Novel wavemeter on the basis of magnetic rotation effect

Abstract

The present invention provides a novel wavemeter on the basis of magnetic rotation effect mainly for measuring wavelength of pulse laser or continuous laser. The novel wavemeter is characterized in that the novel wavemeter is composed of a laser device to be detected, a collimator, a polarizer, a magneto-optical crystal, a permanent magnet, a polarization beam splitter, a temperature-control system, a balance photoelectric detector and a collecting and analyzing system. The laser to be detected enters into the polarizer, the magneto-optical crystal and the polarization beam splitter through the collimator orderly, and deflects with an angle corresponding to the wavelength in the polarization state of the laser to be detected of the magneto-optical crystal according to the magnetic rotation effect. Two laser beams emitted by the polarization beam splitter enters the balance photoelectric detector through a polarization maintaining fiber. The novel wavemeter on the basis of magnetic rotation effect is unique and novel in principle, does not require a mechanical movable part and a reference laser device in installation, and can measure pulsed laser. The novel wavemeter on the basis of magnetic rotation effect has good vibration resistance, small volume, and low cost. The novel wavemeter on the basis of magnetic rotation effect has simple laser path and good alignment by utilizing all-fiber.

Description

technical field [0001] The invention relates to a wavelength meter, in particular to a novel wavelength meter for real-time measurement of laser wavelength based on magneto-optical rotation effect. Background technique [0002] The wavelength meter is used to measure the laser wavelength. Some lasers, such as tunable lasers, can use their tuning mechanism to adjust the wavelength of their output light in a wide range of wavelengths. When semiconductor lasers change their operating temperature and driving current, their output The wavelength of light will change, and the output wavelength under suitable working conditions should be determined in advance when using it. Most lasers must also be re-calibrated for their output wavelength after delivery and maintenance. As the most benchmark value for measurement, laser wavelength is an important parameter for laser performance testing. It is widely used in the measurement of various physical parameters. It is an important measure...

AI Technical Summary

Problems solved by technology

The optical path passed by the reference light is consistent with the light to be measured, but due to the different wavelengths, the number of interference fringes is different. When the mirror moves a distance L, the number of fringes generated by the reference laser is The number of stripes produced by the laser to be tested In this way, the wavelength of light to be measured is obtained By introducing a reference laser, the measurement accuracy of the Michelson interferometric wavelength meter can reach 10 -6 -10 -9 , but there are still many deficiencies in terms of cost and scope of use: (1) the reference laser generally uses a single longitudinal mode He-Ne laser, which has high cost, limited life, and high maintenance cost; (2) Michelson interference wavelength The accuracy of the meter is affected by the collimation of the reference light and the optical path of the light to be measured. When the angle between the light to be measured and the reference light is too large due to vibration, temperature change or component aging, it will cause the stroke error of the two wavelengths, and finally lead to measurement errors. (3) Limited by the principle, the Michelson interferometer must move the mirror to produce the light and dark changes of the interference fringes, and the existence of mechanical moving parts limits the measurement speed (faster about 200HZ, about 5ms), At the moment when a laser pulse lasts, the prism is almost static, and the change of the interference fringe cannot be read, and the current technology level cannot measure narrow pulse light (ns order); (4) due to the large influence of temperature and vibration on mechanical parts , not suitable for use in workplaces with complex environments

However, these types of wavelength meters all need reference lasers, so they do not have advantages in terms of equipment volume, applicability in complex environments, and equipment and maintenance costs.

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