The Fourier transform power spectrum of input object can be obtained when the input image is placed at the front or back of the hololens.

将输入图像置于这种全息透镜的前面或后面，均能得到物体的傅里叶变换功率谱。

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The OTF (Optical Transfer Function) of an optical system can be evaluated by the Fourier Transform of the first derivative of the optical image of an knife-edge (object).

对光学系统输出刀口像的一阶导数做傅里叶变换，可以得到该系统的光学传递函数（OTF）。

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The method defines different member function for the object and background of the image to transform the image into fuzzy domain with maximum fuzzy entropy.

该方法将图像分为目标和背景，并分别建立相应的模糊隶属函数来描述图像各个灰度级属于目标和背景的模糊特性，进而给出图像模糊熵的描述。

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