Which input device is used for reading answers to questions in a test or survey?

Concept

Optical Mark Recognition (OMR) is an input technique in which a scanner detects the presence or absence of marks (filled bubbles, ticks or shaded boxes) placed at predetermined positions on a printed sheet. Because it senses the position of a mark rather than interpreting characters, it is the standard method for capturing responses on answer sheets, ballots and survey forms.

Application

In a test or survey, the candidate shades pre-printed bubbles for each chosen response. The OMR device shines light across the sheet and measures reflected intensity at each bubble location: a darkened bubble reflects less light and is registered as a selected answer. This lets thousands of sheets be read and scored automatically, which is exactly the task described in the question — reading the answers marked on a response sheet.

Contrast

The other input devices operate on different kinds of data, so none of them reads positional marks on an answer sheet:

• OCR converts images of typed or handwritten characters into machine-encoded text — it interprets character shapes, not mark positions.

• A barcode reader decodes the pattern of parallel bars and spaces in a barcode to look up a stored code or identifier.

• MICR reads characters printed in magnetic ink, used chiefly to process the account and cheque numbers along the bottom of bank cheques.

Hence the device that reads marked answers on test or survey sheets is OMR.