Method and device for determining a mass proportion of a wall section of a plastic bottle

摘要

The method involves irradiating an irradiation region (13) of a bottle side wall with a light (15) i.e. infrared or UV light. Light diffusion of a light along a detection region (17) of the side wall on a side of a bottle (2) is detected, where the side is turned towards the irradiation region. Mass distribution of the bottle side wall is calculated from the light diffusion. Mass-fraction of a mass of the side wall is determined based on the mass distribution. The light diffusion in a camera image is detected, where the detection region is formed in the camera image. An independent claim is also included for a device for determining mass and/or mass proportion of a wall section of a plastic surface, such as a section at a region of a bottle shoulder and/or a bottle neck.