Acrylic and Polycarbonate – The Preferred Material Choices for LED Light Pipe Applications
Light Emitting Diodes (LEDs) have clearly emerged as the premier technology choice for indication and lighting solutions. While the technology has evolved, so have the materials that go into the finished product. Plastics, especially acrylic and polycarbonate, have become the “materials of choice” because of the performance and versatility they provide.
The needs of design engineers for LED components typically include a variety of considerations such as:
- Protecting the costly LED light source and other board mounted components
- Ensuring flame resistance, adherence to thermal requirements, and long term heat stability
- Functioning in high vibration environments
- Optimizing light intensity and clarity (or diffusion)
- Offering great design freedom and high manufacturability
Very few materials can fulfill these needs. Acrylic and polycarbonate are used in a variety of LED applications because they have the balance of properties to meet these varied requirements.
Acrylic and polycarbonate are lightweight, tough, plastic materials with outstanding optical properties. Both are easy to mold into complex shapes. These characteristics make them good choices for LED light pipes, particularly for applications where superior optical properties, durability, and strength are required.
Acrylic generally has superior optical properties compared with polycarbonate. It offers the highest light transmission of any plastic material, is good for the diffusion of LED hot spots, and is easy to mold. Acrylic is also naturally UV stable for outdoor use (and available in grades with enhanced UV stability).
Polycarbonate is tougher and more durable than acrylic. It can operate at a higher temperature, and has superior flammability characteristics. Polycarbonate has good light transmission, excellent diffusion of LED hot spots, and offer impact resistance along with good heat resistance. Polycarbonate is also available in UV stabilized grades that are engineered for outdoor use.
In summary, both acrylic and polycarbonate offer solid light delivery performance when used in light pipe applications, and the product application requirements will typically drive the designer to which is more appropriate for their design.
Need help designing a light pipe? Contact a VCC application engineer today.
Frequently Asked Questions
How do I select the right plastic material for my light diffusing application?
There are a number of things to consider when selecting a plastic material for a light light pipe application. These include the type of light source being used, the potential for impact, flammability requirements, outdoor exposure, and the service temperature range.
Most plastics used in light pipe applications are clear or translucent white, however many different color choices are available including red, yellow, blue, and orange.