Acrylic Light Guide Plates & Panels (LGP)
Custom PMMA light guide plates for edge-lit displays and LED backlighting.
CLAREX light guide panels are custom-designed to distribute light from customer-supplied edge-lighting units. Each panel is made from clear optical-grade CLAREX cast acrylic/PMMA and printed with a custom dot pattern using reflective white ink.
The dot pattern is custom engineered around your panel size, LED placement, lighting configuration, and illumination goals to help optimize brightness and uniformity across the backlit area. Patterns can be designed for full-area illumination or selective backlighting, such as individual keys, buttons, icons, or display zones. Each custom light guide panel is designed for specific applications and will incur development charges.
Note: CLAREX light guide panels are best suited for smaller display applications, up to approximately 24″ diagonal. Larger-format panels should be reviewed with Astra’s team to determine feasibility.
Benefits of Acrylic (PMMA) Light Guide Panels & Plates
Custom Dot Pattern Design
Each dot pattern is designed around your lighting unit, panel size, LED placement, and illumination goals.
Uniform Light Distribution
CLAREX light guide panels can help spread edge light evenly across the illuminated area, with typical 70% uniformity using a 9-point measurement method.
Improved Display Brightness
The printed light extraction pattern helps direct light where it is needed, supporting brighter and more visually consistent display backlighting.
Energy Efficient Edge-Lit Illumination
The dot patterns can be designed to backlight an entire area uniformly, or they could be used to only backlight certain spots, such as backlighting the individual keys on a keyboard.
Full-Area or Zone-Specific Lighting
Dot patterns can be designed to illuminate an entire panel or only specific areas, such as keys, icons, indicators, or display sections.
Optical-Grade Acrylic LGP Construction
Panels are made from clear CLAREX cast acrylic/PMMA, providing a high-quality optical base for custom backlighting applications.
APPLICATIONS
Common Light Guide Panel Applications
Formulated for compact small to medium edge-lit displays, backlighting, and illumination applications that require controlled light distribution.
Edge-Lit LCD Backlights
Custom light guide panels for compact LCDs and display assemblies that require thin, uniform backlighting
Selective Backlighting
Dot patterns can be designed to illuminate specific areas, such as keys, buttons, symbols, or display zones.
Small Display Backlights
Used in electronic displays, instrumentation, and specialty display units where space is limited and light needs to be distributed evenly.
Keypads & Keyboard Backlighting
Suitable for backlighting individual keys, buttons, or control surfaces in compact electronic assemblies.
Control Panels & User Interfaces
Used in panels, buttons, and operator interfaces where controlled lighting improves readability and usability.
Specialty Illuminated Components
Custom light guide plates for compact lighting assemblies, indicators, and other application-specific illuminated parts.
Sample materials may be available to help you evaluate material performance.
Design Considerations
Light Guide Panel Design Considerations
Light guide panel performance depends on the complete lighting assembly. Panel thickness, LED placement, mixing space, supporting optical layers, and mechanical clearances should be considered together when developing the dot pattern.
Acrylic/PMMA Material & Panel Thickness Options
CLAREX optical-grade cast acrylic provides excellent long-path light transmission for custom backlighting applications.
- Light guide panel thickness options range from 0.2mm to 5.0mm.
- The light guide should be thicker than the height of the LEDs. Thicker LGPs improve efficiency but require a larger mixing area.
Light Guide Panel/Plate Sizes
- Generally used for small/medium displays (under 24″ diagonal) due to the costs and limitations of the process we use.
- Customizable per customer specification. Contact us to discuss options.
Material & Dot Pattern Design
Optical-grade acrylic and custom dot patterns help create uniform light distribution across the panel.
- Manufactured using CLAREX optical-grade clear cast acrylic for excellent long-path light transmission.
- Provides superior thermal stability compared to commercial-grade acrylic.
- Custom dot patterns are designed around the lighting unit configuration, including 1-, 2-, 3-, or 4-sided lighting and individual point sources.
- Dot pattern is silk screened onto the rear surface using a proprietary reflective white ink.
- Dot size and density typically increase with distance from the light source to help maintain uniform illumination.
Stack-Up & Mechanical Fit
The surrounding assembly should account for reflector and diffuser layers, LED spacing, and acrylic thermal expansion.
- Light guide panels are typically used with a reflector layer behind the LGP and a diffuser layer in front.
- Reflector and diffuser layers are not included and should not form an optical bond with the LGP when stacked.
- The gap between the LEDs and the LGP should be minimal, while still allowing room for expansion. Restricting outward expansion can cause the panel to bow in the center.
- Because CLAREX acrylic expands when heated, the panel should be sized to account for maximum expansion and tolerance stack-up within the lighting unit.
LED Positioning, Edge Treatment & Light Control
LED layout, edge quality, and light containment all affect brightness, uniformity, and overall optical performance.
- The LEDs’ horizontal luminous spread angle and pitch (separation) should be considered to avoid dead zones along the panel edge.
- A light mixing area between the panel edge and active display area is recommended whenever possible, with LED spread overlapping into the active area.
- CLAREX can adjust the dot pattern to compensate for minor layout limitations or limited mixing space, but dead spots near the edges are best avoided through proper LED positioning.
- A clean machined edge often performs better than a polished edge because slight diffusion can improve uniformity.
- Mirror tape may be used on unlit edges to help reflect light back into the LGP, though effectiveness can be limited by adhesive transmission loss.
- CLAREX does not use diffuser tape or film on lit edges. While it may possibly improve uniformity, there is a loss of light input, and ultimately may not be worth the extra cost.
Dual-Mode Lighting Considerations
For systems with multiple lighting modes, one mode should be defined as the primary design target.
- If two emitter sets are used, such as day and night modes, one must be selected as the “primary mode.” The primary mode should guide the dot pattern design.
- The secondary mode can often be improved through dot pattern adjustments, but may not reach the same level of uniformity.
- Best practice is to configure both lighting modes so they can benefit from a common dot pattern whenever possible
HOW IT WORKS
How Do Light Guide Panels & Plates Work?
Light is directed into the edge of the LGP, where it is ‘captured’ and guided through the panel via internal reflection.
This light will continue to travel through the panel until it either reaches the opposite side or encounters a surface disturbance, such as a printed dot of reflective white ink, which directs the light to the desired location.
FAQs
Light Guide Panel Frequently Asked Questions
What information do you need to quote a custom light guide panel?
Share your panel dimensions, preferred thickness, LED layout, and the areas you want to illuminate. Include any brightness or uniformity requirements, space constraints, and drawings of the assembly so Astra can review the design.
Can a light guide panel illuminate only certain areas?
Yes. Custom dot patterns can direct light to selected keys, buttons, icons, or display zones rather than illuminating the entire panel. The pattern is developed around your lighting configuration and application requirements.
Does the light guide panel include LEDs, reflectors, or diffusers?
No. CLAREX light guide panels are designed for customer-supplied edge-lighting units. Reflector and diffuser layers are separate components and are not included with the panel.
Are there development charges for custom light guide panels?
Yes. Each panel requires a dot pattern designed for the specific application, so custom designs incur development charges. Astra can review your requirements and discuss the development scope.
Find the Right Light Guide Panel for Your Application
Share your panel dimensions, target thickness, LED layout, active illumination area, and brightness or uniformity requirements.
Our team can review your application and help determine a suitable CLAREX light guide panel configuration.