Electromagnetic field vector components precise measurements in accelerating structures

A precise measurement method for resonator electric or magnetic vector components values and their space positions, based on the application of a photosemiconductor plate, is presented. The optical system for the 433 MHz RFQ accelerating structure is realized by means of serial produced micro-alignment telescopes; the method allows one to discriminate the field axis fluctuations at the micron level and provides several percents and tenths of percents precision for accelerating efficiency and modulation period measurements respectively.