Light guides are made to easily direct light from one place to another without having to worry about complicated optics setups.
An individual fiber consists of the core (to guide the light), the cladding (to create the necessary refractive index change for total internal reflection), and a coating (to overcome the brittleness of a bare fiber). The cladding is made from the same material as the core, but has been doped to create the necessary change of refractive index.
Each light guide is built from either a single fiber or a bundle of fibers according to the acceptable levels of light loss and how tightly the light guide might have to be bent. The light guides are made with the required optical diameter and length, with considerations including the protective jackets, connectors, temperature ranges.
tec5USA works closely with our customers to design light guides best suited to their application. To show the possible customizations, we have summarized some of the most important features below, as further reference please use our Product Information Brochure. The Specification Sheet provides a printable guideline of what information is necessary to finalize a design of a specific light guide.
Light Guides Handling & Quality Properties
Fiber Material - Transmission Range
The fiber material defines the useful spectral range
• UV Quartz: 240 - 950 nm
• UV-Stabilized Quartz: 190 - 950 nm
• NIR Quartz: 350 - 2200 nm
• Other materials upon request
Fiber Coatings - Temperature Range
The fiber coating is decisive for the temperature range, for extreme cases, it can be even stripped.
• Acrylate: -40°C to 85°C
• Silicone: -40°C to 150°C
• High T Acrylate: -40°C to 200°C
• Polyimide: -190°C to 385°C
• Other materials upon request
Fiber Diameter
Larger diameters are usually stiffer and have a lower bending radius. A few of the standard diameters are:
• 200 μm • 50 μm
• 400 μm • 80 μm
• 600 μm • 105 μm
• 800 μm • 150 μm
• Other diameters upon request
Note: the coating is generally 5% of the diameter, and the core-cladding ratio is 1.1 (UV fibers) or 1.2 (NIR fibers). NA is 0.2, others on request.
Bundle Arrangements and Diameter
A bundle consists of a multitude of thinner fibers to make the light guide more flexible or to allow bifurcation. The fill factor causes about 40% loss of light. Additional losses may occur when a fiber bundle is couple to another bundle. A mix of fibers is possible - including various diameters or materials. Bundles up to various mm in diameter are possible.
Ramifications
Fiber bundles can be split into several arms. A simple 1:2 split is called a bifurcation. A multifuraction consist of more than 2 arms.
• Number of Splittings: 2 to almost unlimited
• Combination of all types of fibers, bundle diameters, lengths, and terminations
Fiber Length
Long light guides can become very expensive as the cost is determined by the amount of fiber material used.
• 50 mm to 100 m
• In deeper UV and longer NIR fiber damping is higher, use length as short as possible
• All arms can have different length
Connectors
Any type of connectors can be provided as they are all made in house. The SMA and the 4x20 mm ferrule are the most widespread.
- F-SMA905
- Ferrule, ∅4x20 mm, other dimensions on request
- Coding on request
- Other terminations available upon request
Jackets
Jackets provides protection for the fibers. All types of sheathing can be used. The most common sheathing is called SA quality, which is made with a metal spring and a thick rubber jacket.
• Heavy duty (SA)
• Lab quality (SZ)
• Vacuum Sheathing (no rubber)
• Other Jackets available upon request