Ultra Thin Optical Fiberscope Using Phase Conjugate Wave

光纤内窥镜在医学诊断和无损测量中发挥了重要作用，并且近来图像特性得到了显著改善。光场的观测是基于光信息本身的传输而直接观测到的，因此光场的观测是必不可少的。但在传统的光纤光学系统中，图像分辨率受到光纤尺寸的限制，因为光纤束的每根光纤对应于这些系统中的一个图像像素。作为这种光纤束的替代方案，一种通过使用具有透镜状折射率变化的光纤直接传输图像的方法也已经被展示出来，但在这种情况下，只能使用直的和相对较短的光纤。另一方面，通过使用相位共轭，一种可能的新的光纤镜，它只需要一根多模光纤就可以实现物体场的重建。将光纤的输出端与光纤的输出端相耦合，产生所需的相位共轭波 ...更多信息 场通过相位共轭器;图像通过具有相同特性的单根光纤重新传输。因此，在该系统中，必须提供具有相同特性的一对光纤。然而，很难制造两个具有相同特性的光纤，为了避免这个问题，在本研究中，提出了将读写处理之间的时间共享合并到单个光纤中。这种方法导致放弃实时处理，对光纤的要求大大降低，由外来光引起的噪声被完全消除。演示示出了使用这种方案的小物体的实际观察。为此，所需的照明源通过将微透镜与第二光纤组装而制成，从而实现了尺寸为单个多模光纤直径的大约两倍的紧凑且非常薄的纤维镜。观测小物体的3-D场的结果产生系统的3-D分辨率。此外，还讨论了光纤弯曲对光纤传输的影响。显示了IC芯片的观察结果。少

Optical fiberscopes have played an important role in medical diagnosis and nondestructive measurements, and the image characteristics have recently been remarkably improved. The object is observed directly on the basis of transmission of the optical information itself, so it is essential for the observation of optical fields. But in conventional optical fiberscopest the image resolution is restricted by fiber size, because each fiber of the fiber bundle corresponds to an image Dixel in these systems. As an alternative to this fiber bundle, a method transmitting the image directly by using a fiber having a lenslike index variation has also been shown but in this case only straight and relatively short fiber can be used.On the other hand, by using phase conjugation a possible new fiberscope that achieves the reconstruction of the object's field with only a single multimode fiber is produced and demonstrated. The required phase conjugate wave can be generated by putting the fiber's output … More field through a Phase conjugator; the image is retransmitted through a single fiber with the same characteristics. Hence, in this system a pair of fibers with the same characteristics must be provided. However, it is difficult to fabricate two fibers with the same characteristics, and to avoid this problem in this research time sharing between read and write processing combined into a single fiber was proposed. This procedure leads to discarding real-time processing; the requirements on the fiber are greatly reduced and noise caused by extraneous light is eliminated completely.Demonstrations are shown of the actual observation of small objects using this scheme. For this purpose, the required source of illumination is made by assembling a microlens with a second fiber, thus a compact and very thin fiberscope having a size of about twice the diameter of a single multimode fiber is achieved. The results of observing a 3-D field of small objects yield the 3-D resolution of the system. In addition, the effects of fiber bending are also discussed. Results of observation of IC chips were shown. Less