Well-logging Imaging Research And Application Based On Self-mixing Interference Of Laser

In the detection of the oil industry, it is always encountered some problems.In some environments which need to be detected, because of the high risk and the limitation, the detection personnel can not detect the fault point in person in person, not only caused the loss,but also greatly increased the danger because of the time delay.In the use of some conventional equipment for fault detection, due to technical limitations, it is difficult to obtain satisfactory results, which will cause the detection of false positives and reported errors.Through the comparison of technical characteristics, in numerous imaging technology,laser self mixing interference technology come to the fore, it has simple equipment, low cost,high detection accuracy and good real-time many advantages and compared to the traditional optical imaging technology, laser self mixing interference technology can obtain a higher level of depth perception, which is more close to biological description of objects, more conducive to the point of failure information acquisition. Based on laser self mixing interference technology for underground detection technology research, improvement and application, for in recent years, the increasing demand for well-logging imaging is undoubtedly new and stronger power.Laser self-mixing interference excavation began in laser optical feedback research. Laser self-mixing interference is refers to the semiconductor laser light emitting diodes emitted from the light, through external vibration objects reflected back to the laser cavity, between the two beams coupling and the output power of the laser internal packing of photo diode has changed. Through the research of the photo diode output power and feedback rules between the light, the formation of the laser self mixing interference theory and the technology is widely used in distance, displacement, vibration, speed and other parameters measurement.In this paper, the basic theory of laser self mixing interference technique and its application in distance measurement are described in detail,and the general model of laser self mixing interference theory is studied.The model of self mixing interference in weak optical feedback is analyzed.At the same time, because the light path is simple, easy to be aligned,compact structure and so on,the application of self mixing interference effect in distance measurement is proposed.On this basis,develop the single light source vibration sensor based on Laser self-mixing interference technique,and as far as possible to make it applicable to the underground detection environment.