What is an optical answer sheet? Explained in Details

What is an optical answer sheet? Explained in Details

An optical answer sheet, also known as a bubble sheet, is a special type of form used in multiple choice question examinations. Optical mark recognition (OMR) is used to detect these answers. The Scantron Corporation creates many optical answer sheets, although certain uses require their own customised system. 

What is Optical Answer Sheet

Optical answer sheets usually have a set of blank  spaces or boxes that correspond to each question, often on separate sheets of paper. Bar codes may mark the sheet for automatic processing, and each series of ovals filled will return a certain value when read. In this way students' answers can be digitally recorded, or identity given.

 How do optical answer sheets work?

Optical answer sheets are read by an optical mark reader (OMR). The OMR scans the sheet for marks in the ovals and converts them into a digital format. The digital format is then processed by a computer to grade the exam.

Advantages of optical answer sheets

There are many advantages to using optical answer sheets. They are:

  1. OMR can grade exams much faster than manual grading. This can save time and money, especially for large-scale exams.
  2. OMR is very accurate. Human grading can be subjective and prone to errors, but OMR is not.
  3. OMR is a very efficient way to grade exams. It can handle large numbers of exams quickly and accurately.

Disadvantages of optical answer sheets

There are a few disadvantages to using optical answer sheets. They are:

  1. Cost: OMR machines can be expensive. However, the cost of OMR machines is often offset by the savings in time and money that they can provide.
  2. Training: OMR machines require training to operate. However, the training is usually not very difficult.
  3. Maintenance: OMR machines require regular maintenance. However, the maintenance is usually not very difficult.

Tips to use optical answer sheets:

  1. Make sure you fill in the ovals completely and neatly.
  2. Always use pen or pencil provided by exam centre.
  3. Do not erase any marks you have made.
  4. If you make a mistake, cross out the old mark and make a new one.
  5. Do not fold or crease the answer sheet.
  6. Handle the answer sheet carefully to avoid damaging it.


Optical answer sheets are a valuable tool for grading exams. They are fast, accurate, and efficient. If you are looking for a way to grade exams quickly and accurately, then optical answer sheets are a good option.