Figure 1 is a schematic diagram of the principle of fiber optic image bundles. When in use, the target is imaged on the end face of the image beam through an optical objective, and the image on this end face can be seen as composed of many pixels with varying brightness. Each fiber has good optical insulation performance, that is, its independent transmission surface is not affected by neighboring fibers. Therefore, the optical fiber's transmission surface (i.e. the fiber core layer) can be regarded as a sampling hole, carrying a pixel in an independent transmission process. The size of the pixel is the size of the sampling hole, and the number of pixels is equal to the number of optical fibers on the end face. The two ends of the image beam must be arranged in a correlated and one-to-one correspondence, which means that the geometric positions of each fiber on the incident and outgoing ends of the image beam must be completely consistent. Therefore, the outgoing image and the incident image are basically consistent. When there is a certain distribution of light energy (i.e. image) on one end face of the image beam, a mirror image of the image is generated at the other end of the image beam. The two ends of the fiber optic image bundle need to be glued together, and the middle part can be loose, so images can be transmitted along a curved path, which is difficult for ordinary optical systems to achieve. However, fiber optic image bundles require strict related arrangements and extremely high wire density, which creates a dual challenge of high manufacturing technology difficulty and high cost, especially in the manufacturing of large-section fiber optic image bundles. Due to the limitations of manufacturing process difficulty, the yield of producing high-quality large-section fiber optic image bundles is relatively low. Especially the broken wires, dark wires, misalignment, and uneven stacking formed during the production process have a significant impact on the quality of transmitted images. In addition, due to the limitations of the image transmission mechanism of fiber optic image bundles, a grid structure of fiber optic image bundles is added to the background of the output image, which also leads to a decrease in image quality. So, currently, many applications use wavelength division multiplexing technology to improve image quality, in order to compensate for the defect of reduced image quality.
Excerpt from an article on Zizhiwang titled "Fiber optic Image Beams in Optical Systems"
