Below is some zebra scan engine part number with their meaning. Different scan engine come with it own specific purpose. For distant scanner, In order to have maximum reading range, the sample barcode use must be follow the specification.
SE965 Standard Range 1D Scan Engine Scanning range - from near contact to as far as 15 ft./4.5 m.
SE1524 Lorax 1D Long Range Scan Engine Scanning range - from near contact to as far as 45 ft./13.71 m away
SE4500SR Blockbuster 2D Imager Come with patent-pending fast pulse illumination and a fast sensor shutter speed that can capture 60 frames per minute,
SE4500HD Blockbuster 2D Imager Come with DPM Ideal for DPM application with low colour contrast.
SE4600 Long Range 2D Imager (CE and WM OS only) Scanning range - from 8 in./20.32 cm to as far as 30 ft./9.14 m
away
SE4750SR Imager Standard Range - Best for fast performance standard barcode reading
SE4750MR Imager Medium Range - Better for fast performance bigger barcode reading compare SE4750SR
SE4850 Extended Range 2D Imager Scanning range - from 3 in./7.62 cm to as far as 70 ft./21.4 m away