  LHAASO project is to be built in south-west China, which use an array of 5137
election detectors for the measurement of the incident electrons arriving at
the detector plane. For the quality control of the big quantity of electron
detectors, a cosmic ray hodoscope with two-dimensional spacial sensitivity and
good time resolution has been developed. The first prototype of electron
detector is tested with the hodoscope and the performance of the detector is
validated to be consistent with the design.
