Nonlinear optical Fourier filtering technique for medical image processing.
Nonlinear optical Fourier filtering technique for medical image processing.
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用于医学图像处理的非线性光学傅立叶滤波技术。
DOI：
10.1117/1.1953287
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发表时间：
2005
影响因子：
3.5
通讯作者：
Rao,DVGLN
中科院分区：
文献类型：
--
作者：
Kothapalli,Sri-Rajasekhar;Wu,Pengfei;Yelleswarapu,ChandraS;Rao,DVGLN
利用生物光子材料细菌视紫红质(BR)薄膜的光调制特性，提出了一种用于医学图像处理的实时非线性光学傅立叶滤波方法。实验研究了BR膜在442 nm探测光束和568 nm控制光束作用下的非线性传输特性。通过改变黄色控制光束的位置和强度，在BR膜中选择性地操纵由蓝色探测光束携带的空间频率信息。该技术的可行性首先通过不同形状和大小的幻影对象来确定。该技术被应用于滤除与柔软致密的乳房组织相对应的低空间频率，并且在临床屏幕胶片乳房X光照片中仅显示与微钙化相对应的高空间频率。在电寻址空间光调制器(SLM)的帮助下，我们成功地将该技术应用于数字体模和数字乳房X光照片的处理。与使用面具的传统光学空间过滤技术不同，所提出的技术可以很容易地适应乳房X光照片中细节的大小和形状的变化。
Real-time nonlinear optical Fourier filtering for medical image processing is demonstrated, exploiting light modulating characteristics of thin films of the biophotonic material bacteriorhodopsin (bR). The nonlinear transmission of bR films for a 442 nm probe beam with a 568 nm control beam and vice versa is experimentally studied in detail. The spatial frequency information carried by the blue probe beam is selectively manipulated in the bR film by changing the position and intensity of the yellow control beam. The feasibility of the technique is first established with different shapes and sizes of phantom objects. The technique is applied to filter out low spatial frequencies corresponding to soft dense breast tissue and displaying only high spatial frequencies corresponding to microcalcifications in clinical screen film mammograms. With the aid of an electrically addressed spatial light modulator (SLM), we successfully adapt the technique for processing digital phantoms and digital mammograms. Unlike conventional optical spatial filtering techniques that use masks, the technique proposed can easily accommodate the changes in size and shape of details in a mammogram.