Available laboratory UV spectroscopic data do not usually fulfill all the conditions which are required for reducing observational data of planetary atmospheres: absolute wavelength calibration, wide wavelength range including the mid-UV, spectral resolution, absolute determination of the absorption coefficients, data at various temperatures. Faced with this fact in our research program on the structure and composition of Titan atmosphere, we have developed a suitable laboratory facility. We describe this experimental facility: it gives absolute absorption coefficients at 0.1 ¿ resolution in the range 185--350 nm with sample temperatures adjustable between -50 ¿C and +50 ¿C. The future program to be implemented with this facility includes studies on nitriles and polyacetylenes. ¿ American Geophysical Union 1991