Linear light-emitting device, lamp assembly, and vehicle

A lamp assembly, comprising:

• a linear light-emitting device, with the linear light-emitting device includes a plurality of linear light-emitting elements, each of the plurality of linear light-emitting elements being a laterally light-emitting element for jointly forming a lateral light exit region of the linear light-emitting device, wherein for at least a portion of the linear light-emitting device, each linear light-emitting element includes a core layer, which is rod-shaped, wherein at least one end side of the core layer is configured to receive and input light from a light source, a cladding layer covering the outer side of the core layer, wherein the refractive index of the cladding layer is lower than that of the core layer, and light from the core layer enters the cladding layer through refraction, and a reflective layer formed on the outer side of the cladding layer, the reflective layer being configured to reflect light from the cladding layer towards the lateral light exit region;
• a light source module, the light source module being configured to emit light towards at least one end of the linear light-emitting device;
• and
• a coupler, the coupler being configured to fix a relative position between the linear light-emitting device and the light source module.