About Rion

Rion's acoustics and vibration technologies support businesses and lifestyles in various fields.

Print This Page

Font Size:

  • S
  • M
  • L


External view of the no.1 plant at Kobayasi-riken

Rion was founded in 1944 under the name of Kobayasi-riken Co.,Ltd. to commercialize the products based on the results of research activities by the Kobayasi Institute of Physical Research, a foundation dedicated to the study of physics and acoustics. Rion started to manufacture crystal elements for acoustic equipments and their applied products, as the first manufacture of such products in Japan.

After that, Kobayasi-riken started to manufacture and sell the first hearing instruments in Japan with aiming to solve the stress for hearing-impaired people and to make their speech communication better. "Rionet" hearing instruments, as the brand name of Rion hearing instruments, have been familiar and popular and keep on taking top market share in Japan. It also spreads such network worldwide.

In 1960, Kobayasi-riken changed its name to Rion, which derived from Ri of Rigaku meaning science + On from Onkyogaku meaning acoustics.

In addition to hearing instruments, Rion provides wide range of products to various fields. Medical instruments typified by audiometers are used in the field of otolaryngology. Sound and vibration measuring instruments are demanded by government agencies and industries to protect environment and quality in manufacturing. Particle counters are indispensable for cleanliness management of semiconductors, pharmaceuticals, and precision equipment. Not only domestic but also international, our products get good evaluations from customers.

As mentioned above, Rion has tried to keep the technologies and to challenge for new technologies. Rion is proud of its role for promoting social welfare, for contributing to safe and comfortable life and to technological innovation, and will strive for achieving its mission.


1944 Kobayasi-riken Co., Ltd. is established.
1946 Rochelle salt piezoelectric phono cartridge and microphone are introduced.
1948 The first hearing instrument in Japan (H-501) is introduced.
1950 Hearing instruments is granted as meeting requirements 01 the Act on Welfare of Physically Disabled Persons.
1952 RION's first Audiometer (A-1002) is introduced.
1954 Osaka Service Station (current West-Japan Office) is opened.
1955 RION's first Sound level meter (N-1101) is introduced.
1956 Transistorized hearing instrument (H-530) is introduced.
Audiometric Test Room (AT-2) is introduced.
Viscotester (RV-1501) is introduced.
1959 Nystagmographs (NY-2301) is introduced.
1960 Rion Metal Engineering Co., Ltd. (currently a consolidated subsidiary) is established.
Corporate name is renamed to RION Co., Ltd.
1961 Rionet Center is opened.
1962 Disc-type Sound Reproduction Device (RR-01) is introduced.
1963 Sendai Branch (current Sendai Office) is opened.
1964 Behind-the-ear hearing instrument (HA-07) is introduced.
Piezoelectric Igniter (PE-01) is introduced.
1965 Vibration Meter (VM-01) is introduced.
1969 Tohoku Rion Co., Ltd. (completion of stopping its business on Mar. 2010) is established.
EEG adding device (AR-03) is introduced.
1970 Komiyadenki Co., Ltd. is acquired as a subsidiary of Rion (currently a consolidated subsidiary and renamed to Kyushu Rion Co., Ltd).
The first digital sound level meter in the world (NA-10) is introduced.
1971 Rion hearing instrument (HA-27 series) receives a Good Design Award in Japan, as first for hearing instruments.
1972 Nagoya Branch (current Tokai Office) is opened.
1974 Hiroshima Branch (closed in May 2002, merged with the current West-Japan Office) is opened.
Rion sound level meter got the type approval of the Measurement Act, as first for sound level meters.
1977 Airborne Particle Counter (KC-01) is introduced.
1979 Rion Electronic Industries Co., Ltd. in Taiwan, R.O.C., (sold on Oct. 2013) is established.
1980 Seismometer (SM-10) is introduced.
1981 The first transistorized Anemometers in the world (AM-02,AM-03) are introduced.
The first hearing instrument with Automatic Noise Suppression (ANS) in the world (HA-39AS) is introduced.
1983 The first middle ear implant in the world is developed.
The first bone conduction hearing instrument spectacles with wireless CROS (HE-72) is introduced.
1984 Custom-made in-the-ear hearing instrument (HI-02) is introduced.
The first drip-proof BTE hearing instrument in the world (HB-35) is introduced.
The first Liquid-borne particle counter manufactured in Japan (KL-01) is introduced.
1986 The first waterproof BTE hearing instrument in the world (HB-35PT) is introduced.
The first 1/N Realtime Analyzer in the world (SA-26) is introduced.
1991 The first Digital hearing instrument in the world (HD-10) is introduced.
1993 IS09001 certificate for noise meters is approved.
1995 IS09001 certificate for all products other than noise meters is approved.
1996 Stock is listed on the OTC market.
RI Inc. (current non-consolidated company) is established.
The first hearing instrument with Either-way Circuit (battery can be inserted without caring for +- side) in the world (HB-55S) is introduced.
1997 Kokusai Hochouki Co., Ltd. is acquired as a subsidiary of Rion (currently named Kanto Rion Co., Ltd. a consolidated subsidiary)
1998 CE certificate (93/42/EEC) is approved.
1999 ISO14001 certificate is approved.
2000 Stock is listed on the Tokyo Stock Exchange 2nd Section.
2002 Rion Service Center Co., Ltd. (currently a consolidated subsidiary) is established.
Rion Techno Co., Ltd. (currently a consolidated subsidiary) is extablished.
European representative office in the Netherlands is opened.
2003 ISO13485 certificate is approved.
2004 The first automatic shell manufacturing system for custom-made hearing instrument,"Yumejikoubou", is started its operation.
2005 The first custom-made waterproof digital hearing instrument in the world (HI-G4WE) is introduced.
Fukuoka Hearing Aid Center (current non-consolidated company) is acquired by Kyushu Rion Ltd. to be a subsidiary.
2006 Rion Measuring Instruments Sales Co., Ltd. is established (completion of stopping its business on Nov. 2012)
Tokai Rion Co., Ltd. is established (current consolidated subsidiary)
Total number of Hearing Instrument shipments reached 6 million
Total quantity of hearing instrument sales is passed 6 million.
2008 Tokyo Office is opened.
2009 Hear Link (current Tokyo Rionet Sales Co., Ltd., a non-consolidated company) is acquired, to be a subsidiary.
2010 China Representative Office is opened in China (closed in Mar. 2013)
The first handheld OAE screener manufactured in Japan (ER-60) is introduced.
2011 Stock is listed on the Tokyo Stock Exchange 1st Section.
2012 East-Japan Office is opened. (closed in Mar. 2016)
Shanghai Rion Retail Co., Ltd. (current non-consolidated company) is opened in China.
2017 The world's first cartilage conduction hearing instrument is marketed.
2020 The world’s first wireless rechargeable system for hearing instrument is marketed.
The world’s first completely wireless audiometer is marketed.
2022 Moved to Prime Market in Tokyo Stock Exchange.
Norsonic AS is acquired as a subsidiary of Rion (currently a consolidated subsidiary).