Optical Measurement Section, NRLM, AIST
Facilities
Facility
- 300 m tunnel for optical measurement
Equipments
- Interferometer for line standardand
- Interferometer for end standard
- Ti: Sapphire laser and its amplifier
300 m tunnel for optical measurement
@This is a 300m long, semi-underground tunnel with a small air turbulence.
It is useful for long distance standard and large scale measurement. The
following instruments are available in the tunnel.
- 50m long moving carriage with interferometric length measurement
- environmental measurement equipments: 53 thermometers, 3 barometer
and 3 humidity meter
- 7 points baseline for geodetic survey
- an interferometer for measuring a small strain of the tunnel
The tunnel is utilized for developments and evaluations of distance/length
measuring instruments such as an optical waveguide distance meter.
Interferometer for line standardand
Line standards up to 2m can be calibrated with an accuracy of 0.1ppm using
this equipment. The equipment consists of an interferometer with a He-Ne
laser source and a moving carriage based on Eppenstein's principle.
Interferometer for end standard
@Gauge blocks up to 250mm can be calibrated with an accuracy of 0.1ppm.
This is a multi-wave interferometer with a mercury lamp. The equipment was
developed by NRLM and Tsugami Corporation. 20-30 equipments of the same
type are used in standard laboratories in the world.
Ti: Sapphire laser and its amplifier
(Explanation text is under construction)
