Ocean Optics S1024DW Install - Manual (Page 50)

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Fiber Optic Probes and Accessories: T200 Transmission
Probes
T200 T RANSMISSION D IP P ROBES couple to our spectrometers and light sources to create small-footprint
optical-sensing systems for measuring transmission in chemical solutions and other liquids. The standard
T200 has 1 illumination fiber and 1 read fiber and a 0.25” outer diameter stainless steel ferrule. The probes
come with either a fixed or removable tip (2-mm, 5-mm or 10-mm path length removable tips).
Caution!
" " " " Handle with care. Dropping the instrument may cause permanent damage.
" " " " Bubbles will interfere with your readings. Regularly inspect the sample region for bubbles.
Operation
The T200 Transmission Dip Probe consists of two identical fibers in a bifurcated assembly. A plano-convex
lens shapes the light coming out of the illumination fiber. The light is transmitted through the sample, hits the
mirror, reflects off the mirror, and interacts with the sample again before being transmitted back through the
probe via the read fiber. Because the light travels through the sampling region twice, the optical pathlength is
actually twice the length of the sample aperture. The transmission cell is used to measure absorbance of the
fluid that fills the sample compartment between the fibers and the mirror, which is a UV-enhanced aluminum,
second-surface mirror.
1. Connect one leg of the probe to the light source and connect the other leg to the spectrometer. It does
not matter which leg of the probe is connected to the light source or spectrometer.
2. In order to achieve the best signal, use an Allen wrench to loosen the set screw on the inner fiber barrel
assembly and slide it up and down to change the intensity of the light returned until a signal in Scope
Mode reaches approximately 3500 counts. The position of the inner barrel has been optimized at the
time of manufacture for aqueous media applications using a 10 mm tip. If your application requires
measuring gases you will have to move the inner barrel for maximum throughput.
3. Immerse the probe in distilled water or the solvent of your choice and take a reference spectra.
4. Remove the probe from the reference material, block the light path going to the spectrometer and take
a dark spectrum. (Do not turn the light off.)
5. Make sure the light path is clear, place the probe in your sample solution and take your sample spectra.
To replace the probe tip, simply unscrew the probe tip and screw in either a 2-mm path length, 5-mm path
length, or 10-mm path length replaceable tip for the Transmission Dip Probe.
Specifications
Fiber core diameter: 200
µ
m
Fiber core/cladding: Silica
Fiber bundle: 1 illumination fiber and 1 read fiber
Numerical aperture: 0.22
Optimization: UV/VIS (200-750 nm) and VIS/NIR (450-1000 nm)
Ferrule: Stainless steel or plastic, 3.75” x 0.25”
Terminations: SMA 905
Probe assembly length:
2 meters (breakout is halfway); custom probes are also available
1 meter for plastic ferrule option