Cognex has announced the addition of liquid lens optics for the DataMan 300 series of fi xed-mount barcode readers. The company says this new accessory allows any DataMan 300 reader to be upgraded from fi xed focus to autofocus. Liquid lens variable autofocus technology is suitable for applications that require a large depth of fi eld or when refocusing is needed after a product changeover. An intelligent tuning feature automatically selects the optimum settings for the integrated lighting and for the autofocus optics for each application, says Cognex. The liquid lens can also be adjusted with software or serial commands without having to touch the reader. DataMan 300 is available in two models. The DataMan 300 has a resolution of 800x600 pixels and the DataMan 302 has a higher resolution of 1280x1024 pixels.