Coherent sources of light are those sources that emit a light wave having the same frequency, wavelength, and in the same phase or they have a constant phase difference.
A coherent source forms sustained interference patterns when superimposition of waves occurs and the positions of maxima and minima are fixed.
LED
A light-emitting diode(LED) is a semiconductor device that emits light when an electric current flows through it.
Is an LED a coherent light source?
No, an LED is not a coherent light source because even if they do have waves that have the same frequency, these waves will not be in phase with each other.