How to Choose the Color of a Fiber Optic Sensor

Fiber optic sensor color selection depends on the application, object surface, and standard color coding for identification, with options for visible or infrared light and TIA-598-C fiber color standards.

Color Detection in Fiber Optic Sensors

Fiber optic sensors detect color by measuring the wavelength of reflected light from an object. Light from the sensor is transmitted through the fiber to the object, then reflected back to a photodetector, which converts it into an electrical signal. Different wavelengths correspond to different colors: shorter wavelengths appear bluer, longer wavelengths redder. Detection methods include comparison (matching to preset reference colors) and triangulation (measuring RGB intensities to compute precise color coordinates) for higher accuracy and adaptability .

Choosing Sensor Light Color

When selecting a fiber optic sensor for color detection, consider the following:

• Visible light options: Red, green, blue, or other visible wavelengths are used for detecting specific colors on objects .
• Infrared light: Useful for detecting objects regardless of visible color, or for applications where ambient light may interfere .
• Surface properties: Glossy, transparent, or structured surfaces may require sensors with specialized optics to reduce reflection errors and improve detection accuracy .

Fiber Color Coding for Identification

For multi-fiber cables, TIA-598-C standard defines a 12-color sequence for easy identification:

1. Blue
2. Orange
3. Green
4. Brown
5. Slate
6. White
7. Red
8. Black
9. Yellow
10. Violet
11. Rose
12. Aqua For cables with more than 12 fibers, the sequence repeats using a tube and fiber system, where the outer buffer tube has a color and the individual fiber inside follows the 12-color sequence. This ensures error-free identification in high-density installations .

Practical Considerations

• Application distance: Some sensors, like FCL SPECTRO, can detect colors from distances up to 500 mm, useful for distinguishing glossy vs. non-glossy surfaces .
• Fiber type: Glass fibers offer durability and heat resistance, suitable for harsh industrial environments .
• Custom requirements: Fiber jackets can be customized in RAL colors or printed with legends for project-specific identification . By combining the correct sensor light color, fiber type, and TIA-598-C color coding, you can achieve precise color detection and reliable fiber identification in industrial and high-density cabling applications.