Recording medium cartridge and method of welding upper and lower halves of recording medium cartridge

Abstract

When a recording medium cartridge having a flat housing which holds therein a recording medium is produced by butt-splicing peripheral walls of upper and lower shell halves by welding the upper and lower shell halves together at a plurality of points at the peripheral walls, the welding is performed with a center of a laser spot for welding being offset upward or downward from a joint between the opposed abutment portions of the peripheral walls of the upper and lower shell halves, whereby the laser beam can be efficiently prevented from entering the housing through clearance between the opposed abutment portions of the peripheral walls of the upper and lower shell halves during welding.

Dependencies are inferred from the claim text.