Ultraviolet lamp UV: principles of operation and application
05 May, 2024
By hqt
In this article, we will look at how an ultraviolet UV lamp works, their different types, and the variety of applications in everyday life, industry, and medicine.
How does a UV lamp work?
An ultraviolet (UV) lamp works by converting electrical energy into ultraviolet radiation. It works by using an electric current to excite gas or metal atoms inside the lamp, causing it to emit ultraviolet photons.
The process works as follows:
Electric Current : When the lamp is turned on, an electric current flows through the gas discharge or through the electrodes, which creates an electric field inside the lamp.
Excitation of atoms : An electric field excites the atoms of a gas or metal inside the lamp, causing them to become excited. As a result, the excited atoms enter a metastable state.
Emission of ultraviolet photons : When atoms return from a metastable state to the ground state, they emit ultraviolet photons. The wavelength of the ultraviolet radiation emitted depends on the properties of the gas or electrode material used.
Additional Processes : Some types of UV lamps may have additional processes such as phosphorescence, which converts ultraviolet radiation into visible light or other forms of radiation.
Ultraviolet lamps can be used in various fields such as water and air disinfection, photopolymerization, defect detection, individuality in printing and others.
Basic principles of operation and types of UV radiation
Ultraviolet (UV) radiation is electromagnetic radiation with a shorter wavelength than visible light but longer than X-rays. The working principles and types of UV radiation can vary depending on their wavelength and spectral range. Here are the basic working principles and types of UV radiation:
Wavelength : UV radiation is divided into three categories depending on their wavelength:
UVA (long-wave radiation) has a wavelength of 320 to 400 nm.
UV-B (medium wave radiation) has a wavelength of 280 to 320 nm.
UV-C (shortwave radiation) has a wavelength of 200 to 280 nm.
Operating principle : UV radiation can destroy microorganisms and viruses by penetrating their cells and destroying their DNA or RNA. This makes it an effective means of disinfecting water, air and surfaces.
Types of Lamps and Radiation Sources : UV radiation can be generated by a variety of sources, including low, medium and high pressure UV lamps, UV LEDs, ultraviolet lasers, etc. UV lamps are commonly used in water and air disinfection systems, while UV LEDs have found applications in medical devices, sterilizers, polymerization equipment, etc.
Application : UV radiation is widely used in disinfection, sterilization, drying, polymerization, defect detection, photochemical reactions, as well as in medical and scientific research.
Overall, UV light is a powerful tool with a wide range of applications, but requires careful handling due to its potentially hazardous properties.
Technical characteristics and components of the lamp
The specifications and components of UV lamps can vary depending on their specific type and intended use, but here are the general specifications and components that are commonly found:
Wavelength : UV lamps can have different wavelengths depending on their type and spectral range (UV-A, UV-B, UV-C).
Wattage : The power of a lamp is determined by electrical parameters such as voltage and current, and may vary depending on its intended use. Power is usually indicated in watts (W).
Operating voltage and current : These are the electrical operating parameters of the lamp, which are determined by its design and construction.
Harness (Electrodes) : The harnesses inside the lamp are the wires or plates that generate the electric arc and initiate the radiation process.
Gas mixture : Inside the glass bulb of the lamp is a gas mixture that is used to create an electric arc and emit UV light. This mixture may include rare inert gases such as argon or krypton, as well as a small amount of mercury (for some types of lamps).
Glass Bulb : The glass bulb is the shell that contains the gas mixture and protects the internal components of the lamp. It also filters visible light, allowing only UV radiation to pass through.
Reflector : Some lamps may have a built-in reflector that increases the directionality and intensity of the light.
Ballast : Electronic or magnetic ballasts can be used to stabilize the electrical current and prevent the lamp from overheating.
These are the main components and characteristics that can be found in UV lamps. Specific technical parameters may vary depending on the specific model and manufacturer.
Types of UV ultraviolet lamps and their specifics
Ultraviolet lamps (UV lamps) vary in radiation type, wavelength, power, design and application. Here are some of the main types of UV lamps and their characteristics:
UV-A Lamps : These lamps emit ultraviolet radiation with wavelengths in the range of about 315-400 nm. They are used in a variety of applications such as polymerization, photolithography, materials inspection, and some types of medical diagnostics.
UV-B lamps : These lamps emit ultraviolet radiation with a wavelength of about 280-315 nm. They are often used to treat various skin diseases, sterilize air and water, and polymerize materials.
UV-C lamps : These are ultraviolet lamps with a wavelength of about 100-280 nm. They are commonly used for disinfection and sterilization of water, air, surfaces and medical equipment, as UV-C radiation has the highest bactericidal activity.
Germicidal UV Lamps : These lamps are specially designed to kill bacteria, viruses and other microorganisms. They usually use UV-C radiation and are widely used in medical facilities, public places and home use.
UV Water Disinfection Lamps : These lamps are specially designed to disinfect water by killing bacteria, viruses and other pathogens. They use UV-C radiation and can be installed in water purification systems for home or commercial use.
UV Air Disinfection Lamps : These lamps also use UV-C radiation to kill bacteria, viruses, and fungi in the air. They can be installed in ventilation, air conditioning, or stand-alone indoor air purification units.
These are just a few examples of the different types of UV lamps and their applications. Each type of lamp has its own unique specifications and purposes that can be selected based on the specific needs and requirements of the application.
Low pressure lamps
Low pressure lamps (LPL) are one of the types of ultraviolet lamp UV and have a number of features:
Operating principle : LND lamps work on the basis of fluorescent lighting. Electrons, passing through a gas mixture in the lamp, excite mercury or other inert gas molecules, which leads to the emission of ultraviolet light.
Spectral characteristics : LND lamps typically emit in the UVA and UVB range, with wavelengths of about 254 nm and 185 nm, respectively. This makes them effective for a variety of applications, such as sterilization, water and air disinfection, and polymerization.
Application : Low pressure lamps are widely used in medical institutions, food and beverage industries, water treatment plants, as well as home water and air purification devices.
Energy Efficiency : LND lamps feature low energy consumption and long life, making them a cost-effective choice for a variety of applications.
Safety : It is important to remember that ultraviolet radiation from LND lamps can be harmful to human health and requires careful handling. When using the lamps, it is necessary to follow the prescribed safety precautions and never look at their radiation directly.
Low pressure bulbs are an effective and widely used solution for various disinfection and lighting applications, but precautions must be taken when using them.
Medium and high pressure lamps
Medium and high pressure lamps (MPL and HPL) are also types of UV lamps, although their operating principles and applications are different from LP lamps. Here are some characteristics of these types of lamps:
Operating principle : Medium and high pressure illuminators operate on the basis of various mechanisms, including arc discharge lighting (ADL) and high frequency action on mercury and gas mixture (HF). They generate significant amounts of UV radiation in narrow spectral bands.
Spectral characteristics : Unlike LLP lamps, medium and high pressure lamps can have a wider spectrum of UV radiation, including UVA, UVB and UVC.
Application : These lamps are used in various industries such as water treatment, sterilization in medical facilities, industrial processes, polymerization and drying of coatings.
Efficiency : Medium and high pressure lamps are generally highly efficient in areas where intense UV radiation is required for disinfection or treatment.
Safety : As with LLD lamps, the use of MV and HID lamps requires precautions due to the potential health hazards of ultraviolet radiation.
Medium and high pressure lamps are powerful and efficient sources of UV radiation, and their selection depends on the specific requirements of the application. When using such lamps, their technical characteristics, safety and environmental requirements must be taken into account.
