Warning: Missing argument 3 for write(), called in /www/wwwroot/biwei1.cn/incs/robot.php on line 68 and defined in /www/wwwroot/biwei1.cn/incs/data.php on line 487 Vein viewers use near-infrared light, which is absorbed by veins and reflected by surrounding tissue, to map veins up to 15mm deep and project the results onto the skin