Skip to main content

On track to a brighter future

The History of Wired Communication

Anritsu for Fiber Optics: Ushering in the Age of Optical Communications

Fiber optic technology developed to handle a rapid increase in telephone use

The 1964 Tokyo Olympics were a symbolic recovery project after World War II. Various forms of national development took place as a result, including a rapid increase in Japan’s number of landline phones between then and the 1970s. As telephones became commonplace in ordinary households throughout Japan, telecommunication traffic grew continuously, and Japan’s telephone operator had to expand their facilities quickly to meet the demand.
Nippon Telegraph and Telephone Public Corporation, the precursor to Japan’s largest telecommunications company (NTT), studied two methods of expanding the capacity of their facilities: milli-waves (wireless communication) and fiber optics (wired communication). Fiber optics was chosen as the new transmission method and the first optical telecommunication test plan was devised in 1977. And so began the age of transmitting information by fiber optics. Anritsu began supplying measuring instruments for optical communications in the same year, and has played a key role in the advancement of fiber optic technology ever since, developing a wide range of measuring instruments.

  • Rotary-dial telephoneRotary-dial telephone
  • Measuring instrument for optical communication testingMeasuring instrument for optical communication testing

Breakthroughs from Anritsu

Breakthroughs from Anritsu

Breakthroughs from Anritsu: Proving the merits of fiber optics

In cutting-edge technology fields, measurement technology needs to be created before developing systems, and it is not uncommon for the measurement technology to bring breakthroughs for the system development itself. Anritsu’s measuring instruments brought one such breakthrough in the development of optical fiber-based signal transmission.
One merit of optical fiber-based transmission is the ability to transfer information stably without losing the signal, but at that time, this was just a theoretical supposition and had not been proven.
Anritsu was the one to finally prove it. We proved that minimal loss occurred by developing electrical power measurement technology for optical fibers at long wavelength ranges (above 1μm, particularly the 1.3 and 1.55μm bands), an area we had been studying at the time. This accelerated the adoption of optical fiber-based transmission methods, laying the foundation for today’s information-based society.

Breakthroughs from Anritsu: The world’s first optical time domain reflectometer

Another breakthrough from Anritsu was the world’s first optical time domain reflectometer to be put to practical use. Fiber optic networks have been set up around the world to handle the increase in telecommunication traffic, but they are not without problems. Optical fibers can bend or break due to various causes, resulting in communication problems. In order to fix the fibers, repair workers need to find the problem area – and it was Anritsu who enabled them to do that. We developed a device called an optical time domain reflectometer, which measures a light phenomenon called backscattering. Backscattering is light that reflects backward from the light traveling along the optical fibers. It is a way to measure the quality of optical fibers, as the position and degree of backscattering indicate the signal loss that is occurring. Anritsu realized that a device measuring backscattering would enable workers to find damaged areas of the optical fibers. We began developing technology for this purpose and succeeded in 1980. Our device for measuring backscattering was the world’s first device for detecting faults in optical fibers, and is now used in optical time domain reflectometers that cover all of the necessary functions for optical fiber measurement including a light source and optical power meter. The device injects a test pulse along optical fibers that can be 100km long and measures points of breakage or discontinuity to determine where communication faults are occurring. This new innovation has improved the quality of fiber optic communication.

  • Optical time domain reflectometerOptical time domain reflectometer

Contributing to the global spread of fiber optic communication

(White Paper: Information and Communications in Japan 1985, Ministry of Internal Affairs and Communications)

In 1985, a fiber optic network was completed throughout all of Japan’s main islands, from Hokkaido to Kyushu, forming the infrastructure of the fiber optic network that Japan uses today. Fiber optic communication is also being increasingly adopted worldwide, resulting in a growing demand for measuring instruments – a demand that Anritsu is filling. Our optical measuring instruments have been adopted worldwide, including at Bell Laboratories in the US, the world’s most prominent information and communications research institute at the time we invented our optical time domain reflectometer. The representatives were amazed to see how our device measured backscattering in field testing and decided to start using it themselves. Our optical time domain reflectometer took the American market by storm, selling so many items that our production facilities could not keep up with the demand. It was also adopted in many European countries including the UK, Germany, Sweden and Italy. Anritsu’s optical time domain reflectometers have crossed oceans and helped to build fiber optic networks worldwide.

Anritsu has spearheaded many new innovations in fiber optic measuring instruments, from downsizing of optical time domain reflectometers to optical power meters that measure light intensity and optical spectrum analyzers that enable evaluation of characteristics of optical parts. Our presence in fiber optics since the dawn of this technology has made us synonymous with fiber optic technology. The attitude behind our success is best summed up by one of the engineers who worked on the development of our optical time domain reflectometer: “When you develop measurement devices that the world has never seen before, nobody can provide parts for them. We had to develop everything ourselves. It was one struggle after another, but we never gave up, and in the end fiber optic networks spread as a result of our work.” This determination has been the driving force of our role in the advancement of fiber optics.

  • TV commercialTV commercial
  • Optical power meter ML93AOptical power meter ML93A
  • Optical spectrum analyzer MS96AOptical spectrum analyzer MS96A

Semiconductor lasers: the beginning of optical technology

Anritsu began developing optical technology as early as 1967. Gas lasers had begun to spread in those days, but Anritsu foresaw that semiconductor lasers would be a key technology for fiber optic communication. We began fundamental research on semiconductor lasers and just as we predicted, these became a key device for instruments such as optical power meters and optical time domain reflectometers.

Semiconductor lasersSemiconductor lasers

How we made it possible to measure backscattering

Backscattering is a factor for measuring the quality of optical fibers. We faced one difficulty after another as we worked to develop technology to measure it. Backscattering occurs at a very low level, which made it impossible to detect at first. Our engineers tried one measure after another and finally succeeded in developing technology that could amplify the faint light that was received. This made it possible to develop the optical time domain reflectometer for practical applications.

Contributing to optical fiber production with a laser outer diameter measuring instrument

Not only did Anritsu’s optical time domain reflectometer play a role in the building of fiber optic networks, we also contribute to the production of optical fibers with our laser outer diameter measuring instrument. Developed in 1974, this instrument is used to create optical fibers with a uniform diameter. At that time, the diameters of optical fibers generally had a standard deviation as large as 20μ (microns), causing the transmission properties to fluctuate. Our laser outer diameter measuring instrument achieved a smaller variation than any other device in the world – just ±5μ – and was adopted by optical fiber manufacturers worldwide. It would not be an overstatement to say that Anritsu’s laser outer diameter measuring instrument made optical fiber production possible.

Laser outer diameter measuring instrumentLaser outer diameter measuring instrument

The only optical measuring instrument that can measure submarine fiber optic cables

Submarine fiber optic cables are laid under the sea. They are used to expand networks across regions separated by water, making them an important part of international communications infrastructure. Anritsu is currently the only company to supply a measurement instrument for submarine fiber optic cables. The instrument is called a coherent OTDR and can detect faults in ultra-long-distance submarine fiber optic cables up to 12,000km long.

Coherent OTDR MW90010ACoherent OTDR MW90010A

Download our booklets

Подтвердите вашу страну ниже, чтобы отобразить местные события, контактные данные и специальные предложения.