网站地图
光源面分布对激光针灸经穴组织的漫反射影响
Diffuse reflection on the acupuncture point under laser acupuncture with different spatial distribution
-
摘要: 为了研究光源面分布对激光针灸经穴组织的漫反射传输影响,利用激光针炙在穴位组织中虚拟点源的镜像点源分布函数、并引入格林响应函数,外推边界条件求解得到点光源的漫射方程解,由人体穴位4层介质组织的一系列虚拟点源的响应得到不同空间分布光源下人体穴位的激光针炙漫反射模型;采用蒙特卡罗方法模拟了圆平面、光纤及高斯分布的面光源激光针灸。结果表明,无光斑时3种光源的径向光能主要集中在近激光针灸点区域,径向距离大于0.135cm,3种光源卷积曲线重合,圆平面和高斯光源的轴向光能呈负指数衰减,光纤光源呈直线下降;存在光斑时面光源的漫反射与光斑面积成反比,等光斑面积下圆屏光斑比圆环光斑的组织漫反射大,光斑垂直投影处漫反射曲线存在明显畸变,投影外畸变与距离成反比,达到0.5个光斑半径距离时畸变基本消除。该结果可为穴位针灸的光源选取与针灸定位提供有益参考。Abstract: In order to study the diffuse transmission influence of laser acupuncture with different surface distribution light sources,the image-point-source distribution on meridian tissue is analyzed and diffusion equation of the image-point-source is solved through the use of extrapolation boundary conditions and Green response.Diffuse output models in acupuncture region for different distribution surface light source are obtained by a series responses of virtual points source.Flat,fiber and gauss acupuncture laser are simulated by Monte-Carlo method.The results indicated that; (1) the radial light energy in three acupuncture without spot mainly was concentrated in the near light source region and coincided when the radial distance to more than 0.135 cm,and axial light energy showed a negative exponential decay in flat and gauss acupuncture and linear decline in fiber source; (2) when surface light source existed circular or ring spot,the diffuse was inversely proportional to the spot area, especially the diffuse of circular spot being larger than the ring spot under the same spot area,and diffuse reflectance curve had a significant distortion at the vertical projection and was inversely proportional to the distance outside the projection,especially when the distance to 0.5 times of the spot radius the curve distortion being basically eliminated.The results may provide a useful reference for light source selection and acupuncture location of acupuncture points.
-
[1] WHfITAKER P.Laser acupuncture:past,present,and future[J].Lasers in Medical Science,2004,19(2):69-80. [2] JOHNG H M,CHO J H,SHIN H S,et al.Frequency dependence of impedancea at the acupuncture point Quze(PC3)[J],IEEE Engineering in Medicine and Biology,2002,21(2):33-36. [3] CHOI C,SOH K S.Study of propagation of light along an acupuncture meridian[J].Journal of the Optical Society of Korea,2003,7(6):244-247(in Korcan). [4] McNALLY K M,SORG B S,WELCH A J,et al.Photothermal effects of laser tiasue soldering[J].Physics in Medicine & Biology,1999,44(4):983-1002. [5] WANG X C,GONG Y J,SONC D C,et al.The spatially resolved scattered reflection of three layered matched media diffusion equation in the steady-state[J].Acta Photonica Sinica,2005,25(3):377-381 (in Chineae). [6] KIENLE A,PATTERSON M S.Impmved solutions of the iteady-state and the time-resolved diffusion equations for reflectance from a senuinfinite turbid medium[J].Journal of the Optical Society of America,1997,A14(1):246-254. [7] LAI J Ch,LI Zh H,WANG Zh D,et al.System model oflidt transporting in biological tiasues and its application[J].Acta Photonica Sinica,2007,36(7):1312-1317 (in Chineae). [8] WANC Sh,RUAN J,HE Q L.Study on photo-damage selectivity in photodynamic therapy by means of Monte Carlo method[J].Laser Technology,2008,32(2):184-186 (in Chinese). [9] WEI P F,ZHAO Y Q,UANG Y,et al.Monte Carlo simulations of polarized light transport in multilayered scattering media[J].Acta Photonica Sinica,2009,38(10):2634-2639 (in Chinese). [10] LI Zh H,LAIJ Ch,WANG Zh D,et al.The application of impulseresponse function in Monte Cado simulation of light distribution in biological tiasues[J].Ltser Technology,2001,25 (4):263-268(in Chinese). [11] DOOMBOS R M P,LANG R,ALDERS M C,et al.The determination of in vivo human tissue optical properties and absolute chromophore concentrat ions using spatially resolved steady-suue diffuse reflectance spectroscopy[J].Physics in Medicine and Biology,1999,44(3):967-981. -
点击查看大图
计量
- 文章访问数: 3625
- HTML全文浏览量: 590
- PDF下载量: 671
- 被引次数: 0
下载:
