The difference between LED lighting and OLED lighting
LED and OLED as a new semiconductor lighting technology, known as the fourth generation light source or green light, compared to traditional lighting products, it has energy-saving, environmental protection, long life, small size and other characteristics, it can be widely applied in various directions , display, decoration, backlight, general lighting and urban areas such as night.
Thus, in recent years some of the world's developed countries are actively developing OLED and LED semiconductor lighting. However, LED and OLED due to the different works and production process, there is their own characteristics.
LED stands for light-emitting diode, the general use of Group III-IV semiconductor materials and inorganic chemical vapor deposition (CVD) process. As with conventional semiconductor industries, the higher cost of the process, it is difficult to achieve large size
Therefore, LED can only be applied in the form of a point light source. Indoor general lighting, illumination in order to achieve a certain space, LED requires high brightness, so in order to prevent glare, resulting in soft light, LED lampshade is often necessary to use the installation. But this way, the luminous efficiency of LED lamps will drop.
If you want to make use of LED surface light source, such as an LCD backlight, you need a combination of a plurality of LED and light guide plate with complex optical systems. In addition, LED luminous efficiency as the temperature rises and abrupt decline.
Because LED volume is very small, the heat generated during the operation difficult distribute out, it must be equipped with a heat sink for the LED lamps. Based on the above several reasons, the advantages of LED light source technology, such as emission efficiency, lightweight and cost advantages in the production of a lamp post will be greatly discounted.
White LED current is generally used covering the phosphor powder blue LED on the way to achieve (as shown). Phosphor powder excited by blue light emitted by the LED will produce a yellow light, and then mixed together with white light blue LED itself. Although this method is low cost, but there are many shortcomings.
On the one hand, the white light generated in this way CRI will not ideal, that is, objects such white color under irradiation awry, making it unsuitable for use in high color quality requirements occasions; on the other hand, the phosphor powder aging faster than a lot of the blue LED, white light emitted will lead to a drift of blue, and thus shorten the life span.
OLED stands for organic light emitting device, by definition, OLED is an organic semiconductor material-based devices. Materials used are small molecule OLED and polymer of the points, the current industry of mainly small molecule organic materials based.
Due to the small molecule OLED lower cost glass as the substrate, and a large area vacuum thermal evaporation deposition process, so that a surface light source OLED technology is innate. OLED process technology process technology without LED ultra-high vacuum and high temperature environments, cost competitiveness is much higher.
Theoretically organic materials than inorganic semiconductor material is much lower, but is currently limited to industrial scale production and material utilization and other factors, the cost of organic material remains high. However, with the expansion of industrial scale, the cost of organic material will be substantially reduced.
OLED generally luminous uniform soft close Lang Park (lambert) radiation distribution, so OLED itself is almost a lamp without shade with use. At present, mainly in the hair red, green and white OLED (yellow) and blue three primary colors sequentially laminating organic material mixed.
In addition, the characteristics of the emission spectrum of the organic material is a half-peak width is very wide, so the white OLED spectrum no major gaps, which makes the color rendering index of OLED light source is very good, especially suitable for indoor general lighting, and even professional photography applications. Further, by adjusting the proportion of each color light emitting material may produce light of any color to suit different applications.
Since the OLED has a very large light-emitting area, the heat generated when the work can be promptly dissipated without heat sink. Therefore, OLED can be very thin, space-saving costs. In addition, OLED can be designed into a variety of shapes, greatly expand the OLED lighting applications in the field of space in the Art Deco.
OLED killer feature can be transparent, even to achieve the traditional lamp completely unimaginable application methods, such as the OLED fabricated on glass windows during the day to let natural light shine through, as the use of lighting at night.