A light-weight optical sensor has been developed for the simultaneous measurements of stratospheric trace gases. Its measuring principle is based on the detection of sunlight intensity with a miniature spectrometer. The wide spectral coverage of the miniature spectrometer offers the possibility for measurements of trace gases which absorb within the UV-VIS wavelength range, e.g. O3, NO2, and BrO. The new sonde can be operated at any place and is suitable for field-work due to the low weight of the payload (1.7 kg) and the autonomous portable telemetry system. In a first application ozone profiles were retrieved of the irradiance measurements with an adapted Dobson-spectrometer algorithm. The determined ozone profiles have been compared with profiles measured by electrochemical sondes and an ozone LIDAR.