Optical Mark Recognition (OMR) is a method of data input from paper forms to computers. The paper forms used for such purpose are called “optical forms”. With OMR, data can be collected from people without being directly connected to the system. The method is named as “optical”, because light generating and detecting devices are used to sense existence of marks on a form.

OMR technology is similar to punched cards and paper tapes which are earlier methods of data entry into electronic (and even mechanical) systems. The basic difference between the two technologies is punch cards are marked using physical holes whereas optical forms are marked by filling mark areas using a pencil. Puched cards have been used to store and load program and data in older computer systems. OMR, on the other hand, is used to enter human produced data.

Optical forms have markable areas (called bubbles) which represent the information on the form. A filled bubble may correspond to a letter in a textual field, a digit in a numeric value or a binary value (1/0) as defined by the design of the form. Bubble shapes and accepted marks may vary depending on the OMR technology used. Some systems accept crosses and checks as marks, others may require completely filling.

Once the raw data is collected, it can be utilized by application software to store, analyse and score. As an example, the reponses of students on an answer sheet (which is an example of optical forms) can be processed by a scorer (such as Pilot Assessment) to score individual forms, generate exam and question statistics, combine OMR data with other data (such as question-outcome mapping, student details, student-class mapping) to produce more detailed statistical analysis.

Optical Mark Recognition (OMR) is used to collect information, there are many applications of this technology. Some applications of OMR are:

• Surveys, questionnaires
• Elections and ballots
• Time sheets
• Psychometrics tests
• School examinations
• Lotteries and other games
• Application and registry forms
   

The primary benfit of OMR is saving time and reducing errors. Computerized counting of ballot votes reduce the time to get the results drastically. Examinations over thousands of students can be scored and analyzed in minutes, with much less errors compared to manual methods.

Today Optical Mark Recognition is achieved using two types of devices:

Dedicated OMR scanners:

• These are specially designed hardware for scanning OMR forms. These devices cannot be used for other purposes.
• The output of scanning is the actual data.
• Scanning speed ranges from 1.000 forms/hour to 8.000 forms/hour (with single read-head).
• Depending on the read-head techonology, special type of markers (pencils) may be required.
• Forms have strict specifications (color, size, weight, timing marks).
• Scanners might present other features: barcode reading, form image scanning, output tray for forms with error.

Image Scanners:

• These scanners are multi-purpose document scanners that has an ADF (automatic document feeder) and an input tray.
• The output of scanning is a digital image. Image format, resolution and color dept may vary from device to device, and can be configured at each scan session.
• Mark sensing is achieved using an OMR software (such as MarkReader), which is basically an image processing application. The software converts scanned images to tabular data by first sensing marks, and then processing mark states using form configuration.
• OMR software may offer features other than mark sensing: barcode reading, image clips, OCR and ICR.
• Scanning speed ranges from 100 forms/hour to 18.000 forms/hour.
• Forms can be printed using office printers and form design can be changed easily.