Hollow-glass, infrared bundles for coherent imaging

所提出的工作的总体目标是开发中空波导技术，以制造用于宽带红外成像的低损耗、相干图像束。采用的方法是制造中空玻璃，相干束，然后可以涂覆用于宽带红外传输。图像束将使用芯棒包裹和浸出束技术制造。使用空心氧化玻璃管形成束的优点是，用于固芯玻璃纤维的常规相干束法可以在这里使用。一旦相干中空导束制成，玻璃管的内壁将使用罗格斯大学开发的两种技术进行涂层。第一个是液相化学，第二个是化学气相沉积（CVD）。这些方法已被证明非常成功地制作了损耗低至0.1 dB/m、长度达13 m的单波导。该项目的挑战是将目前用于覆盖孔径小至250微米的单个空心导轨的技术扩展到约50 ~m孔径的导轨，这将构成红外图像束。本研究的意义在于，通过多层介质涂层的沉积，中空玻璃波导的损耗预计将减少10倍或更多。开发出一种高效的、用于2 ~m以上成像的相干红外束将标志着首次制造出如此高分辨率的宽带红外束，人们相信，这项技术将对用于识别和过程控制的热成像系统产生重大影响。如果我们成功地将空心波导的损耗减少到电流损耗的十分之一，我们不仅将拥有一种非常适合热成像的光纤，而且还将拥有一种具有巨大潜力的波导，可以为外科手术和其他医疗应用提供激光功率。此外，我们的空心包既可以用于发送模式，也可以用于接收模式。也就是说，可以传输激光能量用于局部加热，然后通过同一光纤束来询问产生的热能。最后，通过相同的空心导束，应该可以制造出包括热成像、电力传输和化学传感在内的终极智能光纤

9874115HarringtonThe overall objective of the proposed work is to develop the hollow waveguide technology necessary to fabricate low-loss, coherent image bundles for broadband infrared imaging. The approach to be taken is to fabricate hollow-glass, coherent bundles which then can be coated for broadband infrared transmission. The image bundles will be fabricated using both mandrel wrap and leach bundle technologies. The advantage of using hollow oxide glass tubing to form the bundles is that conventional coherent bundling methods used for solid-core glass fibers can be used here. Once the coherent hollow guide bundles have been made, the inside walls of the glass tubing will be coated using two technologies developed at Rutgers University. The first is liquid-phase chemistry and the second is chemical vapor deposition (CVD). These methods have proven very successful in making single waveguides with losses as low as 0.1 dB/m and lengths up to 13 m. The challenge in this program is to extend the current technology used to coat single hollow guides with bore sizes as small as 250 um to the approximately 5O-~m-bore size guides which will make up the IR image bundle.The significance of this research lies in the anticipated reduction in loss for hollow glass guides by a factor of 10 or more through the deposition of multilayer dielectric coatings. The development of an efficient, coherent IR bundle for imaging beyond 2 ~m would mark the first time that such a high resolution, broadband bundle has been fabricated and, it is believed, this technology will have a major impact on thermal imaging systems used for recognition and process control. If we are successful in reducing the loss of the hollow guides by a factor of ten over current losses we will not only have a fiber well suited for thermal imaging but also a waveguide with significant potential in delivering laser power for surgical and other medical applications. In addition, our hollow bundle could be used in a transmit mode as well as in the receive mode. That is, it is possible to transniit laser energy for local heating and then to interrogate the resulting thermal energy via the same fiber bundle. Finally, it should be possible to make the ultimate smart fiber optic involving thermal imaging, power delivery, and chemical sensing all via the same hollow guide bundle.***