Classification and development of lighting fixtures!

2021-04-23 08:44:15 lighting 1

The development history of electric lighting is rich and colorful, which is composed of various types of electric lamps, which will be introduced one by one in the following.

1. Incandescent lamp

In 1909, American scientist Corridge invented tungsten filaments as filaments, which improved the brightness and lifespan of incandescent lamps. The filament in the glass bulb is heated by energization, which causes the filament to generate thermal radiation and emit light. The lamp holder is the electrical and mechanical connection part of the incandescent lamp. According to the form and purpose, it can be divided into screw type lamp holders, focusing lamp holders and special types. Lamp holder. Commonly used in residential basic lighting and decorative lighting, it has the advantages of easy installation, immediate start-up, and low cost. It has a wide operating voltage range, from a few volts provided by the battery to the mains voltage, and is inexpensive and does not require additional circuits. Its main application is home lighting and places where dense low-voltage lamps are needed, such as flashlights, console lighting, etc. Only 10% of the input energy is converted into visible light energy, and the typical life span ranges from tens of hours to thousands of hours.

Incandescent lamp, also known as electric bulb, is a kind of lamp that uses electric resistance to heat a thin wire (usually tungsten wire in modern times) to incandescence to emit light. The periphery of the incandescent lamp is made of glass, which keeps the filament under vacuum or low-pressure inert gas to prevent the filament from oxidizing under high temperature. Incandescent lamps with different uses and requirements have different structures and components. Although the light efficiency of incandescent lamps is low, the light color and light collection performance are very good. It is a large output and widely used electric light source.

2. Tungsten halogen lamp

In 1959, the invention of the halogen tungsten lamp brought the technology of incandescent lamp to a new level and increased the life of the incandescent lamp. Compared with the halogen-free incandescent lamp with the same rated power, the volume of the tungsten halogen lamp was much smaller and allowed to be charged. Into the heavier gas (more expensive) at high pressure, these changes can extend the life or improve the light efficiency. Similarly, the halogen tungsten lamp can also be directly connected to the power supply to work without a control circuit. The service life of an ordinary incandescent lamp is 1000 hours, and the halogen tungsten lamp is half longer than it, and the luminous efficiency is increased by 30%. Tungsten halogen lamps are widely used in motor vehicle lighting, projection systems, special spotlights, low-cost floodlights, stage and studio lighting, and other occasions that require compactness, convenience, and good performance to exceed non-halogen incandescent lamps.

3. Fluorescent light

Fluorescent lamps appeared in the 1940s, which used the principle of gas discharge to generate light energy. Since the emitted light is mainly ultraviolet and less infrared radiation, the luminous efficiency is higher than that of incandescent lamps. This kind of lamp replaces incandescent lamps, which will save energy by 75% and increase the life span by 8 to 10 times. Our commonly used fluorescent lamps mainly include fluorescent lamps, high-lumen single-ended fluorescent lamps, and energy-saving lamps (compact fluorescent lamps), which have been widely used in commercial and industrial lighting. It is commonly used in general public buildings such as offices, shopping malls, and residential buildings. It has many optional light colors and can achieve high illuminance while taking into account the advantages of economy. It will also emit a lot of beautiful and colored light. This is determined by the nature of the chemicals contained in the phosphor. For example, the one coated with magnesium tungstate will emit blue-white light, and the one coated with cadmium borate will emit reddish light. Through the innovation of design, the development of phosphors, and the application of electronic control circuits, the performance of fluorescent lamps has been continuously improved.

4. Low pressure sodium lamp

The appearance of the steam lamp is that the steam of various elements sealed in a glass tube is energized to emit light. Steam lamps include mercury vapor lamps and sodium vapor lamps. The light efficiency is high, but it only radiates monochromatic yellow light. It is impossible to distinguish various colors under this kind of lamp lighting. The main applications are: road lighting, security lighting and outdoor applications in similar occasions. Its light efficiency is twice that of fluorescent lamps and 10 times that of tungsten halogen lamps. Compared with fluorescent lamps, the discharge tube of the low-pressure sodium lamp is a long tube, usually bent into a "U" shape. The discharge tube is placed in an evacuated sandwich outer glass bulb, and the sandwich outer glass bulb is coated with an infrared reflective layer to To achieve the purpose of saving energy and improving greater light efficiency.

5. High intensity discharge lamp (HID)

These lamps are all high-pressure discharge lamps, which are characterized by a short, high-brightness arc-shaped discharge tube. Usually there is a certain shape of glass or quartz shell outside the discharge tube. The shell is transparent or frosted, or coated with a layer of fluorescent light. Pink to increase red radiation. Divided into high pressure mercury lamp (HPMV), high pressure sodium lamp (HPS), metal halide lamp (M-H)

6. Induction light

The electrodeless gas discharge lamp that just appeared soon. The required energy is coupled into the discharge through the high-frequency field, and the secondary winding of the transformer can produce an effective discharge. In terms of form, the induction lamp is another form of compact fluorescent lamp, but the high-voltage part may be different. This kind of lamp is not limited to a long tube shape (such as a fluorescent tube), and can emit light instantaneously. The operating frequency is within a few megahertz and requires special electronic circuit devices to drive and control the ignition of the lamp.

7. Electroluminescence lighting

Including many types of light-emitting panels and light-emitting diodes, LED is a new photoelectric lighting technology with a wide range of applications, combining multiple advantages of the above photoelectric technology.