Back frame of flat panel display device, method for manufacturing back frame, and backlight system

A method for making a back frame of a flat panel display device, comprising:

• manufacturing at least two primary assembling pieces of the back frame;
• and
• joining the at least two primary assembling pieces to each other, the joining of the at least two primary assembling pieces being realized by using multiple spaced joining spots;
• wherein the step of manufacturing at least two primary assembling pieces comprises:
• manufacturing at least first and second primary assembling pieces, in which the first primary assembling piece has an end forming at least two joint sections, each of the joint sections having a structure that mates a corresponding end of the second primary assembling piece;
• wherein the step of joining the at least two primary assembling pieces comprises:
• selecting one joint section of the at least two joint sections according to a size of the back frame to join the corresponding end of the second primary assembling piece;
• and
• wherein when an additional joint section is present between joining location of the second primary assembling piece and the end of the first primary assembling piece, before or after the step of selecting one joint section of the at least two joint sections according to a size of the back frame to join the corresponding end of the second primary assembling piece, the additional joint section of the first primary assembling piece that is located outward of the joining position of the second primary assembling piece is trimmed off.