Abstract: The high-purity alkaline earth halide crystals, especially CaF2, BaF2 or MgF2 crystals, have a diffuse scatter distribution function value of less than 7×10?7, an RMS uniformity of refractive index of less than 15×10?8 after subtraction of Zernike coefficients and an RMS value of birefringence in the (111) direction of less than 0.2 nm/cm. Preferably the crystals exhibit a loss coefficient of less than 5×10?4 cm?1 after irradiation with 10×109 laser pulses with an energy density of 10 mJ/cm2 at a wavelength of 193 nm. Also they have RMS birefringence in the (100) direction or the (111) direction that is less than 0.35 nm/cm.

Abstract: A method for producing high-purity, large-volume monocrystals that are especially radiation-resistant and have low intrinsic birefringence. From a melt of crystalline raw material, with controlled cooling and solidification, a crystal is generated. As the crystalline raw material, shards and/or waste from already-grown crystals is used, and the re-used raw material 1) upon visual observation in daylight has no color; and 2) upon illumination with a white-light lamp in a darkroom a) has no or at maximum a just barely perceivable reddish and/or bluish fluorescence; and b) has no or at maximum a just barely perceivable diffuse scattering; and c) has no or only slight discrete scattering of at maximum two visually perceivable scattering centers per dm3. In this way, crystals can be obtained which after tempering have a BSDF value of <7×10?7, an RMS homogeneity after the subtraction of 36 Zernike coefficients of <15×10?8, an SDR-RMS value in the 111 direction of <0.2 nm/cm.

Abstract: A method for producing high-purity, large-volume monocrystals that are especially radiation-resistant and have low intrinsic birefringence. From a melt of crystalline raw material, with controlled cooling and solidification, a crystal is generated. As the crystalline raw material, shards and/or waste from already-grown crystals is used, and the re-used raw material 1) upon visual observation in daylight has no color; and 2) upon illumination with a white-light lamp in a darkroom a) has no or at maximum a just barely perceivable reddish and/or bluish fluorescence; and b) has no or at maximum a just barely perceivable diffuse scattering; and c) has no or only slight discrete scattering of at maximum two visually perceivable scattering centers per dm3. In this way, crystals can be obtained which after tempering have a BSDF value of <7×10?7, an RMS homogeneity after the subtraction of 36 Zernike coefficients of <15×10?8, an SDR-RMS value in the 111 direction of <0.2 nm/cm.