The ideality factor of LED chips in packaging is measured and studied based on the non-contact detection theory of LED.An experimental analysis has been implemented to evaluate varies of light-emitting diodes′ ideality factor.The measurement of LED spectrum under photoluminescence(PL) has been taken and the comparison between the ideality factors with or without packaging faults has also been investigated.It is found that the junction temperature and the injecting intensity of carrier are factor...