Tracing the Roots of Casio at the Toshio Kashio Memorial Museum of Invention

Casio Computer is known for its innovative electronic products like calculators and musical instruments as well as its popular G-Shock brand of digital watches. The founding Kashio family has retained a central role in the company’s operations and development of the devices that constitute Casio’s core businesses.

In April 2023, Casio made waves when it appointed Masuda Yūichi as company president, marking the first time that an individual from outside the founding family was chosen to head the firm. Masuda took over for Kashio Kazuhiro, who stepped to serve as chair of Casio’s board of directors.

Masuda Yūichi, right, shakes hands with Kashio Kazuhiro the eldest son of founding brother Kashio Kazuo, at a press conference on February 27, 2023. (© Casio)

Masuda was part of the original G-Shock project team and has been a driving force in the company’s core watch business. Casio shook up the watch industry in 1974 when founding brother Kashio Toshio (1925–2012) developed the groundbreaking Casiotron.

Over his career, Toshio invented a huge variety of revolutionary electronic devices, including compact calculators and an array of musical instruments, helping Casio become a global electronics leader. His home in the Seijō neighborhood of Setagaya, Tokyo, where he started his career as an inventor, has been converted into a museum that preserves his legacy for future generations. Visitors to the Toshio Kashio Memorial Museum of Invention can trace his life, achievements, and roots of his ideas.

The Toshio Kashio Memorial Museum of Invention in Seijō, Setagaya. The building and its furnishings have an avian motif that reflects Toshio’s love of birds.

A picture in the Casiotron exhibit shows Toshio in his later years.

A Life of Invention

Established in June 1957, Casio Computer built on the achievements of its predecessor Kashio Seisakujo. The firm started out developing and producing Toshio’s revolutionary invention, the 14-A, the world’s first compact, all-electric relay calculator. The success of the 14-A and its successors transformed Casio into an industry leader, and by the late 1960s and early 1970s, the company was synonymous with calculators. From there, Casio began to branch out into other fields, ranging from electronic musical instruments to medical devices. Today, the firm’s G-Shock and other watch lines account for a majority of its sales, but Casio keeps “Computer” as part of its name in recognition of its beginnings.

In fact, the spelling of the company name in Roman letters has origins in calculation. The 14-A was marketed for its speed advantage over competitors, but the four founding brothers–Tadao, Toshio, Kazuo, and Yukio–all agreed that “Kashio” did not convey a sense of speed. They eventually agreed on spelling it Casio, adapted from the constellation Cassiopeia.

The 14-A (center) and programable scientific calculator AL-1 (back left) on display at the Toshio Kashio Memorial Museum of Invention.

With the recent advent of smartphones and personal computers featuring calculator software and spreadsheet programs, the use of physical calculators is on the decline. However, even young people will grasp Toshio’s achievements when told that he was the man who popularized the 10-key numeric keypad.

Calculators before the 14-A used a so-called full keypad, with multiple columns of keys numbered 0–9. Toshio arranged the number keys in a pattern of four lines and three columns, placing the decimal point at the bottom next to the 0 key, for easier one-handed operation. Although some adding machines in the United States already used versions of the numerical keypad, Casio’s calculators brough the arrangement into the mainstream, and today it continues to be used on computer keyboards, shop registers, and smartphone calculator apps.

The 14-A’s modern numeric keypad.

Rival of the 14-A, Sharp’s 1964 Compet electronic desktop calculator featured a full keypad with columns of 10 keys. (© Jiji/Sharp)

From “Ring Pipe” to Calculators

Toshio was born in Tokyo in 1925. As an elementary school student he was inspired to become an inventor after reading a biography of Thomas Edison. He proceeded to study electrical engineering, and in 1940, at the tender age of 15, he went to work for the Ministry of Communications, the forerunner of today’s Ministry of Internal Affairs and Communications. Following the end of World War II, he joined his older brother Tadao’s small manufacturing company.

The company’s first hit product was the yubiwa paipu, a finger ring that doubled as a cigarette holder, which it released in 1946. In the shortages of the postwar period, people commonly smoke unfiltered cigarettes, puffing down to the very end and burning their fingers in the process. This gave Toshio the idea for the simple product, which quickly became a hit as it enabled people to make the most of their limited smokes while also freeing their hands for other tasks. The company sold as many of the rings as it could make, the profits of which allowed the small family business to stop doing subcontract work and start investing in its own operation.

As part of the Casio founding family, Toshio is often thought of as a specialist in electronics. But he himself insisted that any new creation can only be considered an invention if it comes in handy for life, an idea that would guide him over his long career. Over his lifetime, Toshio acquired 313 patents for his inventions, including some jointly held, ranging from electronics to bowling, a favorite hobby of his.

The Kashio Seisakujo pipe ring. Toshio was an inventor who focused on the daily lives of common people.

A great change in Toshio’s career came in 1949 when he attended an exhibition of electric office equipment in Tokyo’s Ginza. At the time, most Japanese businesses and households still relied on the abacus to tally accounts. At the exhibit, Toshio saw for the first time electric calculating machines used overseas. The devices worked by using electric motors to spin gears. They were big, noisy machines that cost as much as a new car, but they were considered “cutting edge” technology and subsequently drew the attention of hordes of attendees.

Toshio succeeded in shrinking the size of the calculating apparatus of his 14-A by using relays to create electrical circuits, resulting in a desk-sized calculator. Not only did the device calculate faster, but it was quieter to operate, a feature that won it accolades. Casio’s later releases also went on to be hits, such as the 14-B equipped with a square root function and the AL-1 programmable scientific calculator, setting a track for continued success.

Casio’s AL-1, the original scientific and technical calculator, became a long-selling hit.

A Life of Invention in Brotherhood

With such successes under his belt, Toshio might have come to overshadow his brothers, but this was not the case. Rewording Edison’s famous quote, Toshio proclaimed that invention was “One percent inspiration, forty-nine percent perspiration, and fifty percent luck.” To that he added, “My luck has been my brothers,” showing the great faith he held in them.

While Toshio was known as an ideas man, he was not as skilled at deciding which products to make and how to market them. His oldest brother Tadao guided the company, while Kazuo, the third brother, had the sales skills to open new markets. Finally, youngest brother Yukio was the engineer who could take Toshio’s inventions and turn them into mass-produced products. It was only through the combined strengths of these four brothers that Toshio’s ideas reached the world.

The four Kashio brothers around the time of Casio’s founding. From Left: Toshio, Kazuo, Tadao, and Yukio. (© Casio Computers)

The hand-drawn circuit schematic for the 14-A. Toshio’s main job was to put ideas into drawings, and his brothers handled the rest.

Sharp released a transistor-based electronic calculator in 1964, and rival Canon soon followed. Casio began to lag behind due to Toshio’s insistence on using relays, putting the business in danger.

When the brothers finally decided to change course and enter the electronic calculator market, Tadao set to raising funds and Kazuo searched for new sales channels. Yukio set up a production system, and in just four months, the first Casio electronic calculator, the 001, hit the market.

The first Casio electronic calculator, the 001.

As demand for desktop calculators grew, some 50 companies joined the fray in what became known in Japan as the “calculator wars.” Casio would eventually come out on top in the battle for market dominance when Toshio developed the first personal calculator, the Casio Mini.

Aiming at small shops and private households, the device was able to calculate up to 12 digits. The company planned to price the calculator at a third of what rivals were charging for their products. There was some pushback against this within the company over concerns that the item would flop, but Kazuo believed it would appeal to individual customers and optimistically predicted sales of 100,000 units a month.

In August of 1972, the Mini hit the market with the price tag of ¥12,800. It was an instant hit. Casio sold over one million units in less than a year and would become indelibly associated with calculators.

The Casio Mini took Japan by storm.

Hit products kept coming, like the Casio Minicard (right) and the credit-card sized SL-800 calculator.

New Avenues

The next thing Toshio turned his attention to was developing digital wrist watches, which were still in their infancy. He applied his knowhow with calculators to the task, saying that “keeping time is just adding one second after another.”

Digital wrist watches at the time required wearers to manually adjust the date at the end of every month less than 31 days. Toshio developed a fully automatic calendar function that featured on Casio’s first watch, the Casiotron. The time piece quickly became a hit when it debuted in 1974. Following on this success, Casio released a string of watches boasting new and innovative functions like a built-in calculator and the ability to store names and phone numbers. These eventually led to Casio launching its G-Shock line in 1983.

The two watches on the right are Casiotrons, while on the left is the X-1 from 1976, the first to be equipped with functions like a world clock and stopwatch.

The G-Shock section at the museum displays a valuable first-generation model alongside other popular types.

The next field Toshio branched into was electronic musical instruments, which he did out of a desire to allow more people to enjoy the pleasure of playing music. Using his unique way of seeing the world, he created a “consonant-vowel synthesis” system that mimicked the sounds of different musical instruments.

For example, a piano makes a different sound when the keys are struck and released compared to when they are held down. Toshio compared these to the consonant and vowel sounds of human speech, where the initial strike of a note is a “consonant” and the sustained sound is a “vowel,” and he believed that combining the two would reproduce all types of sounds.

In January of 1980, Casio released its Casiotone 201, an electronic keyboard equipped with 29 reproduced instruments ranging from piano and organ to harp and koto, and even wind instruments like the trumpet and flute. It was modestly priced at ¥97,000, and even today’s acoustic experts say it achieved unbelievable performance in natural sound reproduction given the low-performance circuitry of the time. That was the start of Casio’s many contributions to the world of music.

The Casiotone 201, with 49 keys and internal speakers, drew fans for its compact size and simplicity.

In a testament to Toshio’s attention to detail in music, he had the wall behind this audio set lined with marble for better acoustics.

A Life Dedicated to Invention

The Toshio Kashio Memorial Museum of Invention brings visitors in contact with the sources of Toshio’s creativity, like the study where he would contemplate ideas and various personal effects he loved. For Toshio, invention was not a way to respond to someone’s needs, it was a way to reveal as-yet undiscovered needs. He felt that if a core product can continue to surprise people, it will eventually become something indispensable throughout the world, evolving and improving as more people use it. This process is what he saw as the true value of invention.

Toshio’s many sayings are displayed in a corridor alongside pictures of the inventor.

Toshio’s hand drawn electronic music instrument schematics. He continued to invent new devices into his later years, drawing his plans with only paper, pen, and ruler.

Toshio was fond of saying, “Yesterday, I was an idiot.” He kept his mind working every day, coming up with new ideas that he had failed to see the day before. A former colleague who knew him in his later years chuckles at the phrase, which Toshio used to mean a person is smarter today than they were the day before. “He’d ask if we’d worked hard enough to make that claim,” he says. “But everyone would struggle to answer.” He goes on to reflect that even into his eighties, Toshio remained focused on his work. “He’d be up all hours of the night. His was truly a life given to invention.” Even after Toshio left his post to become chairman, he kept his office at the Hamura R&D Center rather than at the company’s head office.

A display of winning entries in the annual Kashio Toshio Invention Idea Contest for elementary school students.

A portion of the museum’s garden is open to the public.

Toshio Kashio Memorial Museum of Invention

• Address: 4-19-10 Seijō, Setagaya, Tokyo
• By reservation only. Please check the official website for details (Japanese only).
• Entry is free.
• Getting there: 15 minutes’ walk from Seijōgakuen-mae Station on the Odakyū Odawara line.

(Originally published in Japanese. All photos © Nippon.com except where noted.)