DIMMING MECHANISM, VEHICLE LAMP MODULE, VEHICLE LAMP, AND VEHICLE

A dimming mechanism, which is used for dimming a lighting unit (2) and comprises a fixed ball head connecting piece (1a), a first adjustable ball head connecting piece (1b), and a second adjustable ball head connecting piece (1c); one end of the fixed ball head connecting piece (1a) is connected to the lighting unit (2), and the other end is connected to a support frame or lamp body (3); one end of the first adjustable ball head connecting piece (1b) is connected to the lighting unit (2), and the other end is supported on the support frame or lamp body (3); and a sliding slot (4) is provided on the lighting unit (2), and one end of the second adjustable ball head connecting piece (1c) is slidingly connected to the sliding slot (4) so that the sliding slot (4) is, by means of the back and forth motion of the second adjustable ball head connecting piece (1c), driven to rotate, and the lighting unit (2) is, by means of the rotation of the sliding slot (4), driven to rotate so as to achieve dimming in a second direction. Further disclosed are a vehicle lamp module comprising a dimming mechanism, a vehicle lamp, and a vehicle. The dimming mechanism can achieve the miniaturization of the dimensions of the vehicle lamp module in the second direction, and can improve the precision of dimming in the second direction.