Input Devices : OMR

An optical mark recognition (also known as OMR or mark sense) system reads marks made by pencil on a printed form into the computer. OMR systems are used by examination boards to collect the answers to multiple choice examinations and to purchase lottery tickets. Here is an example answer grid for an examination :

The student answers each question by drawing a line in pencil in the box that he/she thinks is the correct one. The answer grid is printed in a special coloured ink called that the OMR system will ignore. Marks down the side of the form are used to automatically line the form up in the reader so that it can be read. The reader detects where the marks are placed by shining a light at the page and measuring the amount of light reflected. Less light is reflected where the marks have been made. A pile of forms collected at the end of an examination can be put into a tray (called a bin). The reader will go through each form in turn and record the candidates marks.

Input using OMR is accurate and very fast. Problems can occur if the OMR forms get creased as the reader may jam.

GCSE ICT Companion 04 - (C) P Meakin 2004