On October 31, 2016 Jeff Hulett presented the topic, “Optimizing Continuous Pulse LED Measurements for Maximum Accuracy” at the CIE-USNC meeting that was held in conjunction with IESNA.
This presentation not only highlighted the benefits of using continuous pulse method for measuring high power LEDs, but also introduced how to identify, quantify, and minimize errors when using continuous pulse method.
This paper generated some lively debate. Many attendees were surprised to see the large error values associated with pulse characteristics such as rise time and pulse width jitter, and they initially questioned the data. The discussions continued well into the lunch break.
After lunch Yuqin Zong of NIST presented a related paper on NIST’s new high power LED calibration service. Zong presented data showing LED calibrations he had performed using LM-85’s continuous pulse and single pulse methods. The data he presented corroborated Hulett’s claims as he found unexpectedly high errors with some continuous pulse measurements.