The 360 ° inner wall surround view detection lens is applied to capture the bottom of the inner hole and its vertical inner wall. It can detect the inside from the outside without placing the lens inside the hole. Thanks to its large viewing angle (82 °) and innovative optical design, this lens has a large depth of field and can clearly image both the top and bottom of the object at the same time. The larger the diameter of the measured object, the higher the height that can be measured. The diameter of the measured object that can be photographed is 5mm-120mm, and the measurement height is 5mm-123mm. The 360 ° inner wall lens is an excellent solution for detecting the interior of objects such as cylinders, holes, bottles, threaded objects, and mechanical parts.