Optical component weak absorption test device and method based on equivalent temperature

Abstract

The invention provides an optical component weak absorption test device and method based on the equivalent temperature. The method is characterized in that firstly, a sample is irradiated with pump laser, after a steady state is realized, the highest temperature of the sample surface is recorded through utilizing an infrared thermal imager, and reflection and transmission powers of the sample aretested through utilizing a pump light power meter; secondly, a probing laser is utilized to (a CO2 laser, the spot size is the same as that of the pump laser spot) irradiate the surface of the sample,generally, an absorption rate of CO2 for an optical element such as a dielectric film is 1, the probing laser power is increased gradually to make the surface temperature of the sample reach the temperature of a first test, at this time, the power in a probing light power meter is read; and lastly, the sum of ratios of the reading of the probing light power meter to the reflection and transmission powers of the sample is the weak absorption rate of the sample surface. The method is advantaged in that the absorption rate of the CO2 laser is mainly 1 through utilizing a general optical element,the temperature characteristics of the sample under pump light irradiation are utilized to test the weak absorption rate of the surface, compared with technical tests in the prior art, not only precision is high, but also operation is simpler and more convenient, and no post-data processing is required.

Description

technical field [0001] The invention belongs to the field of testing the absorptivity of optical components, in particular to a device and method for testing weak absorption of optical components based on equivalent temperature. Background technique [0002] With the continuous improvement of laser power, the quality requirements of laser thin films and various optical components are getting higher and higher. Under strong laser irradiation, the weak absorption of optical components will cause damage to the surface of optical components. Therefore, it is necessary to detect the average absorption rate of optical thin films accurately, quickly and in real time, so as to provide an important theoretical basis for the reduction of absorption loss, the improvement of damage threshold and the high-quality preparation of optical thin films. [0003] The testing techniques for the absorptivity of optical films mainly include: photothermal radiation technology, laser calorimetry tec...

AI Technical Summary

Problems solved by technology

Both transmission photothermal deflection technology and thermal lens technology cannot test the absorption of opaque materials, and the absorption rate is the result of indirect testing. The intermediate data processing link has strong random errors, resulting in limited testing accuracy.

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