Demand is growing for affordable advanced sensor systems for use in counter-terrorism, criminal forensic analysis, and medical diagnosis. Next generation, million RPM class laser interferometry and spectrometry scanning systems are the ideal solution for this need due to their inherent ability to detect and identify microscopic quantities of evidence and resolve microscopic detail however a means to produce these systems with sufficient precision efficiently and inexpensively has been elusive. The scanning head is the heart of the system and in order for scanning heads of million RPM rotational speed class to be precisely aligned and balanced at operational speed they must be assembled while rotating. To facilitate this, a fully integrated feed-back based assembly system that measures and corrects optical alignment and balance of the scanning head during final assembly has been devised that subsequently enables economical high-precision, high production rate assembly.