Description
What is a transparent PCB?
Transparent PCB can also be called clear PCB, and this unique circuit board not only has potential for aesthetically designed products but also advantages in optical applications.
It is unlike the traditional normal PCB, the transparent PCB has high transparency. It consists of the transparent substrate, conductive layer, and insulation layer.
there are different types, such as transparent glass PCB, Transparent flex PCB, and transparent rigid (FR4) PCB.
Different kinds of transparent PCB
| Transparent Flex PCB | Transparent Fr4 PCB | Transparent Glass PCB | |
| Material | Transparent PET | Transparent Fr4 | Borosilicate/Quartz Glass |
| Transparency | 80%-90% | 50%-70% | High >90% |
| Flexibility | Bendable | Rigid | Rigid |
| Temperature Resistance | -40°C~160°C | Tg 130°C~180°C | 500°C~1000°C |
| Dielectric Properties | Medium | Medium | Low Dk/Df, Excellent High-Frequency Performance |
| Fragile | Medium | Hard | Easy |
1, Transparent FR4 PCB
As we know, the normal FR4 is made of fiberglass cloth and epoxy resin, which don’t have transparency. To achieve the light transmission of the FR4, we need to adjust the resin formula, such as using transparent epoxy resin or adding transparent fillers. It keeps the FR4’s mechanical strength, heat resistance, and electrical insulation. We can make a 1-6-layer transparent FR4 PCB, and the copper thickness can be made from 1-3oz. It is easy to produce, and the cost is low. However, the transparency is limited.
2, Transparent Flex PCB
The common FPC materials are yellow, black, and white, and they are used in different kinds of applications. While the transparent flex PCB uses the high transmittance PET film as the substrate, it can be used in transparent displays, 
transparent screens, and solar.
As it is bendable, foldable, and weightless, it is suitable for wearable devices also; this is other transparent PCB can meet it. However, the disadvantage is that the PET material’s heat resistance is not so good, and it is easy to deform at high temperatures. The high signal loss at high frequencies makes it not suitable for 5G/RF applications.
3, Transparent Glass PCB
It is a new material for the PCB, using glass as the PCB substrate instead of traditional materials like FR4 or polyimide. It offers high transparency, high temperature resistance, and excellent high-frequency performance. The glass substra
te has low dielectric loss, a smooth surface, chemical and moisture resistance, making it suitable for advanced optoelectronic, HDI& Microelectronics, and high-frequency applications. The disadvantage is that this technology is not mature, and it can only make 1-2 layers. The transparent glass PCB cost is high, and it is easy to break compared to other transparent PCBs.
FX PCB is a supplier for different kinds of transparent PCB, send us your inquiry or requirments today, and we will quote you soon!
