align="justify">Whever attention needs to be gained, it’s normal practice to flash LEDs. In addition to attracting the eye, flashing LEDs also considerably drops battery consumption.

Let’s look at the second point. If the light has a similar on and off time – say 1 second on, 1 second off – it is said to have a 50 per cent duty cycle. Straightaway, we’ve approximately halved the power consumption of the light! But what if we drop the duty cycle of the flashes below 50 per cent? In fact, what if we run a 20 per cent duty cycle? Now we’ve saved about 80 per cent of the power!

But if the light is off for 80 per cent of the time, will anyone see it? Yes they will – if you make the flashing frequency high enough. In other words, a very short duration flash that occurs rapidly will work brilliantly at getting attention but will have energy consumption far lower than if the light was on continuously.