Design of lens mounting for space application

Laser Focus system is an integral part of the Micromed Martian dust collector. Micromed helps to analyze the Martian atmosphere and records data regarding the same. An air flow, containing the dust particles is generated thanks to a mechanical pump connected to the instrument inlet. A sampling region is achieved at the exit of a converging pipe and through an optical system the particles are counted and classified in terms of size. This is achieved through the coherent beam from a laser that passes through a series of lenses to enter in an optical fiber which is then connected to the optical system generating a laser blade crossing the air flow. The laser light is reflected by the dust particles sucked in by the pump. This reflected beam enters a collector focusing it on a detector whose signal is collected for the further analysis that will allow dust characterization. The instrument development is coordinated by “Istituto Nazionale di Astrofisica” who is in charge also of the optical design which provides the design constraints to be followed while designing the opto-mechanical system. The working temperature of the system is in principle that of the martian atmosphere i.e. ranging from -100 °C to +30 °C and is critical for the optical system. The main challenges are to design compliant structures at the same time accommodating the thermal expansion of the optical elements and displacements due to temperature changes within the admissible limit.