Laser self-mixing interference（SMI） wave plate measurement method is a burgeoning technique for its simplicity and efficiency. But for the non-coated sample, the reflected light from the surface can seriously affect...Laser self-mixing interference（SMI） wave plate measurement method is a burgeoning technique for its simplicity and efficiency. But for the non-coated sample, the reflected light from the surface can seriously affect the measurement results.To analyze the reason theoretically, a self-consistent model for laser operation with a sub-external and an external cavity is established, and the sub-external cavity formed by the sample and a cavity mirror is proved to be the main error source.A synchronous tuning method is proposed to eliminate the sub-external cavity effect. Experiments are carried out on the synchronously tuning double external cavities self-mixing interference system, and the error of the system is in the range of -0.435°~0.387° compared with the ellipsometer. The research plays an important role in improving the performance and enlarging the application range of the laser self-mixing interference system.展开更多
A measuring method of surface mobility for an infinite plate subject to a uniform conphase velocity excitation is investigated. In the measurement, a finite plate is employed to simulate an infinite plate and a rigid ...A measuring method of surface mobility for an infinite plate subject to a uniform conphase velocity excitation is investigated. In the measurement, a finite plate is employed to simulate an infinite plate and a rigid cone is used to make a uniform conphase velocity excitation. A method to deduct the affect of additional mass is derived. The results of the measurement agree with that calculated theoretically.展开更多
Multilayer transparent plates play a crucial role in industrial fields,such as optical lenses,electrodes,and solar panels,because of their superior optical and electrical properties.The thickness and uniformity of suc...Multilayer transparent plates play a crucial role in industrial fields,such as optical lenses,electrodes,and solar panels,because of their superior optical and electrical properties.The thickness and uniformity of such plates are decisive for the quality of the final product.However,traditional contact measurement methods are inadequate in accuracy and pose the risk of damaging the plates,making nondestructive measurement of multilayer transparent plate thickness rather challenging.A new measurement technology is urgently needed.This study proposes a new method for the thickness measurement of multilayer transparent plates based on chromatic confocal sensor technology.First,we investigated the dispersive behavior of light in various media layers and derived theoretical measurement models for single-layer and multilayer transparent plate thicknesses.Subsequently,we designed and constructed a measurement system using a C-series chromatic confocal sensor and optical instruments and prepared a five-layer transparent sample consisting of quartz and air layers to confirm the feasibility of the method.The results of the experiment show that the proposed method can accurately measure the thickness of the five-layer sample with a maximum absolute error within 13μm and a maximum relative error of 4.27%,thus proving its validity,precision,and stability.The results further indicate the high practicality and reliability of this technology in production environments,theoretically enabling the simultaneous measurement of up to 18 layers of the plate and offering broad application prospects in the industry.展开更多
文摘Laser self-mixing interference（SMI） wave plate measurement method is a burgeoning technique for its simplicity and efficiency. But for the non-coated sample, the reflected light from the surface can seriously affect the measurement results.To analyze the reason theoretically, a self-consistent model for laser operation with a sub-external and an external cavity is established, and the sub-external cavity formed by the sample and a cavity mirror is proved to be the main error source.A synchronous tuning method is proposed to eliminate the sub-external cavity effect. Experiments are carried out on the synchronously tuning double external cavities self-mixing interference system, and the error of the system is in the range of -0.435°~0.387° compared with the ellipsometer. The research plays an important role in improving the performance and enlarging the application range of the laser self-mixing interference system.
文摘A measuring method of surface mobility for an infinite plate subject to a uniform conphase velocity excitation is investigated. In the measurement, a finite plate is employed to simulate an infinite plate and a rigid cone is used to make a uniform conphase velocity excitation. A method to deduct the affect of additional mass is derived. The results of the measurement agree with that calculated theoretically.
基金supported by National Natural Science Foundation of Zhejiang Province(No.LDT23E05012E05)National Natural Science Foundation of China(Grant No.52175439)+1 种基金National Key R&D Program of China(No.2021YFB3400300)the Fundamental Research Funds for the Central Universities(No.2023QZJH10).
文摘Multilayer transparent plates play a crucial role in industrial fields,such as optical lenses,electrodes,and solar panels,because of their superior optical and electrical properties.The thickness and uniformity of such plates are decisive for the quality of the final product.However,traditional contact measurement methods are inadequate in accuracy and pose the risk of damaging the plates,making nondestructive measurement of multilayer transparent plate thickness rather challenging.A new measurement technology is urgently needed.This study proposes a new method for the thickness measurement of multilayer transparent plates based on chromatic confocal sensor technology.First,we investigated the dispersive behavior of light in various media layers and derived theoretical measurement models for single-layer and multilayer transparent plate thicknesses.Subsequently,we designed and constructed a measurement system using a C-series chromatic confocal sensor and optical instruments and prepared a five-layer transparent sample consisting of quartz and air layers to confirm the feasibility of the method.The results of the experiment show that the proposed method can accurately measure the thickness of the five-layer sample with a maximum absolute error within 13μm and a maximum relative error of 4.27%,thus proving its validity,precision,and stability.The results further indicate the high practicality and reliability of this technology in production environments,theoretically enabling the simultaneous measurement of up to 18 layers of the plate and offering broad application prospects in the industry.
