Our product
We supply various kinds of perfect optical sapphire crystals including flat surface , curved surface , spherical surface , multi surface , cylindrical surface , box type , and some other very special style .
We use the Level A raw material which have excellent transmittance (85% , it come up to 93% after make anti-reflective coating) ; high hardness (Mohs 9 which only less than diamond ) ; high purity quotient (the chemical purity is 99.995%) . The Density of our sapphire material is 3.98-4.1g/cm³, and it have below physical properties:
¡ñ Compressive Strength: 21000 kg/ cm²
¡ñ Tensile Strength: 1900kg/ cm²
¡ñ Bending Strength: 4000kg/ cm²
¡ñ Refractive Index: parallel optical axis 1.769, vertical optical axis 1.76
¡ñ IR Transmittance: 83%
¡ñ Melting Point: 2050¡æ
¡ñ Softening Point: 1800¡æ
¡ñ Specific Heat: 0.18cal/g. ¡æ; 25¡æ
¡ñ Expansion Coefficient: parallel optical axis 6.7x10-6/¡æ, vertical optical axis 5.0x10-6/¡æ
¡ñ Heat Conductivity: 0.09cal/sec.cm¡æ; 25¡æ
These crystals are widely used for watch surface , watch case, watch bezel, watch dial , watch movement , mobile lens , camera lens , jewellery , medical equipment , artware , substrate of LED etc .
