Scientific and technological progress has accelerated the development of medical care. CT (Computed Tomography) is a computer tomography camera with short scanning time and clear images. Accurate, fast and convenient, with clear imaging characteristics, chest CT examination has become a powerful tool for screening and diagnosis and treatment.

The CT machine consists of an X-ray tomography device and a computer system. The former is mainly composed of a generator that generates X-ray beams and a computer system.CT tube, and detectors for receiving and detecting X-rays; the latter mainly includes data acquisition systems, central processing systems, tape drives, operating consoles, etc. CT uses X-ray beams to scan a certain thickness of the inspection site, which is subjected to penetration by the detector. After the X-rays are converted into visible light, they are converted into electrical signals by photoelectric converters, and then converted into digital signals by analog\/digital converters, which are input into the computer for data processing and image reconstruction, forming CT.

CT tubeAs one of the central components of CT equipment, it is a high-value consumable with high technical barriers. Its performance directly affects the inspection effect and service life of CT inspection. CT tube is technically difficult and involves many scientific fields. The process is complex and the manufacturing cost is high. In complex CT equipment, the CT tube is more prone to damage and failure with the increase of exposure times. With the development of technology and the diversification of clinical needs, the research and development of CT equipment is constantly changing. CT, wide-cone CT, dual-source CT, dual-energy CT, etc., also put forward higher requirements for CT tube. Dosage requirements, on the other hand, require longer tube life and lower cost.

The CT tube is actually a high-vacuum cathode ray 2-pole tube capable of generating X-rays. The cathode is a filament that emits electrons, and the anode is a target that is bombarded by electrons. The cathode filament is heated by a 12V current and generates free electrons At this time, when 40-150KV high voltage is applied to the cathode and anode, the potential difference increases suddenly. Driven by the high voltage and strong electric field, the free electron beam in an active state hits the anode molybdenum-based tungsten target at high speed from the cathode, and generates energy Converted, about 1 percent of the electrical energy constitutes the X-ray, which is emitted by the window; 99 percent is converted into thermal energy, which is distributed by the cooling system.

This means that the CT tube needs to have a higher heat capacity. Generally, the higher the heat capacity, the more heat it can carry, the longer the continuous exposure time, and the longer the service life of the corresponding tube. The improvement of heat capacity is about The requirements for tube material, anode rotation structure, etc. are also higher. The heat dissipation rate of the anode target material is also high, and the high heat dissipation rate can effectively prolong the scanning time, but as the anode speed becomes higher and higher, it is getting closer and closer to the physical limit. , It is very difficult to continue to increase the speed; on the other hand, the increase of the speed means that the shorter the time the electron beam stays at a certain point, the greater the heat received by the target disk, that is, the greater the power, but the bearing is faced with greater challenges, and the heat generated Higher, wear more, but also increase noise.

CT examination is radioactive, and the amount of radiation varies in different parts. The dose, time, and interval of exposure affect the amount of radiation. The interval between the examinee and the CT equipment cannot be adjusted, but it can reduce the dose and time of ray mapping during CT examination. CT scanning speed The faster, the shorter the exposure time to radiation; the lower the radiation dose, the less radiation.

Earlier, the domestic CT market was monopolized by foreign brands such as Philips, Siemens, and GE. Zhuhai Ruineng Medical completed the localization of CT tubes for the first time, achieving a historic breakthrough in "Made in China". The 12th Institute of Electronic Science and Technology, Shanghai United Imaging, Kunshan Yiyuan and other cutting-edge companies have their own strengths, and slowly opened up a new scene of domestic CT tubes.

The diversified competition of domestic and foreign enterprises has accelerated the multi-point research and development of CT tube, and the results have been remarkable. The electron beam control tube has participated in the electron beam filtering technology, which can effectively filter out the low-energy electron beam that does not work for CT imaging. Reduce the radiation dose of rays; liquid bearing tube, liquid metal-based liquid bearing replaces steel ball-centered bearing, zero wear, zero vibration, and can provide high heat dissipation rate; add anode cooling technology to CT tube , the anode cooling rate and heat production rate are almost equal, and the tube can be cooled in time; the metal-ceramic CT tube increases the shell strength of the tube and improves the vacuum degree of the tube. The research and development has brought new blood and injected new impetus.

With the implementation of the hierarchical diagnosis and treatment system in my country, the demand for CT in the primary medical market has increased, and the demand for CT tubes has also increased; andCT tubeIt needs to be changed regularly according to the application status, the price is high, it belongs to high-value consumables, and the market is broad. At present, the domestic market relies on imports, and the level of localization needs to be improved urgently. CT tubes have great potential.