Method for determination of the radiation stability of crystals

US6603547B2 · kind B2 · utility

Assignee

• Schott Glas · DE

Inventors

• Ewald Moersen · Mainz, DE
• Burkhard Speit · Mainz, DE
• Lorenz Strenge · Ingelheim am Rhein, DE
• Joerg Kandler · Cospeda, DE

Key dates

• Filing date: Oct 11, 2001
• Grant date: Aug 5, 2003
• Expiry date: Jan 15, 2022

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N21/31
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The method for determining radiation stability of a crystal to radiation of a working wavelength to be employed in a subsequent application includes taking a first absorption spectrum (A) of a cleaved piece of the crystal with a given thickness (D) over a predetermined wavelength range from a first wavelength (&lgr;1) to a second wavelength (&lgr;2) by means of a spectrophotometer. Then the cleaved piece of the crystal is irradiated with an energetic radiation source so as to form all theoretically possible color centers (saturation). After the irradiating a second absorption spectrum (B) of the cleaved piece of crystal is taken over the same predetermined wavelength range. Then a surface integral of a difference spectrum of the first absorption spectrum and the second absorption spectrum over the predetermined wavelength range is formed and divided by the thickness (D) to obtain a scaled surface integral value. The absorption coefficient &Dgr;k at the working wavelength for the subsequent application is then obtained preferably from the scaled surface integral value for the damage induced by the energetic radiation and a calibration curve relating the absorption coefficient at the…