A head-mounted display device comprising: a visor assembly containing a plurality of electronic components (103, 172) that generate heat when in operation, the visor assembly including a display component to display an image directly in front of an eye of a user; a head fitting assembly, coupled to the visor assembly, by which the head-mounted display device can be worn on a head of the user, the head fitting assembly including a plurality of curved, elongate side arms (24A, 24B), each flexibly coupled to a different end of the visor assembly, each of said side arms including a heat dissipation structure; and a plurality of multi-layer flexible thermal conduits (82A, 82B), a first multi-layer flexible thermal conduit which is coupled to the visor assembly and to a first side arm and a second multi-layer flexible thermal conduit which is coupled to the visor assembly and to a second side arm, each of said multi-layer flexible thermal conduits configured to convey heat generated by at least one of the plurality of electronic components to the heat dissipation structure in a corresponding side arm, each of said multi-layer flexible thermal conduits including a plurality of flat, elongate, flexible thermal conduit strips, wherein each of said multi-layer flexible thermal conduits includes a plurality of stacked, flexible, thermal conductive strips, a surface of each strip of the plurality of stacked, flexible, thermally conductive strips being adjacent to a surface of another strip of the plurality of stacked, flexible, thermally conductive strips; wherein the plurality of layers of the multi-layer flexible thermal conduits are not affixed to each other in a region where the head fitting assembly is flexibly coupled to the visor assembly. a visor assembly containing a plurality of electronic components (103, 172) that generate heat when in operation, the visor assembly including a display component to display an image directly in front of an eye of a user; a head fitting assembly, coupled to the visor assembly, by which the head-mounted display device can be worn on a head of the user, the head fitting assembly including a plurality of curved, elongate side arms (24A, 24B), each flexibly coupled to a different end of the visor assembly, each of said side arms including a heat dissipation structure; and a plurality of multi-layer flexible thermal conduits (82A, 82B), a first multi-layer flexible thermal conduit which is coupled to the visor assembly and to a first side arm and a second multi-layer flexible thermal conduit which is coupled to the visor assembly and to a second side arm, each of said multi-layer flexible thermal conduits configured to convey heat generated by at least one of the plurality of electronic components to the heat dissipation structure in a corresponding side arm, each of said multi-layer flexible thermal conduits including a plurality of flat, elongate, flexible thermal conduit strips, wherein each of said multi-layer flexible thermal conduits includes a plurality of stacked, flexible, thermal conductive strips, a surface of each strip of the plurality of stacked, flexible, thermally conductive strips being adjacent to a surface of another strip of the plurality of stacked, flexible, thermally conductive strips; wherein the plurality of layers of the multi-layer flexible thermal conduits are not affixed to each other in a region where the head fitting assembly is flexibly coupled to the visor assembly.