Light Emitting Plasma
How it Works

LEP is a revolutionary electrodeless lamp which is energized by Radio frequency (RF) Power. The clean, bright, high CRI, white light generated by a tiny tic-tac capsule sized bulb is very similar to daylight..

Emitter : A solid-state RF generator and micro-controller
Radio Frequency (RF) Driver : Radio Frequency (RF) Driver:

A radio-frequency signal is generated and amplified by the RF driver, which is guided into the ceramic resonator through a low loss coaxial cable. The structure of the resonator concentrates the RF field, delivering energy to the fully-sealed quartz lamp without electrodes or filaments. The highly concentrated electric field ionizes the gasses and vaporizes the halides in the lamp Ė creating a plasma state at its center Ė resulting in an intense source of white light. Inside the back of the lamp, a diffuse yet highly reflective material is used to reflect all of this light to the forward direction in a Lambertian pattern. The color of the light is tailored by the fill chemistry inside the lamp to provide a naturally white and high color rendering light.
The brilliance of LEPís architecture lies in its simplicity. By energizing a plasma arc without using filaments or electrodes, all failure modes and inefficiencies of traditional HID technology are eliminated, leaving behind an incredibly bright and stable source.

Step 1 - An RF circuit is established by connecting an RF power amplifier to a ceramic resonator known as the ďpuckĒ. In the center of the puck is a sealed quartz lamp that contains metal halide materials and other gases.

Step 2 - The puck, driven by the power amplifier, creates a standing wave confined within its walls. The electric field is strongest at the center of the lamp, which causes ionization of the gases, creating a glow.

Step 3 - The ionized gas in turn heats up and evaporates the metal halide materials forming an intense plasma column within the lamp. This plasma column is centered within the quartz envelope and radiates light very efficiently.

Increase light output without compromise

One of the key benefits of LEP over LED and HID is the ability to scale in lumen output without losing efficiency and increasing system overhead like size and cost. For example, in order to double the light output of an LED fixture, you need twice as many LEDs, optics, and driver. This proves to be problematic: thermal cross-talk lowers efficiency of the individual LEDs, adding components drive up cost and compromises system reliability, and luminaire size increases proportionally. LEP sources, on the other hand, can double in light output by simply scaling the size of the bulb and using a higher power amplifier which only marginally impacts system performance. In addition, the source size remains small compared to the illumination optics and the emitter becomes more efficacious, giving you higher optical efficiency at high outputs.
LEPís maximum benefits are realized at high lumen output
When plasma light production is scaled to higher lumen packages, its efficiency and cost of ownership benefits increase compared to other lighting technologies.


Increase light output without compromise

The LEP emitter is constructed of a small electrode-less lamp encased by a ceramic resonator. This unique design produces light from a very compact area in a forward direction into a lambertian pattern. The quartz lamp acts as a point source due to its minimal size, providing many advantages in a luminaireís optical performance. Smaller sources inherently reduce the amount of optics needed to achieve the required level of glare cutoff and illumination, while ensuring excellent uniformity.

Because LEPís directionality causes all of its light to be directed toward the area needing illumination, there are no optical losses from light going in the wrong direction. In most applications, LEP luminaires can achieve greater than 90% optical efficiency into the desired light distribution.
Natural illumination for enhanced visibility


Energy savings using LEP luminaires comes from a combination of source and application efficiencies

  • LEPís source efficacy, lumens created per watt consumed, is 15-20% higher than an HID source, because no power is wasted in heating electrodes. Plasma light source efficacy ranges from 115 to 150 LPW at operating temperatures.

  • LEP sources can be utilized to achieve application efficiency more effectively than HID, induction lighting or LED because of its directionality and size. The directional source prevents light from being trapped inside a luminaire. Point source optics effectively maps the source to the illuminated area, preventing unwanted light spill (a source for glare and light-pollution).

LEP is the only high-intensity light source that can be dimmed almost instantly to 20% of light output by dimmers or daylight sensors.

Dimming (based on occupancy or demand response) further reduces energy costs, and actually lengthens the life of the plasma lamp beyond the rated lifetime.


Eliminate failure modes and lumen degradation found in traditional lighting technologies

  • Even with extensive operation over long periods of time, LEPís electrode-less quartz lamps do not display electrode failures or wall darkening that affects traditional metal halide and HPS lamps.

  • The unique construction of LEPís solid-state RF generator produces a rugged device made to withstand extended, continuous use.

  • Unlike LED luminaries which require several devices to generate sufficient light, LEP uses a single source, thereby reducing failure points and increasing overall system reliability.

LEP System Lumen Maintenance

An LEP system for general lighting applications is rated for 70% lumen maintenance (L70) after 50,000 hours of use. Unlike typical HID light sources, LEP sources do not need to be de-rated for the length of operating cycles. In comparison, a typical 400W Metal Halide lamp yields a 50% survival rate after only 3,000 to 5,000 hours of use. Its lifetime is de-rated by as much as 25% for lamp orientation, and up to 50% for short operating cycles.

LEP is the only high-intensity light source that can be dimmed rapidly to 20% of light output by dimmers or daylight sensors. Dimmed light output reduces energy costs and actually lengthens the life of the plasma lamp beyond the rated 50,000 hours.

The extended life of Light Emitting Plasma compared to other technologies results in dramatically lower maintenance costs.
Seamless Controls Integration
Save energy and adjust lighting for the environment by integrating LEP with lighting control systems

The controllable solid-state driver and a responsive emitter configuration make LEP the only high-intensity source that can be dimmed down to 20% of light output, in just a matter of seconds, with both analog and digital controls. In addition to offering fine control over light output, dimming actually increases the longevity of the LEP source and the drive electronics. This capability creates an enormous opportunity for reducing energy consumption and operating costs when combined with the use of dimmers and occupancy or daylight sensors.

The LEP driver offers built-in functionality including:

  • Direct 1-10V input for dimming

  • Direct low voltage input control by occupancy sensors

  • Serial interface for digital controls (can interface to DALI and other controls protocols)

  • Logging of operating parameters including temperature, voltage, current and other diagnostics