| A beam of parallel light irradiates cylindrical fiber perpendicularly, the ray enters into the fiber and comes out by two refractions and one internal surface reflection, the farther the incident ray leaves the axes ray, the bigger the included angle exit ray opposite entrance ray by the fiber, when the ray reaches a position, the angle reaches the maximum. Later, the angle decreases again, the ray of the maximal included angle position is called the Descartes ray. The phenomenon is called the Descartes ray phenomenon.At present, researches on the reflecting performance of the retro-reflection fabric in the textile area are more, and the reporting on the reflecting performance of round-section fibers has too, but there isn't research on the special ray - Descartes ray, therefore, the dissertation do the coherent research on it. The idiographic aspects are as follows:First, the structure, performance, and the conditions accepting the light of little water drop which produces the Descartes ray in the rainbow phenomenon are analyzed, and build the fiber physical model; Second, in the variant light conditions, we analyze the fiber and get the production conditions, mechanics, and the influencing factors of the Descartes ray; Third, we design experiment principle drawing and produce the experiment device. The result of the theory analysis are tested and verified. We test and analyzed the interior reflected light, especially adjacent Descartes ray, and disclose the special optical property and regularity. Results of the research not only supplies a gist for the production of retro-reflective fabric , but also promotes reflecting property of similar structure ,luster of fiber and chemistry fiber plus material of garment and special reflecting fiber's development.At last, the dissertation makes the expectation about the development direction of the assignment. |
