Abstract: The invention relates to a method for the separation of molecules having different excitation spectra, which form components of a gas. The molecules are excited by laser pulses in a way that the molecules to be separated are transferred into a state of excitation due to multi-absorption of energy quanta from laser pulses, and in which they are extracted from the gas so that they exist in a composition determined by the form of the laser pulses. According to the invention, the laser pulses are formed by an iterative process in which each laser pulse varies in its form depending on the extracted molecules' composition after their absorption of energy quanta.

Abstract: The invention relates to device serving as an orientation aid for blind and visually disabled, comprising at least one contactless distance measurement system (1,2) which provides correcting variables depending on the distance between the device and an object detected by the distance measurement system (1,2). At least one indicating device is also provided, which is impinged upon by the correcting variable of the distance measurement system (1,2) and which supplies an indication depending on the correcting variable. The indicating device comprises at least one tactile indicator (3) which is continuously or quasi-continuously displaced along a tactile path as monotone function of the distance measured by the distance measurement system (1,2). The tactile indicator can, for instance, comprise an adjustable element (3). The user can thus feel the distance measured by touching the position of the displaceable element (3).