Material Selection for Optical Functional Components

17.03.2025

Choosing the right plastic for optical functional components is crucial to ensuring high quality, mechanical stability, and durability. Optical plastics are used in precision applications such as lenses, lighting systems, and sensors, where specific properties must be met.

Transparent Plastics in Injection Molding: Properties and Requirements

High-quality optical functional components require materials with excellent transparency, precise refractive index, and good UV stability.

Two of the most commonly used materials are PC (Polycarbonate) and PMMA (Polymethylmethacrylate, also known under trade names like Plexiglas).

Both are well-suited for injection molding but exhibit different characteristics:

PMMA (Polymethylmethacrylat)

• Highest transparency and optical purity
• Color neutrality
• Excellent scratch resistance
• Increased hardness, but more brittle and prone to breakage
• Low heat resistance, making it less suitable for high-temperature applications

PC (Polycarbonat)

• High transparency
• Slight color tints (yellowish or bluish)
• UV stability can be improved with additives
• Lower hardness but flexible and impact-resistant
• High impact strength and heat resistance

Comparison: PMMA vs. Polycarbonate

The choice between PMMA and PC depends on specific requirements. PMMA offers the highest transparency and is ideal for applications with low mechanical stress. Polycarbonate, on the other hand, is the best choice for applications requiring high temperature and impact resistance.

High-Performance Thermoplastics for Optical Applications

Beyond PMMA and PC, other thermoplastic materials are also used, particularly for demanding optical components.

Optimizing Material Selection

The optimal material choice for optical precision components considers:

• Transparency and refractive index for precise optical performance
• Heat resistance to prevent deformation
• Scratch resistance for long-lasting surfaces
• UV stability, especially for outdoor applications
• The need for coatings to enhance performance

Conclusion: Which Material is Best for Optical Plastic Components?

The answer depends on the application. PMMA is often the first choice for precise and scratch-resistant applications, while PC excels in high-impact environments. For extreme conditions, high-performance plastics are recommended.

The right material is the foundation for the performance and longevity of your optical plastic components. The experts at VIAOPTIC are happy to assist you.

Picture Copyright: VIAOPTIC GmbH, Bettina Schwehn