An oxygen sensor for a wearable electronic device includes a first light source, a second light source and a light sensor. The first light source, the second light source and the light sensor are disposed in the wearable electronic device. The second light source is disposed close to the first light source. The light sensor is disposed away from the first and second light sources. The first light source emits light in the wavelength range between 600-800 nm, and the second light source emits light in the wavelength range between 800-880 nm.一種血氧感測器適用於穿戴式電子裝置,血氧感測器包含第一光源、第二光源以及光感測器,第一光源、第二光源與光感測器設置於穿戴式電子裝置。第二光源緊鄰第一光源,光感測器與第一、第二光源係分離設置。第一光源發出波長範圍在600-800奈米之間的光線,第二光源發出波長範圍在800-880奈米之間的光線。10‧‧‧穿戴式電子裝置100‧‧‧本體110‧‧‧血氧感測器111‧‧‧第一光源112‧‧‧第二光源113‧‧‧光感測器115‧‧‧控制電路
