POV Display

A 2D display made with a rapidly rotating single row of LEDs.

Letters are displayed in dot matrix format by blinking a spatial portion at a time followed by next.

The effect is that the image is perceived as a whole by the viewer as long as the entire path is completed during the visual persistence time of the human eye.

ATMega328 is used to control the blinking of LEDs and the code is burned into the microcontroller using an Arduino UNO.

The circuit diagram is drawn in a laterally inverted manner so that while etching the circuit we get desired orientation. I used 8 LEDs so the diagram is designed to accommodate 8 LEDs. Arduino is only used to burn the code to the microcontroller. A separate system is included in the circuit for the functioning of ATMega328.

A 1000rpm motor was used, the rpm of the motor is significant as the delay in the code needs to be adjusted correspondingly.

The power supply for the circuit is given by a 9V DC battery and the motor is given a separate power supply.

List of components(Left to right):
1. Photodiode

2. 3 x 1K ohm resistors

3. 2 x (BC548)transistors (for switching circuit)

I've used a standard power supply unit including the rectifier circuit which could be omitted.

4. Reset switch

5. 28 pin narrow DIP IC Socket

6. 16MHz Crystal Oscillator

7. 2 x Ceramic 0.1uF Capacitors

7. 8 x LEDs

8. 8 x Resistors (pick one ideal for the color of LED used)

The cicuit design is photo-printed and embossed on the copper-coated wafer.

The black lining is the printer ink which masks the circuit during the next step.

The printed board is dipped in FeSO4 solution. As a result, all the copper other than the masked region is washed away.

One should be careful while drilling the hole for rotor-head as the center of mas after the attachment of 9V battery should be taken into consideration to maintain equilibrium.

Then the tiny holes for components are drilled using suitable drill bits.

Then the components are soldered into position.

The code is burned into the microcontroller using an Arduino UNO board and it's carefully placed in the circuit.