Method and System for Intrinsic LED Heating for Measurement

摘要

The present disclosure provides methods and apparatus for testing light-emitting diodes (LEDs), for example, measuring the optical radiation of an LED. In a method, a pulse-width modulated signal is provided to the LED. One or more characteristics of the PWM signal are varied so as to provide a forward voltage, Vf, corresponding to a target junction temperature, Tj, of the LED. The optical radiation of the LED is measured when the LED obtains the target junction temperature.

主权项

1. A method for measuring optical radiation from a light-emitting diode (LED), comprising:
providing a pulse-width modulated (PWM) signal to the LED, the PWM signal having current pulses with a duty factor, a pulse width, an amplitude, and a frequency; adjusting the duty factor, the pulse width, the amplitude, and/or the frequency of the current pulses to provide a forward voltage, Vf, which corresponds with a target junction temperature, Tj, of the LED; and measuring, when the target junction temperature is obtained, the optical radiation of the LED during a current pulse.