Flashing or non-flashing IR emitter
When you select an IR emitter, you will often have the choice between one that flashes and one that does not. Selecting an emitter that flashes lets you detect easily whether the control system is transmitting or not. However, using a flashing IR emitter can present problems that are more difficult and time-consuming to resolve.
To get the visible flash and still be able to control IR devices, the frequency of the light that the IR emitter emits must be on the edge of visible light and IR light – a wavelength just around 800 nm. However, the most common wavelength used by remote controls is 940nm. The difference between 940nm and 800nm is often the reason why certain IR devices are unresponsive even though the IR emitter is flashing.
The non-flashing IR emitters transmit IR signals using a 940nm wavelength. If you want a more powerful IR signal, use a non-flashing emitter. There will always be cases where the IR device reacts to both IR emitters. However, when using the flashing emitter, the control of the device will likely be less reliable. If you use an IR emitter that does not flash you will be less likely to encounter unnecessary problems.