Abstract: This invention provides a method of detecting sub-ppm lead impurity levels in a below 200 nm transmitting optical calcium flouride crystal. The method includes providing a below 200 nm wavelength transmitting optical flouride crystal having a crystal light transmission path length, providing a 200-210 nm spectrophotometer having a light source for producing a transmission test wavelength in the range 200 to 210 nm and a transmission detector for measuring transmission of the test wavelength, and transmitting the transmission test wavelength in the range of 200 to 210 nm through the below 200 nm wavelength transmitting optical flouride light transmission path length and measuring the transmission of the 200 to 210 nm test wavelength through the path length to provide a lead ppb impurity level measurement less than 500 ppb. The invention provides for improved manufacturing of below 200 nm wavelength optical elements and optical fluoride crystals such as ultralow lead contaminated calcium flouride.

Abstract: The invention provides a method of detecting sub-ppm lead impurity levels in a below 200 nm transmitting optical calcium fluoride crystal. The method includes providing a below 200 nm wavelength transmitting optical calcium fluoride crystal, providing a fluorescence spectrometer having a light source for producing a 200 to 210 nm selectable wavelength incident radiation and a detector for detecting excited luminescence light in the wavelength range of 210-260 nm produced by the incident radiation, exciting a first luminescence area of the crystal with the 200 to 210 nm selectable wavelength incident radiation and detecting with the detector excited 210 to 260 luminescence light produced from the crystal luminescence area by the 200 to 210 incident radiation to provide a lead ppb impurity level measurement less than 100 ppb. The invention provides for improved manufacturing of below 200 nm wavelength optical elements and optical fluoride crystals such as ultralow lead contaminated calcium fluoride.

Abstract: The invention provides a method of detecting sub-ppm lead impurity levels in a below 200 nm transmitting optical calcium fluoride crystal. The method includes providing a below 200 nm wavelength transmitting optical calcium fluoride crystal providing a fluorescence spectrometer having a light source for producing a 200 to 210 nm selectable wavelength incident radiation and a detector for detecting excited luminescence light in the wavelength range of 210-260 nm produced by the incident radiation, exciting a first luminescence area of the crystal with the 200 to 210 nm selectable wavelength incident radiation and detecting with the detector excited 210 to 260 luminescence light produced from the crystal luminescence area by the 200 to 210 incident radiation to provide a lead ppb impurity level measurement less than 100 ppb. The invention provides for improved manufacturing of below 200 nm wavelength optical elements and optical fluoride crystals such as ultralow lead contaminated calcium fluoride.

Abstract: This invention provides a method of detecting sub-ppm lead impurity levels in a below 200 nm transmitting optical calcium flouride crystal. The method includes providing a below 200 nm wavelength transmitting optical flouride crystal having a crystal light transmission path length, providing a 200-210 nm spectrophotometer having a light source for producing a transmission test wavelength in the range 200 to 210 nm and a transmission detector for measuring transmission of the test wavelength, and transmitting the transmission test wavelength in the range of 200 to 210 nm through the below 200 nm wavelength transmitting optical flouride light transmission path length and measuring the transmission of the 200 to 210 nm test wavelength through the path length to provide a lead ppb impurity level measurement less than 500 ppb. The invention provides for improved manufacturing of below 200 nm wavelength optical elements and optical fluoride crystals such as ultralow lead contaminated calcium flouride.