Duplex Digital Document Scanner (ERDH)

A duplex digital document scanner, sometimes abbreviated as ERDH, refers to any copier or MFP that can take a two-sided multi-page original document, scan it in once, and generate multiple collated copies. This represents the convergence of several technologies: duplex scanning (both sides), digital memory (storing the scanned document), and electronic collation (producing ordered sets). This capability is standard in modern digital copiers but represents a significant productivity advance over analog copiers that required separate scans for each copy.