LED History:
1907: Henry Joseph Round laid the foundations of LED technology by discovering electroluminescence. However, LEDs during this period were quite different from today’s commercial LEDs.
1961: Robert Biard and Gary Pittman invented the first infrared LEDs. This marked one of the first practical applications of LED technology and is now used in many areas such as remote control systems.
1962: Nick Holonyak Jr. produced the first red LED, laying the groundwork for modern LED technology. This marked the beginning of LEDs’ ability to produce colored light.
Mid-1970s: Commercially viable LEDs for practical use began to be developed. However, LEDs during this early period were not as bright or efficient as they are today.
1990s: The development of blue and green LEDs enabled the creation of full-color LED displays and lighting.
Early 2000s: The development and commercialization of white LEDs made LED lighting more widespread in residential and commercial applications.
During this process, LED technology revolutionized both lighting and optical lens technologies. The rise of LEDs, especially, led to new possibilities and requirements in the design of lighting optical lenses. With continuously evolving LED technology, the design of optical lenses has also been continuously improved to be more effective in directing light accurately and focusing it on desired areas.
Commonly Used LEDs::
Lighting LEDs can have different characteristics to meet various lighting needs. The use of appropriate optical lenses for these LED types ensures that light is directed correctly. Here are common LED types and the optical lenses used:
Spot LEDs: Designed to provide a focused beam of light. They are commonly used in lighting fixtures or decorative lighting applications and are often paired with narrow-angle optical lenses.
Flood LEDs: Designed to illuminate a wide area. They are preferred for outdoor lighting, stage lighting, and industrial lighting, and are often paired with wider-angle optical lenses.
Street LEDs: Designed to light up large areas such as roads, streets, and highways. They come with specially designed narrow and long-beam optical lenses to provide light over longer distances.
Decorative LEDs: Used for aesthetic lighting purposes. They are preferred for lamp strips, decorative fixtures, and lighting effects and are often available in various colors, paired with special optical lenses for color-changing effects.
Panel LEDs: Designed to provide general lighting on surfaces. They are commonly used in indoor lighting applications such as offices, stores, and schools and typically come with flat optical lenses that provide homogeneous light distribution.
Reflector LEDs: Used in spot and flood lighting applications, especially when paired with reflectors. Reflector LEDs ensure more efficient reflection of light and the creation of the desired beam. LED Terminology:
Various Terms are Used to Describe LEDs Used in Lighting:
SMD LED (Surface Mounted Device LED): LEDs mounted on the surface. These LEDs do not require soldering during assembly and are commonly used in flexible printed circuit (FPC) strips or LED panel lighting fixtures.
COB LED (Chip-on-Board LED): Many LED chips are directly mounted on a substrate. COB LEDs provide higher light intensity and more homogeneous light output, especially used in spotlights and projectors. High Power LED: LEDs with high power, usually operating at 1 watt or higher. They provide high light output and are commonly used in lighting fixtures and street lighting.
Mid Power LED: LEDs with medium power, typically operating between 0.1 to 1 watt. Due to lower power consumption and smaller size, they are preferred for panel lighting and decorative lighting applications.
RGB LED: Consists of a combination of red, green, and blue (RGB) LEDs. They can produce light of different brightness and intensity levels of all three primary colors, ideal for colorful lighting effects. Tunable White LED: LEDs that can change color temperature. They can be adjusted over a wide range of color temperatures from cool white to warm white and are used to adjust color temperature in lighting fixtures.
CRI (Color Rendering Index) LED: A measure of the ability to accurately render colors. LEDs with high CRI values produce light closer to real colors and natural light. Directional LED: LEDs that direct the light beam in a specific direction. They are used in applications such as spotlights and projectors.
These terms are used to describe different characteristics and application areas of LEDs, aiding in the selection of the right LED for specific applications.
History of Lighting Optical Lenses:
The history of optical lenses for lighting is not as old as lighting technologies themselves, but it has played a significant role in the field of lighting.
Early 1800s: The use of lenses for lighting increased with the development of gas lamps and subsequently with the widespread use of electric lamps. During this period, lenses began to be used to provide focused and more efficient light.
Early 20th Century: The proliferation of glass lenses was a significant development, especially in industrial lighting. They were used for more effective light distribution in industrial facilities, street lighting, and other large areas. Mid-20th Century: The development of plastic lenses was a turning point in lighting optics. Plastic lenses were lighter and cheaper, making them more widespread. 1970s and 1980s: With the emergence of new lighting technologies such as high-pressure sodium lamps and metal halide lamps, the design and use of optical lenses also evolved. These lamps, producing more efficient and powerful light, required more complex optical systems. 2000s and Beyond: The rise of LED technology has had a major impact on lighting optics. LEDs inherently provide directional light, opening up new possibilities in the design of optical lenses. With the widespread use of LEDs, especially in applications such as street lighting and building lighting, the use of specially designed optical lenses has increased. Today, lighting optical lenses play a critical role in directing light accurately and focusing it on desired areas. With continuously evolving LED technology, the design and efficiency of lenses are also continuously being improved.
Plastic Optical LED Lenses:
These are optical accessories used in LED lighting systems to direct and distribute light properly. These lenses are typically made from high-quality plastic materials such as polycarbonate or acrylic and can have various shapes, sizes, and properties.
Advantages of plastic optical LED lenses include:
Flexibility and Design Variety: Plastic lenses can be easily produced in complex shapes and different sizes, offering various design options to meet different lighting requirements. Cost-Effectiveness: The production of plastic materials is generally cheaper, reducing the cost of plastic lenses. This can result in cost savings for large-scale lighting projects. Lightweight: Plastic lenses are lighter than glass lenses, making assembly and installation processes easier. Impact Resistance: Plastic materials such as polycarbonate and acrylic are resistant to impacts, increasing the durability of lenses and preventing breakage. High Efficiency: Plastic lenses can distribute and focus LED light more efficiently, resulting in more homogeneous light output.
Plastic optical LED lenses are widely used in indoor and outdoor lighting applications, street lighting, automotive lighting, industrial lighting systems, and many other areas. Optical lenses are essential components to make the most of the advantages offered by LEDs, as directing light in the desired direction increases efficiency and helps achieve desired lighting effects.
In this article, we discussed the history of LED technology and LED lenses and some LED terminology.
