Fiber optic bundles for railway lighting and display applications
Multi-end fiber bundles with defined exit points
A common coupling end, multiple precise light exits for digit and symbol projection in robust track systems.
Fiber optic multi-end bundles for precise light distribution in railway systems
Railway and infrastructure applications place special demands on optical components: light must arrive precisely where it is needed, the geometry must be repeatable, and the assembly must be reliably integrated into robust housings. Fos Inon manufactures custom fiber optic bundles for railway lighting and display applications – especially multi-end bundles, where a common coupling end distributes the light to several defined exit points.
This architecture is ideal when the light source is to be placed centrally (e.g. for thermal, space or maintenance reasons), but the light outputs are required at several positions in a display or lighting unit.
Fiber optic bundles for speed indicators: digital digit projection with defined points
One focus is on fiber optic bundles for speed indicators in railway applications. Here, multiple precisely arranged light exit points (“points”) are implemented so that a digital number can be displayed or projected onto the display unit. The bundle has multiple ends on the display side (multi-end) and a common end for light coupling. This allows a single light source to be used, while the light distribution is precisely focused on the required points or segments of the digit.
Crucially, the exit points must be reproducible: positions, distances, and final design are manufactured according to specifications to ensure consistent representation within the system – from prototype to series production. This results in optical solutions that can be integrated into existing display platforms while simultaneously enabling defined, controlled light guidance.
Configuration according to system requirements instead of a standard product
Our fiber optic bundles are not conceived as a “one-size-fits-all” component, but rather as a configurable element within your overall system. Depending on the installation situation, digit layout, and desired appearance, the length, fiber structure, number and arrangement of exits, and termination details can all be customized. The design of the common coupling end is also tailored to the intended light source and the mechanical interface.
Equally important is mechanical protection in the railway environment: bundles can be designed with suitable sheathing and protective concepts to ensure reliable routing, assembly, and operation within the device. The goal is a solution that is visually clean, mechanically easy to assemble, and operationally reliable.
Further applications in the railway sector
Besides speed indicators, fiber optic solutions are suitable wherever precise light distribution is required and central light sources offer advantages. Typical applications include status and symbol displays, illuminated pictograms, and control and indication points in infrastructure enclosures. Fiber optics can also help in retrofit projects, modernizing existing display or lighting platforms with clearly defined light distribution without fundamentally altering the overall system.
If you need light points, lines or defined exits at multiple positions in a railway project, a multi-end bundle is often the structurally elegant solution: a central light coupling, several precise light exits – with clear geometry and good integration capability.
Collaboration: quickly from idea to series production
The most efficient approach begins with a brief technical consultation: What type of display is to be implemented, what digit/dot geometry is planned, what is the available installation space, and what light source will be used or is planned? Based on this, we propose a bundle design and a final geometry that is optically and mechanically suitable for the application. A prototype can then be created for system verification. If the display and integration are satisfactory, the design is standardized for series production – including defined test criteria to ensure consistent quality.
Why Choose Light Guides from FOS Inon Fiber Optics?
Quality “Made in Germany” pays off. Thanks to our proprietary manufacturing and testing processes, we offer custom solutions for numerous applications, from laboratories to aerospace.
Manufacturing Process
To ensure our light guides and fiber optic products meet the highest standards, we rely on a specialized manufacturing process. This allows us to guarantee exceptional chemical and tactile robustness so they can perform optimally in their respective environments. Precision is a critical factor in this, true to our motto: “Making the impossible happen.”
Materials Used
- Borosilicate: Glass with high temperature resistance and chemical resilience.
- PMMA (Polymethylmethacrylate): A thermoplastic, lightweight plastic with high light transmittance.
- Silica-Hard Clad: A robust plastic coating for improved strength and durability.
- Silica-Silica for UV and NIR Wavelengths: Our specialized glass fibers, optimized for the transmission of light in the ultraviolet (UV) and near-infrared (NIR) ranges.
PMMA is a thermoplastic material, known under brand names such as Plexiglas or acrylic glass. In fiber optics, PMMA is used for:
- Flexible, cost-effective fiber optic cables are used
- Large core diameters (up to several millimeters)
- Applications using visible light
PMMA fibers are less temperature-resistant than glass fibers (max. 70-100°C), but significantly more flexible and less expensive. This makes them a particularly good choice for lighting or sensors where extreme temperatures are not present.
Borosilicate (also called “boron glass”) is a special type of glass with a high boron oxide content. It is the same material used to make heat-resistant laboratory glassware and baking molds. In fiber optics, it offers:
- Excellent chemical resistance to acids and alkalis
- Good temperature resistance up to approximately 400-500°C
- Low thermal expansion (less stress during temperature changes)
Ideal for standard industrial applications and lighting.
Optional Specifications:
- Various apertures available
- Polarization can be maintained
- Anti-reflection coating possible
- Various lengths, diameters, bending radii, converters, and vacuum feedthroughs optional
- Various connectors and ferrules suitable for industry and medicine
SMA (Sub-Miniature A) is a standard screw-type connector for fiber optic cables, designed for laboratory equipment and spectrometers. The connector has a 1/4″-36 thread. FSMA is the fiber optic version with a specially protected ferrule for the sensitive fiber end face. Standardized connectors allow you to connect our cables directly to your equipment, or we can manufacture custom connectors for your specific application.
Silica-silica fibers consist entirely of high-purity quartz glass (silicon dioxide), both the core and the cladding. This construction offers:
- Extremely high temperature resistance up to 1000°C
- Optimal transmission in the UV range (below 300 nm)
- Excellent transmission in the NIR range (1000-2500 nm)
- Minimal absorption losses
Therefore, these fibers are primarily used in high-performance lasers, UV curing, and spectroscopy.
Request a project
If you already have a layout, a sketch, or a rough specification, that’s enough to get started. The following are particularly helpful:
- Application (e.g. speed indicator, symbol or status display)
- Number and arrangement of exit points (sketch/file)
- Installation situation, desired bundle lengths and routing
- Light source (if known) and desired interface at the coupling end
- Demand (sample, pilot, series)
Send us your sketch or specification – we will get back to you with a concrete proposal for structure, geometry and implementation.
Do you need further information, a customized quote, or expert advice for your project? We are always available to assist you.
Reliability doesn’t happen by chance.
At FOS Inon Optics, quality is not just a promise—it is a standard that can be measured. Our development and manufacturing processes for fiber-optic systems are ISO 9001:2015 certified. This establishes the foundation for reliable performance, reproducible results, and trust wherever optical precision is critical.
