Natural crystals are known for their five major properties: focus refraction, data storage, information transmission, energy conversion, and energy amplification. Additionally, crystals exhibit notable elasticity, compressive strength, resistance to acids and alkalis, piezoelectric properties, and a high degree of transparency. These attributes have been widely applied in various fields.
As early as 1880, the Curie couple discovered the piezoelectric property of crystals, which is the generation of an electric charge on one end when pressure is applied to the other end. This discovery, however, was not extensively explored at that time.
Piezoelectric Crystals
In 1922, Western scientist W.G. Cady advanced the study of piezoelectric crystals. Building on the Curie couple's work, he observed that when electricity flows through a crystal, it expands and contracts upon stopping the current. Under alternating current, the crystal oscillates at a high, stable rate, a phenomenon later termed "oscillation." When precisely cut to specific dimensions, this oscillation frequency can be accurately controlled. The resulting precisely crafted crystals are known as oscillation chips, heralding a new era.
Quartz resonators, made using crystal properties, are crucial in the wireless electronics industry. Characterized by high stability, sensitivity, and a broad frequency range, these resonators are integral to various devices like transmitters, receivers, and radio measurement instruments. This includes telegraphs, faxes, televisions, radios, and extends to artificial satellites, missiles, supersonic planes, rockets, ships, radars, electronic calculators, quartz watches, and various remote control, tracking, and navigation equipment.
In the 1990s, the advent of micro quartz resonators marked a significant technological leap. These resonators contained extremely thin crystal slices, showcasing the sophistication of this technology. This innovation spurred the miniaturization of electronic products, leading to smaller mobile phones, computers, and simpler television remote controls, with a rapidly growing global demand.
Optical Crystals
Utilizing the high transparency of crystals, numerous optical crystals have been selected for specialized applications. These pure, colorless, and transparent crystals are devoid of internal imperfections like twinning, nodules, inclusions, cotton-like features, fractures, and rutile needles. Leveraging the unique optical properties of crystals, they serve various purposes: from crafting various instrument lenses capable of photographing and observing in ultraviolet light to creating prisms and lenses for spectrometers, quartz filters for solar observation, ultraviolet lamps for sterilization and medical treatment, polarimeter lenses for measuring the concentration and content of optically active substances, to telescope and microscope lenses for observing celestial bodies and microorganisms.
Melted Crystals
Natural crystals, when subjected to high-temperature melting and purification, are termed melted crystals. These crystals exhibit high-temperature resistance and acid-alkali resilience. They are used in the quartz glass industry for producing quartz glass tubes, containers, optical glass, synthetic crystal raw materials, and are extensively applied in electronics, chemical, metallurgical, communication, automotive, machinery manufacturing, medical apparatus, and the instrumentation industry.
Since the establishment of New China, Donghai 105 Mine and Donghai Optical Instrument Factory have developed and processed crystal products according to national needs, making significant contributions to the nation's cutting-edge science.
Synthetic Crystals
Also known as man-made crystals, synthetic crystals are a product of modern high technology, developed in response to the increasing scarcity of natural crystal resources. They are artificially created under specific conditions that mimic those required for the formation of natural crystals. The widely used hydrothermal method for crystal synthesis has led to the production of various colored crystals such as tea, purple, green, yellow-red, and black. Hydrothermally synthesized crystals, apart from exhibiting crystal seeds, regular hexagonal prisms, and pyramids with uneven, step-like crystal faces, share physical, chemical properties, and internal structures with natural crystals, but with significantly fewer impurities and defects. Consequently, synthetic crystals and their products have quickly gained recognition in the industrial market.
In summary, crystals have become inseparably linked with industry, playing a ubiquitous role. With the rapid expansion of industries like television, computer, mobile telephony, and network communication, the use of crystals remains essential. Despite the advancements in these industries, such as televisions evolving from black and white to color, from a
