Basic Information About QR Code

08/05/2024

Basic information about QR code®

Currently, QR code is widely used in digital marketing and advertising, as it allows for quick communication with customers and provides content to end users. This can be links to websites, digital discount coupons, tickets for various transport services, etc.

To effectively use QR code in any of these areas, it is necessary to understand its concept and development technology well.

What is QR code?

QR code

QR code stands for Quick Response code. It is a two-dimensional (2-D) matrix code that belongs to a large set of machine-readable codes. All these codes are called barcodes, regardless of whether they include stripes, squares, or elements of another shape.

Let's look at 1-D and 2-D codes. Compared to the first type, 2-D codes can contain a larger amount of data while taking up less space. However, QR code contains much more data compared to the aforementioned types of codes. In addition, QR code also has a more advanced error correction method and higher reading speed.

Barcodes visually represent information, like any writing, but not for people - for machines. A scanner reads the code using special optical systems and software for reading barcodes. The rules for creating barcode (like grammar) and the set of symbols it uses (its alphabet) are its symbolism.

The main idea of 1-D barcodes

Basic barcode symbols can be divided into two types: one-dimensional, or linear, and two-dimensional.

One-dimensional (1-D) barcodes, such as Universal Product Code (UPC), are widely used in trade, on price tags, and packaging of goods. They consist of vertical bars and spaces. These codes are classified as one-dimensional, because the information encrypted in them is transmitted only by the difference in their horizontal size - the width of the bars and spaces - and their left-to-right position.

The height of the barcode columns does not affect the encrypted information. Therefore, the software reads both options without any difference.

The only thing that matters is the width and order of the bars, not their height.

2-D codes - the next level

1-D barcodes appeared in 1966 and quickly became popular. However, time does not stand still, and soon there was a need for new types of codes, smaller in size but more informative at the same time.

Later attempts were made to increase the informativeness of the barcode. This involved either increasing the number of bars or creating a layout with multiple codes. All this led to an increase in the size of the barcode and, consequently, to the complicating of reading and printing costs.

That is why 2-D codes were created. Initially, they repeated the same linear symbols vertically, and later they began to make them in the form of matrix codes. The code was formed from small symmetrical elements, square or rectangular in shape.


Multiple-barcode Layout	2-D stacked barcode	2-D matrix code

Barcodes

2-D matrix codes contain information in both vertical and horizontal directions, therefore they have a fairly high data density in a small size. However, further improvements with QR code were still ahead.

In the following table are characteristics and features of some typical 2-D codes.

	QR code	PDF417	DataMatrix	MaxiCode

Developer	DENSO Wave	Symbol Technologies	RVSI Acuity CiMatrix	UPS
Type	Matrix	Stacked barcode	Matrix	Matrix
Numeric	7,089	2,710	3,116	138
Alphanumeric	4,296	1,850	2,355	93
Binary	2,953	1,018	1,556	-
Japanese, Chinese or Korean characters	1,817	554	778	-
Main features	Large capacity, small size, highspeed scanning	Large capacity	Small size	High-speed scanning
Main applications	All categories	Office automation	Factory automation	Logistics
Standards	AIM, JIS, ISO	AIM, ISO	AIM, ISO	AIM, ISO

How QR code works

<-Contains NO data->

<-Contains data->

QR code belongs to the type of 2-D matrix codes. In this type of code, information is encrypted not by the position and width of bars and spaces in the horizontal dimension, but by the arrangement of dark and light modules in columns and rows, both horizontally and vertically.

Under each dark or light module of the QR code, a 0 or 1 is encrypted so the computer can read it.

The modules of the QR code perform different functions. Some contain actual data, while others are collected in functional templates that improve readability and provide character alignment, error correction, and distortion compensation. There is also a synchronization template - it allows the reader to determine the size of the symbol. Additionally, there is a mandatory "quiet zone." It is a buffer area four modules wide that is needed to ensure that text or markup around it is not mistaken for data in the QR code.

Reading ordinary two-dimensional matrix codes took a long time because the reader needed to find the symbol code, determine its orientation angle, position (x and y coordinates), and size.

Therefore, the QR code was developed using special position determination templates. They were located in three corners of each symbol. The templates have a symmetric scanning line relationship of 1:1:3:1:1, which allows them to be scanned from any direction within a complete 360-degree range. In addition, the templates are interconnected, providing quick access to relevant information about the angle, position, and size contained on the code's periphery.

As a result, the QR code is read 20 times faster than a normal matrix code. Additionally, scanning equipment can search for templates, increasing overall speed through simultaneous image capture and data processing.

QR code symbol versions

QR codes can be generated in 40 different symbol versions, from 21 x 21 modules (version 1) to 177 x 177 modules (version 40).

Each higher symbol version has 4 additional modules on each side (16 additional modules per symbol) and can have proportionally more data. The maximum data capacity for a given symbol is determined by its version, symbol type, and error correction level.

Error correction in QR code

The QR code has powerful error correction capabilities by adding Reed-Solomon codes to the original data. This mathematical error correction method allows the scanning machine to read QR code symbols even in cases of contamination or damage.

There are four levels of error correction available. The higher the level, the better the error correction, but also the higher the QR code version.

Level of error correction	Approximate correction volume	Comments
L	7%	Recommended for qr codes that will not be printed. Those that will be displayed on screens.
M	15%	Recommended for wear resistant printing. For moving objects such as transportation.
Q	25%	Recommended for QR codes that will be actively worn or contaminated.
H	30%	Recommended for those that contain a logo and will be actively worn out.

When choosing the error correction level, factors of the surrounding environment and the desired size of the QR code symbol should be taken into account.

For example, for plants, factories and other places where the QR code may get dirty or damaged, it is better to choose level Q (error correction 25%) or H (30%). In clean places and codes with a large amount of data, level L (7%) can be chosen. Overall, the most popular level is M (15%).

Benefits of QR Code

The unique design of the QR code provides it with a huge number of advantages, including:

Fast scanning in all directions: The QR code can be read at any angle within 360 degrees thanks to the pattern of position determination at three corners of each symbol. Therefore, there is no need to keep the scanner at the same level as the code. In addition, the position determination pattern eliminates any background obstacles, so the QR code is read steadily and quickly.

Large memory capacity for storing data: One QR code symbol can contain up to 7089 digits. This is 200 times more than can be contained in a standard 1-D barcode.

300 alphanumeric characters can be contained in such a QR code symbol.

Compactness: Data contained in a 1-D barcode will only occupy 1/10 of the data volume of a QR code.

Error correction: A QR code symbol can be read and decoded, even if about 30% of the data is dirty or damaged. Of course, this also depends on the chosen error correction level.

Diversity of data types: QR code can handle numbers, alphabet characters, symbols, Japanese, Chinese or Korean characters, and binary data.

Distortion compensation: The QR code symbol can be read even if it is on a curved or distorted surface.

Connectivity (Structured application): The QR code symbol can be divided into 16 smaller symbols to fit in long and narrow spaces. Smaller symbols are read as a single code, and the scanning order does not matter in this case.

Direct marking: If conditions of low contrast do not allow to read the QR code, it can be printed, laser engraved, or applied by the DPM method directly on the product.

Use of QR code

It is noteworthy that initially the QR code was developed for tracking automotive components and systems in the manufacturing and delivery processes. However, it quickly gained wide popularity in virtually all areas of application of standard barcodes, as well as in some new areas.

Traditional areas of application include:

• Manufacturing

Product tracking

Process management

Order and time tracking

Inventory and equipment management

• Warehousing and logistics

Goods tracking

• Retail

Product identification at the point of purchase

Sales management

Inventory control

• Healthcare

Medical documentation management

Patient identification

Medication tracking

Equipment and device tracking

• Life sciences

Sample tracking

• Transportation

Fleet management

Ticket and boarding pass sale

• Office automation

Document Management

• Marketing and Advertising

Mobile marketing

Electronic tickets, payments, coupons, and loyalty programs

Using QR codes in marketing and advertising.

Initially, mobile marketing was popular in the Netherlands, Korea, and Japan. However, recently its popularity has been growing in North America. Here, QR codes are used in advertising and printing, as well as on billboards, posters, clothing, dishes, and other items. By scanning a QR code with a smartphone, the user can go to a website or get a discount coupon, special offer, product information, or store information.

QR codes can now be read even from the display of a smartphone using special scanners. Such a code can contain a ticket to an event or a coupon for a purchase, a payment receipt, a loyalty card, etc.

Generating QR Codes

DENSO Wave Incorporated, the inventor of the QR code and owner of the QR code trademark, made this type of code freely available to the public. Therefore, a large number of websites now contain online QR code generators or downloadable software for generating codes.

However, such code generators and software do not have an International Organization for Standardization (ISO) certificate, so it is impossible to determine if they comply with the ISO 18004 standard based on the DENSO Wave patent. As a result, such code symbols may not be readable by some devices, or the reading quality may be reduced.

(Simple test: generate the same code symbol using several different online generators. Differences in module placement will be immediately obvious).

The most inconvenient thing is that non-standardized ISO generators cannot determine the minimum print size of a QR code symbol. And if the symbol is printed smaller than the minimum size, considering the data volume, symbol version, and resolution according to ISO, its readability will be significantly reduced.

If a QR code is generated using software that does not comply with ISO, it will be difficult to use, especially if it is intended for smartphone reading. It is also worth noting that QR code reading software, like QR code generation software, does not always rely on the ISO standard.

In order to guarantee that a QR code will be successfully read by the largest percentage of devices, it is important to use code generation software offered only by a reputable manufacturer that can be trusted to comply with ISO specifications.

Reading QR Codes: 5 Necessary Things for a 2D Scanner or Terminal

1. High Reading Speed: Operator efficiency depends on scanning speed and the ability to do it remotely. Therefore, it is best to look for devices with advanced CCD scanning technology. With it, high-density codes or difficult-to-read codes can be scanned.

2. Ease of Use: To reduce operator fatigue and, as a result, increase work speed, it is better to choose convenient models—lightweight, ergonomic, with a large screen.

3. Structural Integrity: In harsh operating conditions, manual scanners and terminals are sometimes subjected to rough handling, impacts, and falls. Moisture-resistant, dust-proof, and shock-resistant devices will be a good investment in technical equipment.

4. Battery life: It is worth paying attention to scanner models with energy-saving functions - this way the battery will last longer, preserving its service life.

5. Reputation and experience of the manufacturer: Look for popular manufacturers with good reviews, recommendations, and a long service life.

About DENSO ADC Company

DENSO Wave - one of the world's largest manufacturers of mobile data collection systems. It includes DENSO ADC, the American division of DENSO Wave Incorporated, a pioneer in CCD technologies and the inventor of the revolutionary QR code.

The company has a wide range of advanced technologies and produces portable 1D and 2D terminals and scanners. These devices are characterized by a light and ergonomic design; a robust construction that withstands the most challenging operating conditions; good water and dust resistance; energy-saving features that extend the device's service life; connectivity via Bluetooth, USB, serial or keyboard interfaces or connectivity via 802.11b, Bluetooth or GPRS; as well as cost-effectiveness.

For more detailed information, visit the DENSO ADC website at www.denso-adc.com.

DENSO ADC is a trademark of DENSO Corporation based in Kariya, Japan. DENSO is a leading global supplier of advanced technologies, systems, and components for electronics, information security, thermal and energy industries. The company's clients include all major global automakers. DENSO has over 200 subsidiaries and affiliated companies in 35 countries and regions (including Japan) worldwide. It also employs approximately 120,000 people. Consolidated global sales for the fiscal year ended March 31, 2011, totaled $37.7 billion USD. In the previous fiscal year, DENSO spent 9.3% of its global sales on research and development. DENSO shares are listed on the Tokyo and Nagoya stock exchanges. In North America, DENSO has 13,000 employees, and total sales for the fiscal year ended March 31, 2011, amounted to $6.4 billion USD.

QR Code® is a registered trademark of DENSO Wave Incorporated.