Opto-mechanical Design Of The Sending/Receiving System In 3-Dimentional Measuring Laser Radar

This paper carried out a research on the measuring technique of 3D large-size profile system based on the Radar ranging principle of frequency-modulation phase measurement. A novel noncontact measuring method was proposed contraposing the 3D shape measuring requirement of a railway vehicle's front face. Opto-mechanical design process of the sending/receiving optical system was described and explained on which our research was focused.According to the designed common optical path structure of sending/receiving optical system, optical and mechanical structure design of the sending optical system, the receiving optical system and the common path system were studied respectively. Installation principle of the polarization beam splitter prism was illustrated in detail. An installation scheme of pressboard fixed prism using semi-kinematic principle was proposed and confirmed then.For the sending optical system, several focusing control mechanism was analyzed and compared. A design scheme of twin-cam reciprocating linear focusing structure was applied,realizing the motor's unidirectional rotation that would ensure the functions of guide pillar's smooth direction shift and focusing over-travel self-protection.In order for the multiple-lens in the sending/receiving system work normally in case of temperature change, its installation structure is designed to be athermal. By optimizing the structure, the rational design of spacing ring for use in space orientation was accomplished,which would be able to reduce the contact stress and to ensure the optical and mechanical system's axial consistency.