Study On Optical Sensing Properties Of Spider Silk

Researchers have found many natural biomaterials in nature,they exhibit a more excellent structure and characteristics compared with traditional composite materials,and can be directly derived from the environment as a renewable resource.As a new biological material,spider silk has a high potential application value.They not only have good mechanical properties,but also have unique biocompatibility,bio-absorbability and ecological friendliness due to their natural advantages.Nowadays,the research of spider silk is mainly in its mechanical properties,and its optical properties and its application in the field of optics are very little.In this paper,the optical properties of spider silk as optical fiber and its sensing properties as optical devices are mainly studied.Using the near-field evanescent wave coupling method,the light is coupled to the spider silk,and the transmission loss of the spider silk is measured by measuring the scattering loss method.The index of refraction of spider silk was measured by the method of infiltration image analysis.Relatively thin spider silk,such as dragline(diameter of 1~5?m),has the properties of transmission light similar to micro nano-fiber.It is used as material for making spider wire sensor based on interference structure.Make a made of dragline silk Araneus Ventricosus spider's sensor based on the structure of spider silk.The structure of Maher Zehnder interferometer,and its sensing properties were studied.Spider silk Maher Zehnder respectively.The optical micro cavity temperature sensing properties have been studied and its sensing properties: interference spectrum blue shift with increasing temperature,the highest sensitivity of 5.0nm/ ?.The echo wall optical resonator is widely used in the field of laser and sensing technology.However,the fabrication technology of optical resonator used in various fields is very complex,and many materials are made of ecofriendly,non-degradable and even toxic materials.Now we are from the nature to find a biocompatible Araneus Ventricosus spider egg case silk directly as a whispering gallery mode optical micro cavity,which has very sensitive sensing characteristics,sensitivity to humidity are beyond many of the traditional sensor,do the spider silk(a kind of ecofriendly materials)the real application in the optical field.The optical micro-cavity based on the Spider Egg filament whispering gallery mode can reach 570pm%RH at the relative humidity 21%-55%,and the sensitivity is 1130pm/%RH at relative humidity 65%-96%.The sensing principle of the optical micro-cavity of the spider silk echo wall model was studied from the humidity expansion coefficient of the spider's egg wire and the moisture optical coefficient of the spider.A large number of statistical methods were used to measure the relationship between the diameter of the spider silk and the moderation.The relationship between the refractive index of the eggs and the humidity was measured by simulation and experimental calculation.Finally,the wet expansion coefficient and the wet light coefficient of the spider egg silk were measured and verified.In this paper,we studied the optical sensing characteristics of spider silk,and proposed two kinds of sensors based on spider silk as an optical device,and further studied the sensing principle.