Brief History of the Gerber File Format
The world over, a majority of designers and fabricators follow the Gerber RS-274X as the de facto standard when designing and fabricating their PCBs. The evidence of its popularity notwithstanding, Gerber has a number of practical limitations. Often, these limitations lead to a variety of problems when fabricating PCBs.
Ucamco developed the Gerber file format in the 1960s, when it was the Gerber Systems Corporation, and a leading provider of early photo-plotter systems using numerical controls. Their first format, RS-274D, was a subset of EIA RS-274-D, supporting their vector-based photo-plotters. Widely adopted, RS-247D remained the standard format for vector-based photo-plotters until the 1980s.
Raster scan plotters began replacing vector-based photo-plotters in the 1980s. These newer plotters were bitmap-based, requiring a completely different data format. Consequently, in 1998, Barco ETS, who had acquired Gerber Systems, released a single standard image format, and named it the Extended Gerber or GerberX. This was later renamed as the RS-274X format and is still in use today.
The latest Gerber RS-274X presents a complete image description format. Therefore, the Extended Gerber file holds the complete description of a layer of the PCB, and provides the operator with everything necessary to generate a PCB image, including the definition of any aperture shape. Requiring no external aperture files, painting, or vector-fill, the RS-274X standard specifies all pads and planes clearly and simply. Its simplicity has made it the de facto standard followed by nearly 90% of the world’s PCB designers and fabricators.