Collimator device, a lighting device, a lamp and a luminaire

A lighting device comprising a light source for providing light source light and a collimator device, and being arranged in the optical path of the light source light;

• the collimator device comprising:
• a collimator panel having a first end face for receiving input light and a second end face for providing collimated light, wherein the second end face is opposite to the first end face,
• the collimator panel comprising a plurality of walls extending between the first end face and the second end face for obtaining a grid of cells, the cells extending between the first end face and the second end face for obtaining the collimated light, at least the plurality of the walls being arranged for obtaining cross-sections of the associated cells forming an auxetic structure, and
• wherein the collimator panel is deformable from a first structure into a second structure and back by changing the cross-sections of the associated cells to change the collimated light having a first spatial distribution into collimated light having a second spatial distribution, wherein the first spatial distribution is different from the second spatial distribution.