Apparatus for reducing weight and thickness of a portable computer

1. A portable computer, comprising:

a lower housing for accommodating electronic elements therein;

an upper housing having an opening inside, wherein said upper housing further includes a periphery connected to said lower housing and a main bridge structure connected to said periphery for providing structural support to said upper housing in said opening and for accommodating a display module therein, wherein said periphery is in a rectangular shape made up of a first and second long edges along with a first and second short edges, wherein said main bridge structure consists of a first bridge structure connecting a midpoint of said first long edge to a midpoint of said first short edge, a second bridge structure connecting said midpoint of said first long edge to a midpoint of said second short edge, a third bridge structure connecting said midpoint of said first short edge to a midpoint of said second long edge, and a fourth bridge structure connecting said midpoint of said second short edge to said midpoint of said second long edge; and

a cosmetic cover for covering said upper housing.

2. The portable computer of claim 1 , wherein said cosmetic cover is made of synthetic resin, and said upper housing is made of metal.

3. The portable computer of claim 1 , wherein said portable computer includes an antenna located outside said upper housing covered by said cosmetic cover.

4. The portable computer of claim 1 , wherein said main bridge structure includes a rib formed in a longitudinal direction thereof, wherein said rib is formed in an arch shape such that a thickness of said rib increases from said periphery towards a middle of said rib.

5. The portable computer of claim 1 , wherein said upper housing further includes a sub-bridge structure having a rib, wherein said sub-bridge structure is arranged in each opening divided by said main bridge structure.

6. The portable computer of claim 5 , wherein said rib of said sub-bridge structure is connected to said main bridge structure and said periphery to form a plurality of opening cells.

7. The portable computer of claim 6 , wherein a surface obtained by connecting a top of said main bridge structure to a top of said sub-bridge structure is configured to match an inner surface of said cosmetic cover.

8. The portable computer of claim 7 , wherein an inner surface of said cosmetic cover is formed in a dome shape, and a top of said main bridge structure and a top of said sub-bridge structure are formed in a dome shape so as to be attached to said inner surface of said cosmetic cover.

9. The portable computer of claim 6 , wherein said sub-bridge structure is configured to include a plurality of hexagon cell structures.

10. A portable computer, comprising:

a lower housing for accommodating electronic elements therein;

a display module connected to said electronic elements;

an upper housing, connected to said lower housing, for accommodating said display module therein, wherein said upper housing includes:

a rectangular shape periphery made up of a first and second long edges along with a first and second short edges to form an opening;

a main bridge structure having a bottom for connecting edges of said periphery so as to cross said opening and a plurality of ribs reinforcing said bottom, wherein said main bridge structure consists of a first bridge structure connecting a midpoint of said first long edge to a midpoint of said first short edge, a second bridge structure connecting said midpoint of said first long edge to a midpoint of said second short edge, a third bridge structure connecting said midpoint of said first short edge to a midpoint of said second long edge, and a fourth bridge structure connecting said midpoint of said second short edge to said midpoint of said second long edge;

an antenna, located outside said upper housing, for connecting to said electronic elements; and

a cosmetic cover for covering said upper housing and said antenna.

11. The portable computer of claim 10 , wherein said upper housing further includes a sub-bridge structure having a rib, wherein said sub-bridge structure is arranged in each opening divided by said main bridge structure.

12. The portable computer of claim 11 , wherein a surface obtained by connecting a top of each rib of said main bridge structure and a top of a rib of said sub-bridge structure.

13. The portable computer of claim 11 , wherein said upper housing includes a cable duct having a cable connected to said antenna, wherein a side wall of said cable duct forms a part of said rib of said sub-bridge structure.

14. The portable computer of claim 13 , wherein said cable duct obliquely crosses said main bridge structure so as to cut out each of said plurality of ribs, and a crossing angle between said main bridge structure and said cable duct and said width of said cable duct are determined such that a distance in which two ribs located at outermost sides in one main bridge structure overlap each other without being cut out together between cut parts in a direction perpendicular to said ribs, is included.