论文部分内容阅读
提出一种对光源输出功率稳定度要求相对较低的激光全息防伪产品光学特性参数检测方法。使用一块透反比一定的玻璃基片,将相对不稳定度3%的 He-Ne 激光器输出光束分为两束:反射光和透射光。两束光光强度比例恒定,测量反射光强计算出透射光强度。透射光作为再现光照明激光全息防伪标识,其衍射光构成物体再现像。实时探测标识光栅处以及无光栅处的衍射光强与反射光强,进而得到光栅处衍射光强与再现光强的比值及其与无光栅处衍射光强的比值,即全息防伪标识的衍射效率和信噪比。实验结果表明:透射光强测量值相对误差不超过0.2%;衍射效率及信噪比的测量值相对误差分别不超过0.8%和1.9%。
A new method to measure the optical parameters of laser holographic anti-counterfeit products with relatively low stability of light source output power is proposed. Using a glass substrate with a certain inverse transmittance ratio, a He-Ne laser output beam with a relative instability of 3% is split into two beams: reflected light and transmitted light. The ratio of the two light intensity is constant, and the transmitted light intensity is calculated by measuring the reflected light intensity. The transmitted light illuminates the laser holographic anti-counterfeit mark as the reproduction light, and the diffracted light constitutes the reproduced image of the object. Real-time detection of the grating and the grating at the diffraction of light intensity and intensity of the reflected light, and then get the ratio of diffraction grating light intensity and intensity of reproduction and diffraction ratio of light diffraction grating with no grating at the diffraction efficiency of the logo And signal to noise ratio. The experimental results show that the relative error of the transmitted light intensity measurement does not exceed 0.2%, and the relative errors of the diffraction efficiency and the signal to noise ratio measurement do not exceed 0.8% and 1.9% respectively.