過度日曬容易導致皮膚病變，嚴重的病變可能發展為皮膚癌而許多研究指出早期發現治癒機會極高。近年來許多研究證實生醫電阻抗相位和健康狀況相關聯，相位的研究多著重於全身電阻抗量測。然而大範圍人體電阻抗相位測量無法評估局部皮膚生理狀況，電阻抗相位變化亦十分細微且易受影響，故此研究主要以模擬的方式探討生醫電阻抗相位與皮膚病變的關係，以實際電阻抗量測流程分析電阻抗在不同皮膚厚度、電性參數、病變延展的結果，並試圖從結果中找出適合的量測方案。結果顯示低頻量測的相位解析度較好，易於評估健康皮膚深度與病變延展，且可避免病變區域與量測電極間幾何偏差所造成之相位誤差。

Excess sun exposure could cause skin lesion, or even worse, skin cancer. Early treatment helps to reduce mortality. Recently, studies shows the correlation between bioimpedance phase angle and health status, where vastly focus on total body measurement. Therefore, bioimpedance phase angle is adopted in skin lesion assessment with simulation. By simulating process of actual bioimpedance measurement, phase angle variation in different skin thickness, electrical parameter, lesion extension is evaluated. Finally, we try to introduce a proposal in measuring bioimpedance phase of skin lesion. The result shows a better phase resolution for low-frequency measurement. Low-frequency measurement is beneficial for estimating skin thickness and lesion extension, and provides good tolerance of phase error in lesion-electrode misalignment.

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