本實驗正交極化紅外光對手掌穴位的定位研究為主要探討，拍攝兩種TE(Transverse Electronic)和TM(Transverse Magnetic)偏振光源，利用邊緣檢測演算法維持圖像邊緣清晰性，再由100mA到500mA激發電流變化下轉換數值，為了強化灰度值的對比使用Pol(polarization)運算，且去除背景雜訊透過反遮罩(Unsharp Mask, USM)處理以凸顯高斯分布下灰度值的細節，最後利用平衡直方圖閾值法(Balanced histogram thresholding method, BHT)控制在0.2%灰度特徵分布面積，以完成蒙特卡羅方法(Monte Carlo method)的穴道分布狀態。
實驗的結果顯示，對於系統入射角為布魯斯特角(Brewster's angle)54.26度減少輸出光源的漫散射以及對應反射角為30度最穩定的訊號比，呈現穿透率(transmittance)為78%及反射率(reflectance)降至最低；當波長為700nm波段的激發電流在100mA到400mA電流區間和波長為800nm、900nm波段則是100mA到200mA電流區間藉由BHT測出多點特徵點。
當使用LED點光源時，光強度受到灰階落差影響容易邊緣失真影響，搭配輔助環形燈提高原先亮度1.5倍且提升照度均勻性。受到生物結構與組織對波長光譜反射影響，發現隨著波長增加、表面反射率降低，而達到電流變化下亮度變化的大小為穴位點的辨別，由反射光譜得知波段位於900nm最適合作為穴位定位偵測的依據，針對邊緣檢測索貝(Sobel Edge Detection)和高斯-拉普拉斯運邊緣演算法(Laplace of Gaussian Edge Detection, LOG)的覆蓋差異，得知使用Sobel時波長700nm對900nm的特徵分布覆蓋率為較LOG時波長700nm對900nm的特徵分布覆蓋率提高11%。

In this study, orthogonal polarized infrared light is used to locate the palm acupoints. Two kinds of TE and TM polarized images are taken, and edge detection algorithms are used to maintain image integrity. Then the excitation current changes from 100mA to 500mA with TE (Perpendicular) and TM (Parallel) convert the values, and calculate the Pol gray value contrast enhancement, through the anti-mask system (unsharp Mask, USM) processing to highlight the details of the Gaussian distribution of the gray value and achieve the removal of background noise, Finally, the balanced histogram thresholding method (BHT) is used to control the distribution area of the gray feature at 0.2%, and the acupoint distribution state of the Monte Carlo method is completed.
The results of the experiment show that the transmittance is 78% and the reflectance is the lowest due to reducing the diffuse reflection of the output light source at the angle of incidence of 54.26 degrees and the reflection angle of 30 degrees in the invisible light. The excitation current is in the range of 100mA to 400mA at 700nm, and the current range of 100mA to 200mA at the invisible light band, obtain multi-point characteristic values is measured at 800nm、900nm by BHT.
When using the LED point light source, the divergence is easily affected by the diffusive scattering of the surrounding light sources. With the auxiliary ring light, the original brightness is increased by 1.5 times and the illumination is uniform. Since the wavelength spectrum of reflection was affected by tissue structure and composition, it is found that the surface reflectance decreases, with, the wavelength increases and the difference brightness change of value is the acupuncture point. The wavelength of 900nm is most suitable as the basis for the detection of acupuncture points, and between Sobel Edge detection and Laplace of Gaussian Edge detection (LOG) image taken was compared with those of the Overlapping 900nm of 700nm. The 700nm overlapping 900nm that Overlapped rate of LOG higher than the Sobel is 11%.

[1]. N Dorababu, Y.K., K Venkatesu, "Electromagnetic Energy in Biological Tissues.". 2008.
[2]. Jacques, S.L., S. Roussel, and R. Samatham, Polarized light imaging specifies the anisotropy of light scattering in the superficial layer of a tissue. J Biomed Opt, 2016. 21(7): p. 71115.
[3] Busch, K., C.M. Soukoulis, and E.N. Economou, Transport and scattering mean free paths of classical waves. Phys Rev B Condens Matter, 1994. 50(1): p. 93-98.
[4] ZHOU Liang, YU Jiang-jun, LIU Zhao-hui, LI Zhi-guo, SHAN Qiu-sha, Simulation Study on Spectral Characteristics of Skin Tissue and Volume Pulse Wave in 400~1 000 nm Wavelength. 2020
[5]. Molar extinction coefficients of oxy and deoxyhemoglobin compiled by Scott Prahl." http://omlc.ogi.edu/spectra/hemoglobin"
[6]. Jim O' Doherty and Martin J. Leahy, Gert. E. Nilsson, "Polarized Light Spectroscopy for the Non-Invasive Investigation of Microvascular Red Blood Cell Proliferation in Dermal Tissue". 2006
[7]. R.L.P. van Veen, H.J.C.M. Sterenborg, A. Pifferi, A. Torricelli, and R. Cubeddu, OSA Annual BIOMED Topical Meeting, 2004
[8] 醫砭, 中華針灸 體表標誌定穴法" http://yibian.hopto.org/shu/?sid=7019."
[9] A+醫學百科 國際標準經穴位表" http://cht.a-hospital.com/w/%E4%B8%AD%E5%8D%8E%E4%BA%BA%E6%B0%91%E5%85%B1%E5%92%8C%E5%9B%BD%E5%9B%BD%E5%AE%B6%E6%A0%87%E5%87%86%C2%B7%E7%BB%8F%E7%A9%B4%E9%83%A8%E4%BD%8D
[10] Lambert, Johann Heinrich. "Photometria, sive de mensura et gradibus luminis, colorum et umbrae."
[11]. Manish Bhatt, Kaylan R. Ayyalasomayajula, Phaneendra K. Yalavarthy, "Generalized Beer–Lambert model for near-infrared light propagation in thick biological tissues.". 2016.
[12] Jian Jim Wang, Frank Walters, Xiaorming Liu, Paul Sciortino, Xuegong Deng"High-performance, large area, deep ultraviolet to infrared polarizers based on 40 nm line/78 nm space nanowire grid" 2007.
[13]. Asahi Kasei Wire Grid Polarizer Film WGF, "https://www.asahi-kasei.co.jp/ake-mate/wgf/en/product/index.html"
[14]. Jim O’Doherty, M.J.L., Gert. E. Nilsson, Joakim Henricson, and Folke Sjöberg, "Polarized Light Spectroscopy for the Non-Invasive Investigation of Microvascular Red Blood Cell Proliferation in Dermal Tissue.". 2006.
[15] 穴道經絡庫" https://m.keaitupianku.com/kea/手腕穴位图解大全/"
[16] 鍾會清，郭周義，魏華江，倪藝榕 and 熊紅蓮，金梅，吳秀麗，劉智明, "光學取穴儀器". 2014.
[17] Jing, Z.J.Z.Y.H.B., "基于梯度优化法的连续波近红外光断层成像研究.". 2004.
[18]. 趙惠娟，王志朝，王婷婷，侯少華，高峰, "基于数字锁相解复用的多通道近红外光并行检测技术." 2011.
[19]. D.C. Marr and E.Hildreth, "Theory of Edge Detection," in Proc. Int. Roy. Soc. London, Vol. B275, pp.187-217, 1980.
[20]. Jacques, S.L., J.C. Ramella-Roman, and K. Lee, Imaging skin pathology with polarized light. J Biomed Opt, 2002. 7(3): p. 329-40.
[21]. G. Kós, "Recovering Variable Radius Rolling Ball Blends in Reverse Engineering." 2000.
[22] 何莉, "头颈部危险穴位测量与定位方法研究.". 2011.
[23]. 相機曝光補償"https://snapshot.canon-asia.com/taiwan/article/zh/camera-basics-4-exposure-compensation"
[24]. Huynh-Thu, Q.; Ghanbari, M. "Scope of validity of PSNR in image/video quality assessment". Electronics Letters. 2008.
[25]. Kuz’min, Vladimir, Neidrauer Michael, Diaz David, Zubkov Leonid, "Diffuse photon density wave measurements in comparison with the Monte Carlo simulations". 2015.
[26]. 曹鴻，宋連科, "偏振光入射方位角與介質反射率關係研究.". 2004.
[27]. van Zijderveld, R., C. Ince, and R.O. Schlingemann, Orthogonal polarization spectral imaging of conjunctival microcirculation. Graefes Arch Clin Exp Ophthalmol, 2014. 252(5): p. 773-9.
[28]. Steven L. Jacques PhD, J.R.R.M., Ken Lee MD, "Imaging Superficial Tissues With Polarized Light.". 2000.