Coupling a Fiber to the MS257

Some fibers feature two options, where the fiber may be held against the slit or may replace the slit. This option is available for fibers that have rectangular or "slit-like" terminations. If the rectangular slit width is greater than that of the input slit, it is suggested to use the fiber with a slit in order to maintain the desired resolution.

Both standard and quick connect ferrules have an outer diameter of 11 mm. The difference is the way they mate to the fiber holders themselves. The Quick Connect ferrules maintain fiber orientation, even after removal and re-insertion, as well as X, Y and Z alignment.

The use of dual track fibers or other types of fibers for imaging applications requires special consideration because of the magnification introduced by the spectrograph. The instrument's magnification, plus its optical aberrations, magnify the image dispersed over the detector. If the image height is taller than the detector, spectral information will be lost. The MS257 has a vertical magnification of 1.5x.

If throughput is critical, consider using the model 77259 F/# Matcher to improve efficiency. It converts the F/2 of fused silica fibers to F/4, the acceptance cone angle of the MS257 Spectrograph. The 77259 F/# Matcher is specifically designed to maintain the imaging properties of multi-track fibers. Please note that the images are magnified by a factor of 2.0. The detector must be large enough to accommodate the entire magnified image. When these fibers are used with the MS257 and the F/# Matcher, the final composite image height will be magnified by a factor of 3.5 (1.5 by the Spectrograph and 2.0 by the F/# Matcher).