The present invention provides an apparatus and method for sensing subsurface data. In the methods, the hollow cathode plasma is generated by a gas introduced between a hollow cathode in which a plurality of lower grooves where plasma is generated is defined in a bottom surface thereof and a baffle in which a plurality of injection holes is defined. The data samples stored in the de-interleaving memory array are de-interleaved sub-array by sub-array. To accomplish this, the laser printer of a paper ejecting type and the other laser printer of a non-paper ejecting type will execute interrupt print processing when the received job is a secured print job and there is any other job being processed if there are a plurality of paper discharging ports or execute promote print processing if there is only one paper discharging port. A backbone mask layout is then generated based on one of the sets of nodes.