菲涅尔镜片又称螺纹透镜，镜面上刻录了大小不一的螺纹。上一代主流会采用菲涅尔镜片因为这样透镜更薄更轻，厚度很薄，通常只有几毫米，重量也大大减轻。使用螺纹镜片会有一定的牺牲，因为螺纹会影响曲率和光线聚焦。 Now, that explained: becoming a cheap bastard and loving applied electronics, I've had negative luck with Refurbished stuff normally. Refurbished to me commonly suggests it had been beat... https://coingenius.news/ethereum-network-stronger-than-ever-as-defi-usdt_eth-grow/