|Manufactured by||Hitachi, Toshiba, Tokyo Electron Devices, etc.|
|Owner||The Institute of Statistical Mathematics (ISM)|
|Location of historical materials||Basement Floor 1, ISM, 10-3 Midori-cho, Tachikawa-shi, Tokyo 190-8562 Japan.|
|Visitor information||Open to the public (Reservation required)|
|Contact||Administration Planning and Coordination Section, ISM Tel.+81-50-5533-8580
Those devices are for the high speed generation of physical random numbers which strictly match the statistics theories. The Institute of Statistical Mathematics (ISM) has been producing them for years, for the various usages with the available technologies of the period.
This collection starts from the manual random number generator used up to 1950s. Those are the coins with printed numbers --- a sampler picked one from a bag, read the number and put back --- repeating the process patiently eventually he obtain a set of random numbers to be used for a simulation. Afterwards the electrical devices were introduced for the purpose. The early device made in 1956 is a tube containing radio-active material which made random radiations to be counted as random numbers. As time advances new types of generators were invented and used: diode-noise type, thermal noise type, etc. The thermal noise type is the ISM original in which the noise waveform is AD converted. This forms a bit pattern to be used for random numbers through shuffling. Also there are generators for various types of host computers: for a peripheral device of a main-frame computer, an extension card for a PC, USB device type for an easy attachment, etc. The latest model can generate a stream of random numbers at 640 Mbyte/second. Another generator was used to make the random number tables of the Japanese industrial standard.
To generate physical random numbers of the theoretical correctness the high-speed, precise instrumental technology is required. This collection also exhibits the advancement of electronics technology for half a century. This is a special collection of ISM because no other institute in Japan could virtually produce them.