A fiber Optics is a “tube of glass” which can transport light, with almost no loss and no degradation. This system allows us to separate the spectroscope (which spreads out the light) from the telescope (which collects it).
The Fiber Optics proposed by Shelyak Instruments are optimized for Astronomy, and especially for the eShel system.
Main specifications are :
Attenuation < 0.5 dB,
- Multimode fiber, numerical aperture: NA = 0,22
- Core diameter : > 50µm for the fibers “Object” > 200µm for the fibers “Calibration”
- Standard lengths: 5, 10, or 20m. Other lengths longueurs (up to 50m) upon request.
- The fiber is protected by a tubing, made by extrusion, to ensure the best resistance (the tubing hold the traction efforts)
- Stainless steel shield of diameter 5mm, ensures optimal protection… even during the night (nos risk of damage if you walk on the fiber).
- Connectors of type FC at each end. This is a connector with an index, ensuring a constant angular position when unplug-replug the connector.
i.e. the transmission is above 90%. Note: the loss in fiber optics is mainly at the ends, with the connectors. The transmission of the fiber itself, up to some dozens of meters, is close to 100%. As a consequence, this attenuation value (<0.5dB) is valuable whatever is the length (5, 10, or 20m). Since October 2017, the fibers optics “Objects” (50µm) are of type “High-OH”, offering very good performance in the blue part of the spectrum. These fibers can be used from 380 to 800nm, or even above.