The Art of PCB Design: Beyond the Green Rectangle

Introduction

Not all electronic boards are created equal!

The printed circuit board, PCB, or electronic board is often perceived as a purely functional component in the world of electronics: it’s just a green rectangle with components on it. At BLUEGRioT, we have a different vision. For us, the PCB is an opportunity for artistic and technical expression. By relying on concrete examples, we demonstrate that the PCB can be much more than a simple support for components.

The Union of Art and Technology in PCB Design at BLUEGRioT

At BLUEGRioT, PCB design is an art form that requires a unique approach combining technical skill and creativity. This philosophy allows us to transform ordinary PCBs into aesthetic and functional objects, pushing the boundaries of convention in the world of printed circuits.

Composition of a PCB!

Let's start with a simple 2-layer PCB. ☺️

A PCB is a stack of materials and layers, each having a specific role. The base is often made of FR4, a glass-reinforced epoxy resin chosen for its robustness and thermal stability. On top of this, layers of copper (for the tracks) are applied, followed by a colored solder mask (very, very, very often green, but it can be other colors as seen in the photo below), and finally silkscreen (usually white). The silkscreen is used to write labels like R1 or R2 to identify resistors, outline a zone, or display a logo.

Let's Make Something Simple: A Business Card!

For our PCB business card project, we opted for a simplified approach, focusing mainly on aesthetics. By playing with the different layers of the PCB, we explored four distinct colors, but the possibilities don't stop there, as we will see later. Although the card is primarily intended for visual use, we added a single component: a small 1kΩ SMD resistor. This component, though discreet, plays a key role, acting as a design element on the character's shirt.

This choice illustrates our ability to blend design and functionality in our PCBs. Indeed, it would be entirely possible to integrate advanced features, such as Bluetooth communication, light emission via LEDs, or even NFC technology, simply by adding a power source. The potential of an electronic board is vast, and we are ready to explore all these possibilities.

Play of Light, Transparency, and Color Nuances

In the classic design of an electronic board, the applied solder mask plays a key role in the visual aspect of the product. Take, for example, the green varnish used in our project. This unique hue is not limited to a single green. In reality, the color varies subtly depending on what lies beneath: either copper or directly the FR4 substrate.

We exploit this variation to create visual effects, like the reflections in the character's hair on our card. In the illustration, we see that the copper layer (represented in yellow) has empty spaces in the hair area. However, the green varnish covers this entire zone, creating a slight nuance in the green tones. This subtle play of colors and materials contributes to the overall aesthetic effect of the card.

The exploitation of transparency constitutes a distinctive element in our PCB designs. By deliberately choosing not to apply copper, varnish, or silkscreen on certain parts of the board, we open the way to fascinating plays of light, enriching our creations with an innovative visual dimension.

In our specific "business card" design, we took care to leave the character's face entirely clear—without copper, varnish, or silkscreen—leaving the raw FR4 exposed. The slight translucency of the FR4 offers us a unique opportunity: by also preserving the opposite side of the card, we can create light effects through the card. And that is exactly what we achieved. On the back of the card, the oval surrounding the character is also left as bare FR4, which produces a striking visual effect and demonstrates the versatility of the PCB in creating artistic effects.

The Art of PCB at DEF CON

In the DEF CON community, the art of PCB badges is an iconic practice that perfectly illustrates the fusion between technology and creativity. These badges, far from being simple identification tools, embody a unique culture, valuing innovation and ingenuity in printed circuit board design.

DEF CON, with its focus on the hacker community and technological creativity, offers an interesting parallel with the Forum InCyber (FIC), a major event in Europe centered on cybersecurity. Located in Lille (our home turf), the Forum InCyber will take place from March 26 to 28 and will address similar topics, particularly cybersecurity. I'll be wandering around there with my super badge 🤓.

Conclusion

When it comes to designing PCBs for products in the industrialization phase, innovation in design—particularly the creative use of copper tracks—must be approached with caution 😬.

Indeed, routing rules are strict to guarantee product reliability and longevity, while respecting European standards for CE marking. However, this does not mean the end of creativity. Silkscreening offers a playground where artistic expression can flourish without compromising product performance. At BLUEGRioT, we fully embrace this opportunity, allowing our PCBs to stand out for their aesthetics without sacrificing their efficiency and compliance.

The design video