Holmium Oxide Glass Wavelength Standards

Area of Science:

• Spectroscopy and Metrology
• Materials Science

Background:

• Holmium oxide glass has been a trusted wavelength standard for over 40 years.
• These standards demonstrate minimal spectral variation across different batches and manufacturers.
• The National Institute of Standards and Technology (NIST) has a long history of certifying these samples.

Purpose of the Study:

• To evaluate the long-term stability and reliability of holmium oxide glass as a wavelength standard.
• To determine if continued recertification by NIST is necessary given the material's performance.
• To inform users about updated traceability procedures for holmium oxide glass standards.

Main Methods:

• Analysis of historical spectral data from NIST-certified holmium oxide glass samples.
• Review of NIST's extensive experience and data on holmium oxide glass stability.
• Assessment of the material's robustness against environmental factors like temperature and humidity.

Main Results:

• Insignificant spectral variation observed in holmium oxide glass standards over decades.
• No recorded instances of spectral shifts in certified bands.
• Holmium oxide glass is robust and insensitive to normal temperature and humidity fluctuations.

Conclusions:

• NIST will no longer recommend the recertification of holmium oxide glass wavelength standards.
• Traceability can be established through suppliers or end-users, reducing the need for NIST involvement.
• The long-term stability and reliability of holmium oxide glass justify this change in NIST's recommendation.