Dimensional Measurements Laser Measurements Technical Contact: Jack Stone Tel: 301/975-5638 E-mail: jack.stone@nist.gov Do not ship instruments or standards to the mailing address listed below. Contact the technical staff for the shipping address. Mailing Address: National Institute of Standards and Technology 100 Bureau Drive, Stop 8211 Gaithersburg, MD 20899-8211 Service ID Number | Description of Services | Fee ($) | 14510S | Laser Frequency/Wavelength, Full Calibration | 2505 | 14511S | Quick Check of Frequency/Wavelength at Laboratory Conditions | 1331 | Fees are subject to change without notice. back to top | back to index of dimensional measurements The frequency (or, equivalently, the vacuum wavelength) of a red He-Ne laser is determined by comparison to an iodine-stabilized He-Ne laser. The attainable accuracy of this technique is ultimately limited by the uncertainty in the wavelength of the iodine stabilized laser. The relative standard uncertainty of the laser vacuum wavelength at NIST is 5 10-11 . The relative expanded uncertainty is 1 10-10 . The relative expanded uncertainty can be reduced to 5 10-11 on special requests. As a practical matter, however, the uncertainty of a comparison is usually determined by the limited reproducibility of the laser under test. back to top | back to index of dimensional measurements back to top | back to index of dimensional measurements Date created: 06/30/1999 Last updated: 01/17/2008 |