Light Guide Products for Automotive Applications

Our automotive power window switch lenses offer a lighting solution that combines high visibility and excellent light uniformity within limited

A standout feature of this product is its ability to illuminate 5 to 7 switches using just one LED. This innovative design supports greater freedom in cabin design while contributing to space and component reduction. By eliminating the need for multiple LEDs, we also eliminate color inconsistency (chromatic deviation) across switches, ensuring consistent light quality throughout.

Our proprietary light guide technology enables efficient light branching and diffusion within the lens, even from a limited light source. This achieves a uniform luminance distribution, supporting intuitive, low-stress operation for both driver and passengers. The highly visible illumination also helps prevent operational errors at night or in low-light conditions, thereby enhancing safety.

Moreover, the ability to illuminate multiple switches with fewer light sources contributes to energy efficiency, making it well-suited for electric and hybrid vehicles where energy management is critical.

From a design perspective, we offer meticulous customization of lens shapes and surface finishes to ensure harmony with the vehicle's interior styling. We provide flexible custom designs to meet the diverse needs of OEMs and Tier 1 suppliers.

Our light guides for instrument panels provide a high-luminance and uniform lighting solution that balances visibility and premium aesthetics. Using advanced in-house optical design technologies, we develop light distribution tailored to each vehicle model and interior concept, creating a refined and comfortable cabin environment.

Recent automotive trends call for extended ambient lighting across the full width of the instrument panel and functional integration with infotainment systems for dynamic information display. These demands require enhanced light uniformity over long distances and high luminance levels to ensure intuitive visibility for the driver and occupants.

To address these requirements, our optical design minimizes light loss from the input to the distal end of the guide. Even with a 1,000mm-long light guide, we achieve smooth and uniform brightness using just one LED at a single end. Normally, increasing brightness leads to intense light concentration near the input and noticeable brightness drop-off or unevenness toward the center and end. However, through precision prism processing and optimal placement of diffusing elements, our design maintains a continuous and elegant light line throughout.

These light guides are also highly compatible with next-generation applications such as information signaling and alerts through lighting, enabling enhanced interactivity and user experience.

Designed to clearly indicate the location of cup holders even in low-light conditions, this illumination solution enhances both comfort and peace of mind for vehicle occupants. Light emitted from a single LED is evenly diffused around the entire circumference of the cup holder through a light guide featuring blast-processed surfaces. This ensures uniform and seamless illumination without hotspots.

The light guide is engineered with high transparency and carefully applied surface treatments to blend harmoniously with the vehicle interior. The result is a soft, direct light that gently surrounds the cup holder, reducing visual strain during nighttime driving or while placing or removing drinks.

Through repeated optical simulations, we minimize variations in light distribution, achieving a uniform glow from every viewing angle. This not only ensures functionality but also contributes to a luxurious and aesthetically pleasing cabin atmosphere.

Our design maximizes efficiency, illuminating a wide area with a minimal number of LEDs, offering both cost-effectiveness and flexible integration into various vehicle models. Despite its simple appearance, every detail has been thoughtfully considered, delivering a balance of function and style that elevates the overall driving experience.

USB port illumination gently highlights charging and connectivity ports, enabling smooth operation even in darkness or low-light environments. It enhances user convenience by making USB ports easy to locate without fumbling, especially when connecting smartphones or other devices. By precisely illuminating only the necessary area, it maintains the tranquil lighting atmosphere of the cabin while offering functional, refined visibility.

Leveraging our expertise in light guide design, we achieve uniform illumination of multiple areas from a minimal light source. This compact and highly efficient setup helps reduce component count and supports energy-saving vehicle systems.

The light guide features carefully crafted optical geometries that deliver soft, glare-free light while maintaining sufficient brightness for clear visibility. It prevents discomfort from direct viewing and ensures a smooth, intuitive interaction with the USB port.

As a discreet yet impactful lighting feature, USB port illumination combines functionality and aesthetic finesse, subtly but effectively enhancing the overall in-vehicle user experience.

This illumination system highlights the position of the seat belt buckle, providing intuitive visibility and smooth usability even in the dark or at night. It plays a vital role in enhancing both safety and convenience for passengers by ensuring clear recognition of the buckle during entry and exit.

The optical design is carefully engineered to deliver optimal light distribution, enabling users to fasten their seat belts easily and without hesitation. The area around the buckle is uniformly illuminated, improving operability and reducing stress. Since the light is positioned within the driver’s or passengers' direct line of sight, particular attention is given to prevent glare or uneven brightness, resulting in a soft yet clearly visible glow.

Only one high-efficiency LED is used to keep power consumption low while maintaining sufficient brightness. Light emitted from the LED is guided evenly around the buckle via a transparent resin light guide. Prism processing on the light guide enhances brightness uniformity and widens the viewing angle.

Despite the limited space around the buckle, our design achieves high luminance uniformity while maintaining a compact configuration. This seat belt buckle illumination not only prevents operational errors, contributing to safety, but also enhances the overall user experience. It is a sophisticated lighting solution that supports safe, comfortable journeys through precise optical engineering and smart spatial integration.

Our illuminated emblems enhance brand identity by making vehicle logos vividly visible even in dark or low-light environments. More than just decorative elements, these emblems act as striking visual features that combine visibility with brand presence, making a lasting impression on the user.

Ideal for premium models or vehicles with a strong design emphasis, our illuminated emblems reflect the quality and refinement of the brand. The lighting and reflection control are finely tuned to highlight the emblem with clarity, elegance, and consistency.

Thanks to our fully integrated in-house production system—from design and mold fabrication to mass production—we can respond quickly and flexibly to prototype development and precise mold adjustments. This ensures both speed and precision in product development, while maintaining high standards of quality and reliability.

The result is an emblem that functions as a “light icon” on the front face of the vehicle, clearly expressing the brand’s presence, enhancing the vehicle’s premium feel, and contributing to a sense of ownership pride for the user. Our emblem lighting is a fusion of technical excellence and aesthetic appeal that elevates the overall value of the vehicle.

Rear seat illumination provides passengers with a sense of calm and luxury by emitting a soft, ambient light that blends seamlessly into the rear cabin space. Beyond creating a relaxing atmosphere during travel, it plays an essential role in elevating the overall in-vehicle ambiance.

Utilizing an optical design that distributes light in a smooth line formation, even from a limited number of LEDs, the lighting spreads naturally across seat surroundings and side panels. This ensures both enhanced visibility in low-light conditions and gentle, eye-friendly illumination. Light uniformity is maintained without compromising the interior’s visual quality.

Combining functionality with aesthetic appeal, this lighting solution integrates quietly into the cabin and transforms everyday rides into special experiences of comfort and refinement.

Our map light guide is mounted above the front seats and is engineered to gently and accurately illuminate the passenger’s hands or work area. Unlike conventional straight-down lighting, our unique optical structure enables diagonal light distribution, directing light precisely where needed for a more pleasant in-cabin experience.

The lens structure—developed using our patented technology—refracts light from the LED at an angle within the guide, allowing even centrally placed light sources to effectively illuminate the target area. This design increases design flexibility while achieving bright, uniform light with minimal light sources, significantly improving usability at night or while reading.

We also offer an advanced version: the Pinhole Light Lens, which emits light through a discreet 2mm opening. It delivers sufficient brightness when active and maintains exceptional hidden appearance when off, making it ideal for seamless interior designs. Its compact size also contributes to greater installation flexibility, especially in premium or EV interiors where refined ambiance is essential.

This lighting solution provides not only excellent illumination performance but also superior design integration, energy efficiency, and spatial optimization—supporting our commitment to blending optical control, design aesthetics, and functionality in automotive lighting.

Our roof illumination system offers a soft, natural glow that envelops the cabin, enhancing the sense of space and safety without overwhelming the vehicle's interior. Designed to deliver subtle, high-quality light, it integrates seamlessly into the ceiling and supports both visibility and ambiance.

Even with a limited number of light sources, our optical design ensures uniform brightness across a wide area, balancing energy efficiency with high performance. The structure supports long linear illumination, providing elegant lighting across the ceiling without obstructing passenger views. Indirect placement avoids direct glare, creating a calm and relaxing light environment.

A particularly striking application is ambient lighting around the sunroof, where soft illumination harmonizes with the open roof to create a luxurious and serene space, day or night. At night, the glowing light line adds a quiet visual accent, enriching the driving experience.

This lighting enhances the cabin’s perceived quality and serves as a signature element that reflects the brand identity—suitable for everything from premium models to compact vehicles.

The front and rear door line illumination enhances both visibility and aesthetics, creating a unified lighting experience that defines the vehicle's character. Positioned along the door contours, this lighting not only highlights door handles and trim for easy access, especially in dark environments, but also adds a touch of sophistication to the cabin.

Using an optical structure designed to deliver smooth and even illumination across the entire line with minimal light sources, the light guide’s shape and surface treatment are precisely engineered to eliminate brightness inconsistencies. The result is a seamless glow that outlines the door silhouette and deepens the sense of interior harmony and depth.

While many vehicles offer front door illumination only, adding rear door lighting enhances the premium feel and design consistency throughout the cabin.

Thanks to our fully integrated production system—from design proposals to prototyping and mass production—we can provide rapid, customized solutions for various vehicle models.

Front and rear door line illumination combines function and design at a high level, offering passengers visual comfort and a refined spatial experience, while reinforcing the vehicle's brand image and perceived quality.