Abstract: The present invention is a method of folding a cardboard along a fold-line. The cardboard consists of an outside layer, a middle layer and an inside layer. The method includes the step of using a laser system to cut a first slot and a second slot in the inside layer. The first and second slots are disposed parallel to the fold-line which is disposed between the first and second slots. The method also includes the step of folding the cardboard along the fold-line. When the outside layer is pulled tight the inside layer and the middle layer are pushed inward. The first and second slots must be wide enough to allow the inside layer to easily deform when the cardboard is folded.

Abstract: A method and apparatus for calibrating the scan of a laser over a planar surface that includes defining an error table having x-dimension and y-dimension correction factors, and also a scale factor, for each of a plurality of regions of the planar target surface. The scale factor is initially set to a value to account for differences in the size of the image field to be scanned and the overall scan field in the CAD data base. Adjustment is performed to each scale factor to account for theoretical differences due to the use of a perpendicular galvanometer-driven mirror scanning system. A sheet with a large number of square cells is then placed over the target surface, after rotational alignment, and the laser marks each cell. The sheet is then converted into digital form by scanning, and the location of the laser mark relative to the centroid of the cell is used to update the correction factors for that cell.

Abstract: A transversely RF excited gas laser with an internally folded resonator includes an elongated chamber of cross-sectional dimensions suitable for confining a laser gas discharge, a plurality of reflectors and a laser gas. The reflectors form a stable folded laser resonator cavity of a compact geometry in order to efficiently extract laser power from the laser resonator cavity. There are at least two of the reflectors and at least one of the plurality of reflectors is concave. The laser gas is disposed in the folded resonator cavity which reflect and guide light energy from the laser gas discharge within the elongated chamber. The transversely RF excited gas laser with an internally folded resonator also includes a pair of electrodes and a pair of cooling electrodes. The electrodes are transversely disposed on the elongated chamber and excite the laser gas. The cooling electrodes are transversely disposed on the elongated chamber and electrically coupled to ground.