We recently had the chance to review a really cool USB Led Fan, one that can print a message or time in air! The USB Mini Flexible Time LED Clock Fan retails for around $5.5 and as the name suggests, its very flexible. Not only you can attach it to computer or laptop, but you can also run it with a power bank. Apart from the time (or in this case, temperature – amazon link), it also gives a decent amount of breeze, enough for 1 person to cool off in hot weather. We tried many versions, one with a red led, blue led or the one with multicolored leds.
The multicolored led (green and red) is excellent for time, the blue led one displays custom message and the temperature in Celsius and the red led one is programmable and can display any message (6 paragraphs at the most, each paragraph can have a maximum of 16 characters)
Since its USB powered, not only can you attach it to your computer or laptop, you can even attach it to a power bank (like the video above, where the power bank is hidden beneath the base) or directly to the AC plug using a DC USB adapter. The noise is very minimal and it works best in the dark or when there is a dark background (so if you are using this for advertising in your shop, keep this in mind).
The video below shows a blue colored USB fan being run from a power bank (hidden beneath the base)
How Does The LED USB Fan work?
The concept behind this is ‘Persistence of vision”. The way it works is, there is thin long strip on one of its blades that has a IC and some leds. Lets say you want it to float a message saying ‘1’, what the IC will do it, turn on the led only where the letters are supposed to appear and shut it off as soon as it passes that point. Since the fan is spinning very fast and our eyes can only manage a certain number of frames per second, it seems that the message is ‘solid’, i.e. What we perceive is a blend of what we are viewing at that instant and what we saw a fraction of a second before.
If you play it in very slow motion, all you will see is a very confusing display of some LEDs going on and off. You can even make it yourself if you are a bit technologically inclined. Download the instructions PDF from this link made by some students.
Buy The USB LED Fan
Click here to buy the programmable one at a discounted price of ($5.5) with free shipping all over the world. If you would rather buy it from Amazon instead of Aliexpress, click here to buy it ($13). These fans normally retail for above $8 on ebay and even above $15 on some famous gadget websites
- Small, Portable
- Compatible with all USBs
- Not easy to read in bright sunlight