What are Sapphire Windows?
Sapphire Optics is a synthetically grown super hard material that is extremely durable and resistant to scratches. It second only to diamond in terms of its strength. Sapphire windows can withstand more than what quartz and conventional glass can, and at a fraction of the thickness. Sapphire crystals are “grown” in extremely hot ovens. The large, cylindrical boules are cut into sapphire rods, which are then sliced into thin discs, ground, and polished.
Uses of Sapphire Windows
Sapphire windows are used when sapphire’s unique properties – high strength, high scratch resistance, wide optical transmission band, extremely high melt temperature, high thermal conductivity, high electrical resistance and chemical inertness – are required.
There are many commercial uses for sapphire. Among the most commonly known are the sapphire display windows that are used to protect the phones’ optics. Newer iPhones use sapphire windows because their fracture toughness is roughly four times greater than Gorilla Glass, which is just strengthened conventional glass. Prior to the smartphone revolution, most consumers’ consumers’ experience of sapphire came from the displays used in most high-end watches.
Optics, Wafers and Crystals
A variety of Optics, wafers and crystals substrates are offered.. Optics products includes: blanks, lenses, windows, prisms and optics made from sapphires, optical glass materials, fluoride crystals and other optical materials., various type of filters for lasers, lighting and biochemical applications and the optical components for IPL equipments. Shalom EO also offers the SAW wafers and substrates made from piezo-electric crystals like LT, LN and quartz, and substrates made from crystals like MgO, GGG, SrTiO3, ect. . The customized optical components for your special applications are available.
Results are presented on the preliminary evaluation of the pixellated NaI(Tl) crystal arrays for use in high-resolution small field-of-view gamma cameras. A prototype detector was developed using the pixellated NaI(Tl) arrays attached to a 5″ diameter position-sensitive photomultiplier tube (PSPMT). Two 5.3 cm square pixellated arrays from Saint-Gobain with pixel sizes of 1/spl times/1/spl times/6 mm and 2/spl times/2/spl times/6 mm were tested. A conventional charge division readout using a resistive chain was used with the PSPMT. The detector was tested using a uniform flood source and a /spl sim/0.8 mm diameter collimated Tc-99m source. The collimated source was scanned over both crystal arrays. The performance characteristics including spatial resolution, energy resolution and the ability to resolve the pixellated crystal elements were determined. The response of the pixellated detector was also measured. With the conventional resistive-chain readout the individual pixels were well resolved for the 2 mm pixellated crystal array but not for the 1 mm pixellated crystal array from the images of a uniform flood source. An average FWHM of 1.4 mm was obtained with a 0.8 mm diameter pencil-beam over the active crystal area for both crystal arrays. The energy resolutions from the individual pixels were 10.8% and 10.0% at 140-keV photon energy for the 1 mm and 2 mm pixellated crystals, respectively. Our study indicates that using conventional resistive-chain readout, a compact detector comprised of a pixellated NaI(Tl) crystal array and a 5″ diameter PSPMT at best can achieve a spatial resolution of /spl sim/1.1 mm. We conclude that the use of pixellated crystal arrays with /spl sim/1.5 mm pixel element is likely to be an optimal choice for the combination of this PSPMT with resistive chain readout technology for development of high resolution small field-of-view gamma cameras.