Device and method for measuring relative intensity noise of laser

Abstract

The invention discloses a device and method for measuring relative intensity noise of a laser. According to the method for measuring the relative intensity noise of the laser, the principle that after a single frequency point electric signal passes through a microwave photon link, a phase-noise index is correspondingly deteriorated is adopted and the relative intensity noise of the laser in the link is calculated through the change quantity of phase noise. The basic structure of the device for measuring the relative intensity noise of the laser comprises a single frequency point signal resource, a microwave photon link, an optical power meter and a phase-noise detector, wherein the microwave photon link is mainly composed of the laser, an electro-optical modulator, an optical coupler and a photoelectric defector. Compared with a traditional measuring method, the method for measuring the relative intensity noise of the laser has the advantages that the measuring process is conducted on the high-frequency end of an electricity domain, influence caused by various environment noises near the direct current end is avoided, the measuring accuracy is improved, the output power of the laser to be detected does not need to be considered according to the scheme, and the limitation, caused by optical output power, of a measuring system in the traditional measuring method is overcome.

Description

technical field [0001] The invention belongs to the field of electronic measurement, in particular to a measuring device and method for the relative intensity noise of a laser. Background technique [0002] Optoelectronic technology is an important part of contemporary high-tech, and plays a pivotal role in national economy and national defense construction. With the rapid development of optoelectronic technology, lasers, as an important optoelectronic component, have been widely used in many fields such as optical communication, information storage, medical treatment, and optical sensing. In the fields of optical storage and optical communication, the relative intensity noise (Relative Intensity Noise, hereinafter referred to as RIN) of the laser is one of the important parameters to determine the performance index of the system. The RIN of the laser will affect the signal-to-noise ratio and sensitivity of the communication system. [0003] The relative intensity noise of ...

AI Technical Summary

Problems solved by technology

The traditional solution needs to directly inject the output optical power of the laser into the photodetector. When the output optical power is large, it will obviously exceed the saturated input optical power of the detector, resulting in errors in the conversion of electro-optical noise, and may even exceed the detector’s maximum Input optical power, causing damage to the detector

[0013]2. Near DC noise is relatively large, which affects RIN measurement accuracy

For electronic devices, the frequency spectrum near the DC side is very rich and subject to external interference. These additional noises will be parasitic into the frequency spectrum of RIN through the photodetector and electric amplifier, reducing the measurement accuracy

[0014] Based on the above analysis, it can be seen that the measurement accuracy of the current measurement scheme for the laser RIN is not high and the limitations are relatively large. How to accurately measure the RIN of the laser An important bottleneck in fields such as photonics

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