非侵入式光學檢測技術在測量上具有不破壞待測物本身的優點，可保留樣本的完整性。隨著近年來健康意識抬頭，非侵入式的技術更是被廣泛應用於人體各項生理指數檢測。 漫反射光譜(DRS, diffuse reflectance spectroscopy)的量測為人體非侵入式光學檢測中常被使用的方式，藉光譜趨勢和強度的分析可獲得多項生理指數，如血紅素(Hb, hemoglobin)濃度、黑色素(melanin)濃度與有效散射粒子尺寸(scattering particle size)等，這些指數有助於了解受測者的身體狀態，甚至是疾病的診斷。 本研究以漫反射光譜量測系統，搭配主成分分析(PCA, principal component analysis)與類神經網路(neural network)，有別於只對光譜進行曲線擬合來觀察生理指數變化，本論文在一群經過高溫環境刺激與太陽曝曬的受試者手背皮膚的漫反射光譜中，經由PCA找出相關性較高的兩個主成分，以此為新的座標軸建構出二維空間，再以曲線擬合的方式取得此二維空間上不同的位置對應黑色素濃度、血紅素濃度與有效散射粒子尺寸的數值關係，完成後可藉由兩項主成分的投影量變化來觀察受試者的黑色素濃度、血紅素濃度與有效散射粒子尺寸的變化，最後再以類神經網路的方式以這兩項主成分的變化趨勢來對受試者的皮膚狀態進行判斷。本論文以高溫環境與太陽曝曬的刺激進行測試。完成後透過每週一次的量測即可得到受試者皮膚當下的三項生理指數變化，也可判斷是否受過高溫環境或是太陽曝曬的刺激，長期量測後可以每兩週的主成分變化量為一組進行類神經網路分析，可推論接受過太陽曝曬刺激後的受試者正處於第幾週的恢復期。;Non-invasive optical techniques have many advantages, for example, it will not damage a sample. It can also decrease the error during the measurement. With the awakening of health-conscious in recent years, non-invasive techniques are widely used in the detection of various physiological parameters in the human body. Diffuse reflectance spectroscopy is more often seen in non-invasive optical techniques. We are able to obtain some physiological parameters such as hemoglobin’s concentration, melanin’s concentration and scattering particle size by analyzing the trend and intensity of the spectrum. In this article, we set up a diffuse reflectance spectroscopy measurement which combines the PCA and the neural network. It is different from previous studies which always got the physiological parameters by curve fitting, but found out the reason additionally. The measurement in this article acquires the two most influential principal components from all the data at the beginning, and get hemoglobin’s concentration, melanin’s concentration and scattering particle size by curve fitting. Then, conclude whether the parameters change is caused by high temperature stimulating or getting tanned with the neural network. While the above-mentioned procedure is finished, we can determine not only what the environmental stimulating a person has undergone but also the recovery period of getting tanned directly by his/her diffuse reflectance spectroscopy. Through this measurement, we can observe both the difference between people and the physical condition of a person a period of time.
