FEBRUARY 28, 2007 -- Integrated Photonics Inc. (IPI) has announced that it is the first company to offer a lead-free Faraday rotator (search for Faraday rotator) to OEM customers. While the company reports that all its Faraday rotator materials (FLL, FLM, FLT, and MGL) are RoHS compliant (<1,000 ppm lead), the MGL material is designed to be lead-free.
Thick-film Faraday rotators are the principal components in nonreciprocal passive photonic devices (search for photonic devices) such as optical isolators (search for optical isolator) and circulators and can also be used in magneto-optic switches, variable optical attenuators, and sensors. They are critical to the performance of fiber-optic systems because they have high Faraday rotations in the infrared telecommunications wavelengths. Therefore, they do not require long path lengths and/or bulky magnets that strongly affect device cost, size, and performance.
According to IPI, the MGL Faraday rotator does not require a bias magnet at all. It has been tested in a variety of harsh environments and still maintains the single-domain configuration, allowing it to be placed in locations that would previously have been considered out-of-bounds because of magnetic field, packaging, weight, size, and thermal mass constraints. The company says the composition of the MGL material is optimized to sustain latching performance over a wide temperature range and is based on patents licensed and held by Integrated Photonics.
Thick-film Faraday rotators are grown by liquid phase epitaxy (LPE) from a flux that typically contains lead oxide. IPI says it has developed proprietary technology with a high degree of process control to reduce the lead that enters the crystal to a value below the RoHS limit in all materials and to zero in the MGL material. IPI's materials have been thoroughly tested using ICP-MS by two independent third-party testing laboratories and are certified to be in full compliance with the RoHS Maximum Concentration Values (MCVs). The company reports that this development has caused the European Union to open a consultation on eliminating the exemption for lead in Faraday rotators (see http://ec.europa.eu/environment/waste/rohs_6_consult.htm, Item 21), which closed January 10, 2007, without opposition and is currently under review.
IPI will be exhibiting at the Optical Fiber Communication Conference & Exposition and the National Fiber Optic Engineers Conference (OFC/NFOEC) in Anaheim, CA, March 27–29, 2007, at booth number 3360.
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