Accessories Z-Dimensions Are Not Created Equal Cuvettes come in a variety of shapes and sizes, but one of the most important specifications of a cuvette is its Z-dimension. The Z-dimension of an instrument (cuvette holder or spectrometer) is the distance from the bottom of the cuvette chamber floor to the center of its light beam (see image). A cuvette’s Z-dimension must match the Z-dimension of the instrument with which it will be used. Fiber Optic Collimator SPEC TROS CO PY Each manufacturer designs its instruments with a specific Z-dimension. Common Z-dimensions include 8.5 and 15mm, and sometimes 20mm. When purchasing small volume cuvettes, the correct Z-dimension becomes critical. Matching the Z-dimension of the cuvette to the Z-dimension of the instrument ensures that the light beam passes through the center of small samples. The table below shows the standard Z-dimension of the spectrometer sample compartments for many manufacturers. Manufacturer Z-Dimension Agilent® 15 mm Avantes® 15 mm Beckman® 8.5 mm Bio-Rad® 8.5 mm Cecil® 15 mm Eppendorf® 8.5 mm Hewlett – Packard® 15 mm Hitachi® 8.5 mm Jasco® 11 mm J & M® 8.5 mm Ocean Optics® 15 mm Perkin – Elmer® 15 mm Pharmacia® 15 mm Shimadzu® 15 mm Spectronics® 8.5 mm Stellarnet® 15 mm Turner® 8.5 mm Varian ® 20 mm WPI 15mm To determine the Z-dimension of a cuvette holder: ● Use strips of heavy paper that will fit neatly into a cuvette (for example, 12mm x 50mm) and not allow light to pass through the cuvette. ● Poke a tiny hole in each paper “sample.” For example, one paper sample could have a hole at 8.5mm, one at 15mm, one at 20mm. ● One at a time, insert the paper samples into the cuvette and place the cuvette into the cuvette holder. The paper sample with the pin hole at the instrument’s Z-dimension will allow light to pass. The other paper samples will not allow light to pass. If you have an instrument that is not on the list and need to know its Z-dimension, please contact WPI at 941-371-1003 or technicalsupport@wpiinc.com. WPI’s Fiber Optic Collimator can be used for both collimating a light beam emitted by an optical fiber or coupling light from a collimated light beam into an optical fiber. The numerical aperture of the collimator is optimized for maximum coupling efficiency into typical fused silica fibers. The collimator can, for example, be used to guide a parallel light beam through a sample cuvette or an optical filter with virtually no optical losses. In this application, one collimator collimates the light into a parallel beam 5 mm in diameter, enabling it to pass a long distance without losing the energy. After the light passes the sample media, a second collimator can be used to collect the beam into the receiving fiber. A unique design feature of this collimator is that the distance between the lens and the optical fiber can be easily adjusted. This permits it to be used as a focusing device or for fine-tuning the color balance when coupling light from a light source into multimode fibers. COLLIMATOR Specifications LENS DIAMETER LENS FOCAL DISTANCE LENS MATERIAL 1) WAVELENGTH RANGE MOUNTING THREADS DIVERGENCE FIBER CONNECTOR INTERFACE 5 mm 10 mm Ultraviolet grade synthetic fused silica (KU220 nm-2 µm 3/8-24 UNF < 0.1 rad for 1 mm core fiber SMA or ST 300051 300052 Fiber Optic Collimator (SMA) Fiber Optic Collimator (ST) OPTIONAL ACCESSORIES 13395 SMA Bulkhead Feedthru connector/coupler, D-hole 13370 SMA half-length Bulkhead coupler/connector CC-3-UV Cosine Corrector CC-3-UV 13395 13370 198 UK: Tel: +44 (0)1462 424700 • wpiuk@wpi-europe.com World Precision Instruments www.wpiinc.com Germany: Tel: +49 (0)30-6188845 • wpide@wpi-europe.com US: Tel: 941-371-1003 • sales@wpiinc.com