Technology of space angle measurement is widely used in aviation and national defence.Based on research of space angle measurement

this paper analyzes the measuring principle

optical system and electric circuits of experimental equipment

which uses position sensitive detectors(PSD) as the detector and laser diode(LD) as optical source.The result shows that experimental equipment is more precision and sensitive than old equipment.The relative error is only 0.0015% and the resolving power reach 2.4′ within the scope of ±1°.This test method can be applied to realize untouched measurement of large-scale gyroidal component in other similar situations.Some results concluded is useful for further research.