When designing lamp covers, two commonly used transparent materials are PC (Polycarbonate) and PMMA (Acrylic). At first glance, they look similar—both clear and almost glass-like—but their performance is quite different: one is more impact-resistant, while the other is more optically pure. Choosing between them depends on the lamp’s intended use and performance requirements.
Zhang, a lighting designer, was recently developing a desk lamp for a client who emphasized “impact resistance,” as the lamp was mainly for young families. He tested both PC and PMMA samples. When he lightly dropped the PMMA piece, small cracks immediately appeared along the edges. The PC sample, on the other hand, only had minor scuff marks and remained intact. Zhang laughed, saying, “PC is definitely the safer choice—no worries if kids knock it over.” Ultimately, he chose PC, which provided both safety and sufficient light transmission.
Key Performance Comparison of PC and PMMA
| Property | PC (Polycarbonate) | PMMA (Acrylic) |
|---|---|---|
| Light Transmittance | ~88–90%, visually close to glass | ~92–93%, higher optical clarity |
| Impact Resistance | Very high, ~200 times stronger than glass | Only ~1/10 of PC, prone to cracking |
| Heat Resistance | Up to ~120°C | Typically ~80°C, prone to deformation |
| Cost | Slightly higher | Relatively lower |
| Processing | Suitable for injection molding and thermoforming; complex structures possible | Easy to cut and polish; glossy surface, ideal for decorative parts |
| Typical Applications | Protective covers, car lights, outdoor lamps, impact-resistant lighting | Display cases, decorative lamps, optical components |
Both PC and PMMA can serve as transparent lamp covers, but their differences in key properties directly affect safety and durability.
- Light Transmittance: PMMA is slightly higher, producing purer light, while PC’s 88–90% is sufficient for most lighting applications.
- Impact Resistance: PC is extremely tough, unlikely to break if dropped; PMMA is brittle and prone to cracking. This explains Zhang’s decision to use PC for a child-friendly desk lamp.
- Heat Resistance: Long-term lamp operation generates heat. PC can withstand around 120°C, whereas PMMA may soften above 80°C.
- Processing & Cost: PMMA offers a glossy finish ideal for decorative lamps; PC allows complex structures, with slightly higher cost but greater durability.
Typical Application Scenarios
- Children’s Desk Lamps / Bedside Lamps: Children may knock over lamps during play. PMMA can shatter, while PC is like a “safety helmet” for your lamp.
- Outdoor Garden Lamps / Street Lights: Exposure to wind, rain, and occasional impact favors PC, whereas PMMA is more likely to crack or deform.
- Commercial Display Lamps / Decorative Lighting: When visual effect matters, PMMA’s crystal-clear quality shines—but only in stable, low-impact installations.
In short:
- Prioritize safety and durability → choose PC
- Prioritize visual appearance → choose PMMA
Conclusion
If you’re unsure whether to choose PC or PMMA, our engineers can assess your product needs, provide sample testing, and recommend the best material. This ensures your lamps are safe, durable, and visually appealing. After all, no one wants a desk lamp to break from a simple bump. Talk to an engineer now.
