This section provides an overview for proportional counters as well as their applications and principles. Also, please take a look at the list of 3 proportional counter manufacturers and their company rankings. Here are the top-ranked proportional counter companies as of September, 2023: 1.Global Nucleonics., 2.PHOTONIS, 3.Canon Electron Tubes & Devices Co., Ltd..
A proportional counter is a type of radiation detector. It detects radiation by measuring the number of electrons (electric current) produced by the ionization of gas molecules when energetic particles pass through a gas.
Ionization chambers and GM (Geiger-Müller) counters are radiation detectors based on similar principles, but they differ in the magnitude of the voltage applied to measure the current. Ionization chambers operate at lower voltages than proportional counters, while GM counters operate at higher voltages than proportional counters.
Proportional counters detect radiation such as X-rays, α-rays, β-rays, γ-rays, and neutrons and measure radiation counts and energy. Because of their simple structure and relatively easy manufacturing, proportional counters are often used as detectors in academic research and other fields.
Generally, they are used to measure radiation dose in the air, especially for neutron detection and β-ray contamination detection. Proportional counters for X-rays are also sometimes incorporated as detectors in X-ray fluorescence film thickness meters, which are used for non-contact measurement of plating thickness, etc., because of their larger incident window and higher efficiency compared to semiconductor detectors.
The proportional counter is usually a cylindrical aluminum vessel filled with a mixture of inert gases such as argon, helium, or neon, and methane or butane and operated by applying high voltage to wires stretched inside the tube. The cylindrical vessel has an incident window through which radiation enters the tube.
When the incident radiation passes through the gas, the gas along its path is ionized to produce electrons and cations. The electrons produced are called primary electrons. The primary electrons are accelerated by the electric field in the tube and ionize the gas anew, and these ionized electrons cause further ionization, resulting in a phenomenon called gas amplification in which the number of electrons increases explosively. The amplified electrons flow into the wire inside the tube and are detected as an electrical pulse.
Since the number of amplified electrons is proportional to the energy of the incident radiation, this detector is called a proportional counter. The amplification rate of electrons depends on the type of gas and the applied voltage, but if the gas and voltage are known, the energy of the incident radiation can be measured.
An ionization chamber operates on a similar principle to the proportional counter but operates at a lower voltage and therefore does not amplify the gas. Therefore, proportional counters have the advantage of higher sensitivity than ionization chambers. On the other hand, proportional counters have the disadvantage that they cannot measure the number of primary electrons as accurately as an ionization chamber, and their energy resolution is inferior.
*Including some distributors, etc.
Sort by Features
Sort by Area
Founded in 1915, Canon Electron Tubes & Devices Co., Ltd. is a Japanese manufacturer operating under Canon, Inc. The company's headquarters is located in Otawara, Tochigi, with representative offices in Tokyo, China, the USA, and Europe. The company introduced Japan's first X-ray tube in 1915. Since then, it has developed various components incorporating X-ray tubes for medical, industrial, and scientific applications. Additionally, the company produces environmentally conscious products (ECPs) to minimize environmental impact. For example, the multi-beam klystron can be operated with a low operating voltage for a relatively longer period of time due to the optimized cathode loading.
PHOTONIS, a well-reputed French company founded in 1937, specializes in manufacturing electro-optic components and detectors. They offer a wide range of products, including photomultiplier tubes, image intensifiers, and microchannel plates. PHOTONIS serves various industries, such as scientific research, defence, medical, and industrial applications. Their products are used in applications like night view, mass spectral analysis, and space exploration. PHOTONIS is present internationally with offices and distributors in different countries. Devoted to excellence and environmental responsibility with various certifications, ensuring reliability and safety for customers.