In the field of LED lighting and LCD backlighting display, the diffuser sheet plays a key role in softening and evenly spreading light. Commonly used materials for diffuser sheets include PC (polycarbonate), PMMA (acrylic), and PS (polystyrene). So, what are the differences between them, and how do you choose the right one?
This article will help you understand the working principle of diffuser sheets, the material differences, and how to select the best one for your application.
1. What Is a Diffuser Sheet?
A diffuser sheet is a flat plastic panel used in lighting systems and display panels. It is produced by adding light-diffusing agents into base materials like PC, PMMA, or PS. These sheets help to scatter and spread light rays, reducing glare, hot spots, and uneven brightness.
Diffuser sheets are widely used in:LED backlight modules,LCD displays,Commercial lighting systems,LED Light boxes, home appliances, and control panels…
2. Optical Principle of Light Diffuser Sheet
The working mechanism of a diffuser sheet is based on the scattering and refraction of light. When light enters the sheet:Microscopic optical diffusing particles alter the path of light rays.This increases the beam angle and spreads the light more uniformly.The surface appears soft, bright, and foggy, which enhances aesthetics and reduces eye strain.
It also boosts energy efficiency by minimizing wasted light and reflections.
Well-designed optical diffuser sheets help improve light output while protecting human vision.
3. Comparison of PC, PMMA, and PS Diffuser Sheets
Though all three materials serve similar purposes, they differ in optical clarity, mechanical strength, and thermal/fire resistance. Here’s a detailed comparison:
| Key Property | PC Diffuser Sheet | PMMA Diffuser Sheet | PS Diffuser Sheet |
| Light Transmittance | 80% | 85%-90% | 60%-85% |
| Haze | 93% | 94% | 90% |
| Weight | 1.2 kg/m² | 1.2 kg/m² | 1.05 kg/m² |
| Bending Strength | > 100 MPa | > 70 MPa | > 50 MPa |
| Fire Resistance | UL-V0/V2 Rated (Flame Retardant) | Not Fire Rated | Not Fire Rated |
| Common Size | 1220 × 2440 mm | 1220 × 2440 mm | 1220 × >2440 mm |
Feature &application guidance
PC Diffuser Sheets (Polycarbonate Light Diffuser Panel)
Product Features:
1)Extremely high impact resistance, suitable for harsh environments
2)High flame retardancy, high heat deflection temperature, UL-certified
3）Good dimensional stability, suitable for precision processing
4)Relatively expensive, double-sided protective film increases labor time
5)Excellent strength, high heat resistance, flame retardant
Application:industrial lighting, outdoor applications, and safety zones
PMMA Diffuser Sheets (Acrylic LED Diffuser Sheet)
Product Features:
1)High light transmittance (up to 90%)
2)Excellent weather resistance, no yellowing for 3-5 years indoors
3)Excellent screen printing and spraying performance, suitable for decorative lighting fixtures
4)Diverse forming processes, including thermal forming, laser cutting, and vacuum forming
5)Moderate impact resistance, higher than PS but lower than PC
6)High light transmittance, elegant appearance, aging-resistant
Application:display backlights, commercial lighting, advertising signs
PS Diffuser Sheets (Polystyrene Light Diffuser Plate)
Product Features:
1)Lightweight and cost-effective
2)High refractive index with a wide range of haze adjustment
3)Low static electricity, resistant to dust accumulation, and scratch-resistant surface
4)Easy to process, suitable for large-scale production
5)Poor weather resistance, not recommended for outdoor use
Application:indoor use, budget-friendly lighting products
4. We Are a Professional Diffuser Panel Manufacturer
As a trusted diffuser panel manufacturer, we specialize in producing high-quality PC, PMMA, and PS diffuser sheets with flexible customization.
We offer:
Wide material selection for optical diffuser sheets
Custom sizes, thicknesses, haze levels, and transmittance options
Full support for OEM / ODM projects
Reliable quality, fast delivery, and expert technical support
Contact us today to request a quote of our custom diffuser plates!