Optical Computed Tomography by Detection of Photons Preserving initial Polarization Through a Scattering Medium

通过检测通过散射介质保持初始偏振的光子进行光学计算机断层扫描

基本信息

批准号：
09555016
负责人：
HORINAKA Hiromichi
金额：
$ 4.67万
依托单位：
Osaka Prefecture University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

An optical CT apparatus using photons preserving initial polarization was designed on the basis of results of fundamental experiments. A diode laser, a phase-modulator, a translation stages and a detector were mounted on a small optical bread board. A personal computer was used for three purposes; control of translation stages and the gain of the lock-in amplifier, acquisition of the projection data and reconstruction of the optical CT image. The apparatus had the ability to suppress the diffused light in the transmitted light up upto 110dB.The following applications of the optical CT apparatus were investigated.(1) Two dimensional distribution of fruits ingredientsOur optical CT apparatus was applied to a pimento and a summer orange and their optical CT images were reconstructed from projection data. The internal section and the core were able to be recognized, although the spatial resolution of images was not sufficient. Three diode lasers, which had different emission wavelengths in … More dividually corresponding to the absorption lines of water, sugar (sucrose) and chlorophyll A were employed to take the projection data of the fruit. Two dimensional distribution of absorption coefficient of the reconstructed images depended on the wavelength of laser. It means the possibility that two dimensional distribution of every ingredient in food is obtained by our apparatus.(2) Detection of foreign matter in foodX ray is applicable to the detection of metals in food, but is not effective for pieces of plastics. Our apparatus was applied to detection of foreign matter in food. The projection data of the milk in a bottle in which a piece of plastic was set as a foreign matter. The existence of a piece of plastic was clearly recognized in the reconstructed image. The image by our method is easily influenced by the change of refractive index, which is common problem in the methods detecting photons travelling near the straight line. The sensitivity of our method to the boundary of refractive indices is also expected to be used for the detection of foreign matter in food. Less

基于基本实验的结果，将光学的CT固定器安装在基本实验的基础上。放大器，项目的采集和光学法师的重新构造。 CT图像是从投影数据中重建的。 a被用来取下果实的投影将塑料设置为异物的瓶子中的牛奶在图像中清楚地识别出塑料的存在很容易受到裂纹指数的变化的影响，这在方法检测光子附近传播的方法中很常见海峡线。