Various Liquid Light Guides
If you need high light throughput anywhere in the UV to NIR, our Liquid Light Guides are the smart choice. They are more efficient and less expensive than Fused Silica Fiber Bundles, and you dont have to worry about fiber breakage! Weve expanded our line to include DUV light guides, which transmit down to 220 nm and bifurcated models for selected wavelength ranges.
For dual source applications, we offer bifurcated liquid light guides. The single end does not meet into a common circular core; the two cores are stacked in the common end (see Fig. 3). Each leg has an active core of 3 mm and a length of 39 or 79 inches (1 or 2 m). We can also supply trifurcated liquid light guides; contact us for details.
The acceptance angle of our liquid light guides is significantly higher than for our Single Branch Fiber Bundles. This means you get significantly more throughput from the same core diameter. The geometrical extent (a measure of fiber optic light gathering capability) of a 3 mm diameter UV-VIS liquid light guide is 8.5 mm2; that of a 3.2 mm diameter fused silica fiber bundle is 1.1, and that of a 3.2 mm diameter glass bundle is 7.6.
These light guides are robust and long-lived in normal use. They consist of a plastic tube covered by a protective aluminum spiral and covered by a PVC jacket. The inner tube is filled with a proprietary, transparent, anaerobic, non-toxic fluid. The tube is sealed at both ends with polished fused silica or glass windows and protected by an interlocking stainless steel sheathing.Like all our fiber optics, these have 11 mm ferrules on the ends so they fit in our Rod Mount for Fiber Bundles. To ensure long life, the temperature at the input face should not exceed 40 °C. Also, the UV-VIS models should not be exposed to wavelengths shorter than 300 nm, the VIS models to 340 nm, and the VIS-NIR to 420 nm.
We offer these liquid light guides as yet another alternative for delivery of the DUV output from our deuterium and arc lamps. Choose a liquid light guide when you need maximum throughput and the large core diameter of these guides is not a concern. For small point sources, 1 mm or less, we offer Solarization Resistant Fibers. We compare the transmittance of a 5 mm diameter liquid light guide to a typical quartz fiber bundle, in Fig. 2. DUV liquid light guides have a limited lifetime. Formation of bubbles in the liquid leads to a significant drop in throughput. Storage in a cold and humid environment extends the lifetime. The long term operational temperature range of these guides is 5 to 30 °C. Table 1 shows the average useful life of the DUV light guides.