空載光達的雷射可穿越樹冠層的遮蔽到達地表面，對於面積較大之森林區域，可在短時間獲得大量點雲的反射強度值（Intensity）以及三維坐標。點雲資料包含地面點以及地物點，可用於森林地區製作DEM （Digital Elevation Model)。而雷射的穿透率會受到地表覆蓋物、航高以及雷射入射角的影響。本研究樣區分別為南仁山生態保護區以及那瑪夏區達卡努瓦里，兩樣區皆有大量森林覆蓋。三種空載光達（Optech Pegasus HD400、Leica ALS60、Riegl LMS-Q680i）收集資料於同一樣區的低、中及高航高的資料分別計算地面穿透率，由實驗結果可以得出Optech HD400與Riegl LMS-Q680i於低航高2000 m及1250 m的穿透率與中航高及高航高相比，穿透率大於0.2的次數較多；Leica ALS60在不同航高的穿透率則無顯著差異。同一地區不同空載光達的穿透率為Optech HD400於南仁山的穿透率最佳；Leica ALS60於達卡努瓦里穿透率最低。由研究成果，穿透率的成果與光達的參數設定及其飛航資料有關。

Airborne LiDAR can obtain abundant 3D coordinates and intensity of point clouds which include ground points and object points in short time by penetrating the canopies to the ground in forest areas which can be used in making DEM (Digital Elevation Model). The coverage on the topography, flying height and laser incident angle have an effect on the laser penetration of the LiDAR. Three different types of airborne LiDAR (Optech HD400, Leica ALS60 & Riegl LMS-Q680i) separately collect data in low, medium and high flying altitude in the same area to calculate the ground penetration where plenteous tree species cover two study areas: Najenshan ecological reserve area and Dakanuwa village, Namaxia district, Kaohsiung City. To sum up from the research, the number of penetration rate greater than 0.2 in low flying altitude, 2000 m for Optech HD400 and 1250 m for Riegl LMS-Q680i respectively, are much more than medium and high flying height in contrast that Leica ALS60 has no significant discrepancy. Besides the effect of flying altitude, the setting of LiDAR’s parameters result the better penetration for Optech HD400 in Najenshan ecological reserve area and worse to Leica ALS60 in Dakanuwa village.