Little-Known Stories of Masahiro Hara, the Inventor of the QR Code

An Invention Born from Lunchtime Games of Go

In 1994, Masahiro Hara, then an engineer at Denso (now Denso Wave), was working on developing a new code to make inventory management at automotive parts factories more efficient. Conventional barcodes could hold information only in the horizontal direction, and there was a limit to how much data they could store. Facing the challenge of "Could we make a code that holds data in two dimensions, vertically and horizontally?", Hara found his hint in the games of Go he played with colleagues during lunch breaks.

Hara himself has said in interviews that seeing the white and black stones lined up in an orderly way on the Go board gave him the idea that "data could perhaps be represented with a grid pattern of black and white." A Go board is a 19 by 19 grid, and a white or black stone is placed on its 361 intersections. This structure is essentially the same as the module layout of a QR code. The fact that a traditional Japanese board game became the source of inspiration for a technology that changed the world symbolizes how innovation is born from everyday life.

An Obsession with "Readable Even When Dirty"

What Hara valued most in development was "being read reliably even in the harsh environment of a factory." Automotive parts factories are environments where oil stains, metal dust, high temperatures, and vibration occur every day. Barcodes were vulnerable to dirt, and reading errors occurred frequently when even part of a label got dirty.

What was introduced to solve this problem was error correction using the Reed-Solomon code. This function, which at error correction level H can restore up to about 30% of the data (codewords) when it is missing, became the QR code's biggest technical feature. The design lets you choose the error correction level from four levels, L / M / Q / H, so you can use them selectively: at sites where codes get dirty easily, you raise the level to add more redundant data for restoration, and for uses where you want to keep the printed area small, you choose a lower level. The more redundancy you add, the larger the code becomes for the same amount of information, but letting the user choose that balance is what made the code adaptable to harsh environments.

Another obsession was "high-speed reading." On a factory line, parts flow past at high speed, so the scanner needs to recognize the code instantly. The finder patterns (position detection patterns) placed in three corners of a QR code are a device for instantly identifying the position and orientation of the code from any angle. The ratio of the black and white widths in this shape is 1:1:3:1:1, and the developer explains that the development team broke printed materials down into black and white, studied them, and chose the ratio least likely to appear on a printed page. Because the code can be found by looking for this ratio whichever direction the scan line enters from, the position and orientation can be determined at once even if the label is tilted. The developer states that this mechanism allows the code to be read more than 10 times faster than other codes.

The Strategic Decision Not to Exercise Patent Rights

The most important decision in the history of the QR code was that its developer, Denso (now Denso Wave), published the specification and declared that it would keep its patent rights but not exercise them for QR codes that follow the standard. Rather than abandoning the rights, the company chose to keep them while opening up their use. Without this declaration, QR codes would probably not be used around the world as they are today.

In 1999, it was approved as a two-dimensional code under the Japanese Industrial Standards (Nihon Kogyo Kikaku, now Nihon Sangyo Kikaku), and in 2000 it was also adopted as an ISO international standard. Because it became clear that the specification was public and the rights would not be exercised, a situation arose in which anyone could use the code without an application or a license agreement as long as they followed the JIS or ISO standard, and the barrier to adoption dropped dramatically.

In the short term, this policy meant giving up a path to license revenue, but in the long term it pushed the QR code to become a global standard and expanded both Denso Wave's brand value and the market for QR code products (readers and generation software). The strategy of "growing the whole market by opening up a technology rather than keeping it to yourself" also has something in common with the later philosophy of open source software.

The "Rediscovery" in Europe and the US and COVID-19

QR codes had been widely used in Japan since the 2000s, but their adoption in Europe and the US lagged far behind. In the early 2010s, the marketing industry in Europe and the US judged QR codes to be "hard to use" and "uncool," and at one point people even said "QR codes are dead."

The turning point came in 2017, when Apple built QR code reading into the camera app of iOS 11 as a standard feature. Until then, a dedicated app had to be installed, which was a high hurdle for ordinary consumers, but once you could scan just by pointing the camera, the barrier to use dropped all at once.

Then in 2020, the COVID-19 pandemic made the spread of QR codes in Europe and the US decisive. Viewing menus without contact, showing proof of vaccination, carrying out health checks when entering a store. QR codes spread explosively for these uses, and the verdict that "QR codes are dead" was completely overturned. An unexpected event, the pandemic, pushed a technology born in Japan to become a global standard.

"The Future of the QR Code" in the Inventor's Words

In 2014, the QR code development team, including Masahiro Hara, won the "Popular Prize" at the European Patent Office's European Inventor Award. This category is chosen from among the candidates by a public vote, so it was an event in which the social reach of the QR code was recognized internationally.

In an interview published by the developer, Hara looks back and says that it was originally a code made to make production management of automotive parts more efficient. The current reach of a code born for factory inventory management, now used in payments, healthcare, education, entertainment, and even space development, goes far beyond what was imagined at the time of development.

Technology spreads beyond the intentions of the people who made it. The 30-year history of the QR code shows this. A small black and white pattern born in a factory in Aichi Prefecture in 1994 has become, in the 2020s, an essential infrastructure in the daily lives of people around the world. This story teaches us that one engineer's obsession and the courageous decision to open up a technology can change the world.