Method of analyzing a light distribution of a vehicle headlight

A vehicle headlight analyzer comprising:

• an image sensor being arranged to detect an image of a light distribution of a vehicle headlight, the vehicle headlight comprising an optical imaging device, and
• an evaluation device,
• the evaluation device being adapted for
• determining a brightness of at least a part of pixels of the image within a multitude of columns of the image, the columns being perpendicular to a horizon in the image,
• determining a probability of a cutoff within each of the multitude of columns based on a relative change of brightness between neighboring pixels of the image within the columns, wherein the probability is the higher the higher the relative change of brightness is,
• determining a cutoff line based on the probability of the cutoff within the multitude of columns of the image,
• comparing the cutoff line with a reference cutoff line,
• determining a quality of the light distribution characterized by the cutoff line by means of the comparison, and
• determining by global or local deviations of the cutoff line from the reference cutoff line whether a reduction in quality of the light distribution is caused by a light source of the vehicle headlight, or the optical imaging device of the vehicle headlight, or a relative position of the light source with respect to the optical imaging device.