A hair removing device with a lotion applicator includes a housing, a hair removing head mounted to the housing and adapted to be held against a user’s skin for hair depilation or hair epilation, an applicator which dispenses a lotion on the user’s skin, a tank holding the lotion and a lotion supply mechanism for supplying the lotion from the tank to the applicator. The rupture detector includes a conductive member attached to a portion of the transparent member. A capturing unit having a detection range lying between the detection ranges of the tracking unit and of the surveying device is also present. The apparatus enlarges the difference in the direction of the particular axis, and calculates a position of the apex of the second three-dimensional model after the enlargement. Corresponding methods are also disclosed. The device comprises a video camera which is directable towards the welding zone for recording the welding process in the form of video signals transmitted, via an image processing unit, to a video display unit, which the user is able to view and which is placed in or on the inside of the shielding element.