Beam forming optic aberrations' impact on maximum range of semiconductor laser based rangefinders

摘要

Miniature rangefinding modules based on pulsed semiconductor laser technology are becoming more and more popular components of a variety of modern optoelectronics devices where precise, fast and eye?safe range estimation is needed. Cur? rent trends associated with minimization of both physical dimensions and cost of such modules lead to the design approach relying on exact meeting the requirements of a given application, concerning the spatial resolution and especially the maxi? mum range. Optical components of a rangefinder cover a substantial part of its cost and determine its overall dimensions, but primarily – the indigenous parameters of the transmitter and receiver trains are crucial for the maximum measurable range. The quantitative analysis of transmitter optics aberrational characteristics impact on signal?to?noise ratio range de? pendence and thus the maximum range of a laser rangefinder is presented in the paper. Modern optical fabrication techno? logy offers a huge range of solutions, changing in imaging/projecting characteristics which implies the price level as well. Rangefinder optics has a very specific task which sometimes makes it unreasonable to fight for the diffraction limited perfor? mance. The article provides the approach how to determine the acceptable level of optical aberrations which still does not degrade the measurable range significantly.