4-Inch Air-Cooled LEDs

(Product ID: LM4X-DM-XXX, LM4X-DMHP-XXX )

Where water-cooling is not an option, the choice is 4-inch, air-cooled LEDs. The 4-inch, air-cooled LEDs are utilized in larger wind tunnels or test facilities where a model is relatively far (more than 2 feet). They offer nearly the same power output as the water-cooled LEDs without the need for an external water source. The LED is composed of an LED head with drive electronics and power supply built into the housing. There are two options available:

1.) The continuous 4-inch, air-cooled LED light source provides uniform, stable illumination, for radiometric pressure and temperature sensitive paint measurements. The unit operates continuously or in long-pulse mode, designed for radiometric systems using the continuous/long-pulse driver (module for radiometric). The operation mode is set using an external toggle switch. In long-pulsed mode, the pulse width and frequency are set by sending an external TTL signal to the BNC trigger input. The duty cycle may be set from 0% to 100%.

2.) The lifetime 4-inch, air-cooled LED light source provides uniform, stable illumination for lifetime pressure and temperature sensitive paint measurements. The system is over-driven and designed for lifetime acquisition systems using the short-pulse/high-power driver (module for lifetime). Over-driving the unit gives a higher peak power per pulse than the continuous LED system. Because it is over-driven, the duty-cycle is limited to 5%. Operation is controlled by applying a TTL signal to the external BNC. The maximum pulse width is limited to 1-ms. The LED has a built-in safety circuit to protect the LED head if the duty-cycle limits are exceeded.

The light distribution from either system is approximately Gaussian for distance greater than 18-inches (45-cm) from the source. The units are available in 400-nm and 460-nm packages, however, other wavelengths are available upon request. No external cooling source is required. The unit is cooled by two fans built into the package which drive air to the heat sink.

Ordering Information:

Continuous LED System: LM4X-DM-XXX (LED head with DC/long pulse driver)
Lifetime LED System: LM4X-DMHP-XXX (LED head with short-pulse/high-power driver)

**Note: "-XXX" denotes wavelength for LED heads.