Test protocol for comparing two-dimensional bar code hand-held reader technologies

Current advances in reader technology offer users of two-dimensional bar codes many choices in selecting a hand-held reader for their particular application. Specifications exist that describe required functionality for various scanning technologies, but little work has been done in the published literature with respect to assessing the relative performances of these technologies when actually incorporated into a hand-held unit. In this paper, a suite of standard tests is presented to measure the decode time of hand-held readers. These tests were applied to a PDF417 two-dimensional bar code symbol and used to compare the performance of five newly developed hand-held readers over four different reader technologies. The technologies included laser scanning, linear CCD, area CCD, and CMOS technology. The tests focused on the following factors that typically affect decode time: lighting conditions, reading distance, orientation angles of the reader, and use of the readers in a typical freehand application. Results show the tests to be a valid means for comparing performance of differing hand-held reader technologies typically used for two-dimensional dimbologies.