible. Therefore, the construction of a laser Doppler anemometer is demanded to realize these measurements. Based on the construction of the miniature-LDA, boundary layer measurements with very high spatial resolution of 25 /spl mu/m were possible. The opto-mechanical head of this BL-MLDA has a construction length of only 35 mm. The added electronics are battery-driven and consume under 1 W electrical power. The function of the system was shown by a first test; measuring a boundary layer of an air flow over a plate.