According to LEDinside’s Assistant Research Manager Joanne Wu, surveillance systems have become ubiquitous and governments in developed countries have set aside bigger budgets for upgrading their security-related infrastructures. Demands have become even stronger in areas with political turmoil and social problems, such as Central and South America, the Middle East, and the Indian subcontinent.

As a result, major IR LED manufacturers have greatly profited by supplying components to surveillance products. These companies include EPITEX from Japan and Osram Opto from Germany. Taiwan-based companies that also benefited from the growth of the IR LED market are Epistar, Epileds, and High Power Lighting.

With its main wavelength range of 750nm~1400nm, near-infrared (NIR) LED is primarily used for imaging as in the case of surveillance cameras. Cameras with night vision ability are typically equipped with digital image sensors based on one of these two technologies: charge-coupled device (CCD) or complementary metal oxide semiconductor (CMOS).

These sensors furthermore come with IR LEDs of 850nm or 940nm wavelength. Due to its high cost, CCD has difficulty making inroads in the security application market. Standard surveillance cameras therefore use CMOS sensors paired with 850nm IR LEDs in order to get the best price-performance ratio.

However, some high-end surveillance cameras carry the more costly 940nm IR LEDs since they are less likely to create a visible red dot than the 850nm. Note that this red dot effect that sometimes occur with IR LEDs do not mean the LEDs are of poor quality. On the whole, both vendors and consumers choose between 850nm and 940nm IR LED products based on their respective needs.

In her survey of the IR LED’s development, Wu believes the 3535 package will eventually replace the traditional LAMP type package. Presently, the packaging of IR LEDs is divided into three types – LAMP, SMD, and high-power LED package. Adopting high-power LEDs will reduce the number of LEDs as well as simplifying circuit and heat dissipation design, thus creating convenience for the system manufacturers.