An angle type optical connector enables a splicing operation of an optical fiber cable accurately and stably without requiring skilled labor and having a superior on-site installation property. In an inflated state, said covering forms at least the following elements: a central holding element, at least three umbrella strut elements extending away from the central holding element, and at least one umbrella surface element stretched out by the umbrella strut elements. The 2-dimensional transfer function representing the motion is derived using blind estimation techniques or by using information from sensors that detect the motion. The perforations are varied over the length of the tampon so that a differentiated expansion of the tampon while absorbing fluid is achievable.