Why LEDs
Why LEDs?
Why LEDs instead of Bulbs?
Why CoolLED LEDs?
LEDs (Light Emitting Diodes) are semiconductor devices which emit photons around a specific peak wavelength when an electrical current is passed through them. As semiconductors, they offer:-
- Instant on/off
- Fast switching
- Reliability
- Stability
- Long lifetime
- Low energy use
- Easy intensity control
- Simple to automate
High light intensities are achievable. Although LEDs are more than three times as efficient as conventional incandescent bulbs, they are only 20 – 30% efficient. High brightness results in high heat flux densities so it is essential to provide the appropriate cooling to ensure that the LEDs do not overheat resulting in spectral drift and premature failure.
The conventional light source is a high pressure Mercury or Metal Halide bulb which creates multiple peaks across a broad spectrum of energy. The majority of this energy is unnecessary or needs to be removed by filtering depending on the application. LEDs do not present such problems.
There are significant Health & Safety benefits in selecting LEDs instead of high pressure lamps. LED products do not contain Mercury which is considered to be a hazardous material. Metal Halide lamps are Mercury based. Mercury lamps emit UV radiation which can damage eyes. It can also damage many types of sample be illuminated by the lamp through photo-bleaching. Due to the high temperatures and pressure, Mercury lamps can explode. Although rare, this is a serious consideration for any laboratory using high intensity lighting.
There are no special disposal requirements for LEDs.
The benefits of LEDs can be considered from three aspects
Operational Experimental Environmental
Instant on/off Fast switching- no shutters No mercury
No warm up time Simple intensity control
No cool down time Simple systems integration No risk of exploding bulbs
No bulb replacement Stable output for many years
No bulb alignment Reduced photobleaching Low energy usage
Only CoolLED is using active-cooling of LEDs in their excitation products. As discussed above, LEDs are more efficient than conventional light sources but still produce much heat. With CoolLED LED products, this heat is removed by active-cooling so that the LEDs are held within a constant temperature range. By controlling the temperature, CoolLED can drive the LEDs more powerfully. This results in greater intensities. In addition, by active-cooling, the stability, reliability, and lifetime of the LEDs is greater.
It is CoolLED's expertise in LED assembly and the use of active-cooling which means that it can offer intensities up to 5x greater than other LED excitation products using commercially available packaged LED parts.
CoolLED guarantees its LAMs (LED Array Modules) for 3 years which keeps running costs low. In fact, LAMs are expected to last indefinitely. This makes CoolLED LED products cost-effective as well as offering superior illumination performance.
