iTechGuides is reader-supported. When you buy through links on our site, we may earn an affiliate commission. As an Amazon Associate I earn from qualifying purchases. Learn more
A desk-fan persistence-of-vision (POV) display uses LEDs on a rotating arm and switches them at precisely timed positions to make text or graphics appear in the air. A project reported by Hackster uses a desktop fan’s motor to spin the arm, with an Arduino Nano, Hall effect sensor and magnet, LEDs, a LiPo battery and motor in the build. It is not simply a matter of sticking lights on any fan blade: the mounting, power, timing and balance all have to work together.
How a rotating LED display makes an image
A POV display relies on the persistence of vision: as LEDs move, the eye retains their light briefly. If the controller switches LEDs on and off at carefully chosen angular positions during each rotation, the moving points of light form lines, letters, numbers or graphics. As Hackster writer Cameron Coward puts it, “By carefully controlling when the LEDs are turned on and off, you can form letters, numbers, or even graphics.”
The controller needs a timing reference so it knows where the rotating assembly is. In the desk-fan project reported by Hackster, a Hall effect sensor detects a magnet once per revolution. That reference lets the Arduino estimate rotation speed and time the LED updates. Other designs use different sensing arrangements; the documented POV-fan project, for example, uses an infrared sensor to track rotation. A Hall sensor is therefore one approach, not a universal requirement.
Recommended Free Tools
What the reported desk-fan build includes
Hackster’s report on TN_inventor’s tutorial describes LEDs carried on a rotating arm spun by a desktop fan’s motor. The listed components are an Arduino Nano, Hall effect sensor and magnet, LEDs, LiPo battery and electric motor. The report says the Arduino and battery are placed on the arm and that the rotating assembly needs to be well balanced.
#1 Best Overall
- Small floor or tabletop fan: Honeywell TurboForce Air Circulator Fan is a cooling fan that is 25% quieter than comparable fans.** It’s sized to be a table or desk fan or wall-mounted, and provides cooling in small to medium-sized rooms
- Feel the power: Honeywell TurboForce fans have an aerodynamic turbo design to maximize air movement and power for intense cooling or energy-saving air circulation. You can feel the power of this small floor or desk fan from up to 25 feet away
- Customize your comfort: With 3 speeds and a 90° pivoting adjustable head, you’ll always be comfortable and cool! Customize your cooling to however you like with this powerful and quiet fan. #1 selling table fan
- Smart savings: Quiet fans for bedroom and home are an easy way to cool down any space and improve airflow. Give your air conditioner a break by using a portable indoor fan to help reduce your energy consumption and costs
- Honeywell quality: Help improve cooling and energy savings in your home or office using a Honeywell personal desk fan. Honeywell has personal fans for bedroom, whole room fans, tower fans, and oscillating fans that are a great choice
These details describe that project, not a verified recipe for every desk fan. The Instructables tutorial linked from the report could not be independently checked for its exact fan model, dimensions, wiring or assembly sequence. The report also does not establish that a fan’s existing blades can carry the same display arrangement. Treat the component list as an example system whose parts and mounting must be compatible with the particular motor and support.
Other fan-based POV architectures
Projects that use fans differ in what rotates, how the electronics are powered and how position is sensed. These examples show possible design choices; none establishes drop-in compatibility with an ordinary desk fan.
Rank #2
- Classic Design & Small Size: Classic design and more compact, less than 8 ounces, take up small space; it's very suitable for home, car, office, outside or traveling
- Quiet Operation: The fan is very strong and the noise is less than 50dB even when a strong wind is provided; at work and rest, this is a good friend who is quiet and comfortable for you
- Three-Speeds Setting: Low/medium/high-speed setting; press the power button repeatedly to adjust the appropriate fan speed(Note Please: 3rd speed, need to make sure the power source is 5V/1A )
- Adjustable Wind: The fan head can rotate vertically from 0 to 30 degrees, providing the most suitable angle wind to quickly cool you down
- High Compatibility USB-powered: Compatible with PC/laptops, mobile power, AC adapters, car chargers, and other power supplies that support USB
| Example | Rotating support and controller | Power and sensing | What the example shows |
|---|---|---|---|
| Desk-fan build reported by Hackster | LED arm spun by a desktop fan’s motor; Arduino Nano | LiPo battery on the arm; Hall effect sensor and magnet | A fan motor can spin a separately described LED arm, but the report does not validate arbitrary fan modifications. |
| Box-fan display by Han Li and Emily Sun | DotStar LED strip on a plywood arm; PIC32 microcontroller | 5 V battery bank and 9 V battery; Hall effect sensor | The authors used the box fan’s rigid base as a platform rather than building a separately calibrated DC-motor rotation setup. See Circuit Cellar. |
| PC-fan display reported by Hackaday | Self-contained rotating module with Neopixels and Arduino | Onboard battery and radio avoid slip connections | A compact arrangement can carry its electronics with it; the report also describes a rough build in which acrylic flex led to added support. See Hackaday. |
| Custom fan documented on GitHub | Custom blade with STM32/Nucleo and ESP32 controllers | Infrared rotation sensing and separate motor-speed control | The project separates display control, rotation sensing and speed control; its documentation notes physical stability at high speed as a challenge. See the project documentation. |
The box-fan authors explain their platform choice this way: “As such, the box fan serves as an ideal platform for a POV display, without needing to construct a well-calibrated rotating setup with a DC motor.” That rationale applies to their described build, not to fans in general.
Crashes, No Sound, or Screen Glitches?
Random freezes, missing sound and display glitches usually trace back to one bad driver. Find and replace yours safely.Free scan · under a minuteWindows Errors? Fix Them Before They Spread
Repair common Windows errors and clear accumulated junk for a smoother, more stable PC - no reinstall needed.Free scan · no reinstallWhat determines image quality and timing
Image clarity and refresh depend on the display geometry, LED arrangement, timing and the fan’s actual rotation behavior. A sensor reference helps the controller align image slices with each revolution, but it does not make one project’s resolution or refresh figures transferable to another.
Rank #3
- Small floor or tabletop fan: Honeywell TurboForce Air Circulator Fan is a cooling fan that is 25% quieter than comparable fans.** It’s sized to be a table or desk fan or wall-mounted, and provides cooling in small to medium-sized rooms
- Feel the power: Honeywell TurboForce fans have an aerodynamic turbo design to maximize air movement and power for intense cooling or energy-saving air circulation. You can feel the power of this small floor or desk fan from up to 25 feet away***
- Customize your comfort: With 3 speeds and a 90° pivoting adjustable head, you’ll always be comfortable and cool! Customize your cooling to however you like with this powerful and quiet fan. #1 selling table fan*
- Smart savings: Quiet fans for bedroom and home are an easy way to cool down any space and improve airflow. Give your air conditioner a break by using a portable indoor fan to help reduce your energy consumption and costs
- Honeywell quality: Help improve cooling and energy savings in your home or office using a Honeywell personal desk fan. Honeywell has personal fans for bedroom, whole room fans, tower fans, and oscillating fans that are a great choice
For their 2018 box-fan project, Han Li and Emily Sun reported these results and component details:
- About 7 Hz on the fan’s slowest setting, equivalent in their article to about 143 milliseconds per rotation.
- 100 angular tick locations in the display timing scheme.
- A refresh rate around 14 Hz in their example, achieved by lighting the LEDs twice per fan rotation.
- Positioning variation of up to 2.5 degrees during their testing, which they linked to interrupt timing, the Hall sensor and the 100 display angles.
- About 60 mA per LED at full intensity for their DotStar strip, driven at 5 V.
These are figures from one project’s reported setup and testing, not general POV requirements, guarantees for a desk fan or specifications for other LED products.
Rank #4
- Powerful air Circulation for your entire room: Dreo's WingBoost system combines deep-pitched blades and aerodynamic design to propel air as far as 70 ft, helping your desk fan to circulate strong air throughout your whole room. Product Dimensions: 10.8''D x 9.5''W x 11.8''H，Blade Diameter: 7 inches
- Feel wind without noise: If you are looking for a silent table fan to enjoy blowing but quiet sleep, this is a fantastic choice, by integrating NACA technology and bionic design, this home bedroom fan moves air more efficiently and reduces noise down to 25dB, perfect for a comfortable night.
- Save energy every season: Pair it with multiple appliances to increase efficiency and reduce your energy bills. Air circulators increase the effect of ,space heaters, humidifiers, and purifiers by moving the air faster around the whole room.
- Functional than traditional fans: With 3 built-in speeds by knob control, you can find the right setting easily; whether you are across the living room or want to place your floor fan in front of your bed, you can always get the comfort you need.
- Super easy to clean, always ready to go: You can use this tabletop fan straight out of the box, hang it on the wall for uninterrupted air circulation, or use it in multiple rooms with its extra convenient base and handle design. Parts can also be easily removed for cleaning to keep your air always fresh.
Plan the assembly as one system
Before choosing parts, decide what the fan or motor will actually support and how the display electronics will rotate. The component names alone do not establish that parts are electrically or mechanically compatible.
- Rotating structure: Determine whether the display is an arm driven by the fan motor, a module attached to a fan, or a custom rotor. Mounting stiffness and balance affect how reliably it rotates.
- Position reference: Choose a sensing method, such as a Hall sensor and magnet or an infrared sensor, that gives the controller a repeatable rotation reference.
- Power and data: Decide whether electronics travel on the rotating assembly with an onboard battery or use a suitable slip-connection arrangement. Each choice changes weight, wiring and complexity.
- LEDs and resolution: Select LEDs and an arrangement that match the controller’s timing and available power. More LEDs or finer angular timing do not automatically produce a clearer image.
- Controller and features: An Arduino Nano is the controller named in Hackster’s report; the box-fan example uses PIC32, and the custom GitHub project uses STM32/Nucleo and ESP32 controllers. User input and separate motor-speed control can add complexity.
No controlled head-to-head comparison establishes one architecture as best. The design choice depends on the fan or motor, rotating support, power strategy, sensing method and the display you intend to make.
Best Value
- COMPACT DESIGN: Measuring just 6.3 x 11.1 x 10.9 inches (LxWxH) with three 7-inch blades, this fan occupies minimal space on floors or tables, perfect for various room types such as bedrooms, living rooms, home offices, and kitchens. Enhance airflow and keep cool wherever you are
- ADJUSTABLE TILT: Enjoy personalized airflow with a 90-degree variable tilt feature, allowing you to direct the airflow precisely where you need it
- 3 SPEED SETTINGS: Easily adjust the fan speed to your preference with intuitive settings (0, 1, 2, 3) using the back-mounted control knob. Choose between low, medium, and high speeds for tailored comfort
- PORTABLE CONVENIENCE: Weighing only 3 pounds, this fan is effortlessly portable, making it convenient to move around your home to wherever cooling relief is needed
- ENERGY EFFICIENT: Save energy without sacrificing performance. With 35 Watts at 120V, this fan provides efficient airflow to help keep your space comfortable while reducing energy costs
Safety limits and practical caution
A rotating arm carrying a battery and electronics can introduce mechanical and electrical hazards. The cited project reports do not establish a safe added mass, operating distance, speed limit, enclosure design or electrical-safety procedure for a particular household fan. Their descriptions should not be treated as certification that a modified fan is safe.
Do not operate a modified fan on the assumption that balancing it by eye is sufficient. Before operation, verify the fan and motor design, mounting strength, clearance, wiring and guarding against the fan’s authoritative product documentation and competent engineering guidance. If those checks cannot establish that the assembly is suitable, do not run it.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
Free tools Windows power users keep installed
One-click scans. No signup required.
