PlasmaDetekProducts015

Plasma Cell

The cell of the PED is generally made of quartz. The material used has strong UV transmission properties. It is also durable, inert and

heat resistant.

LDetek plasma detector has a specific cell design that provides a stable plasma. This unique conception will help getting low noise

and good sensitivity when nitrogen is flowing in the detector along with the argon or helium. The wall cell design made of quartz

combined with specific electrodes shape and inlet/outlet flow path configuration are some of the key parameters that give the

performance of a PED.

Plasma Generator

The plasma generator is also quite important. Its specific voltage, frequency and current make the glow discharge in the cell very stable.

The combination of the cell design and generator is critical in such application. LDetek has developed a perfect combination to get a

stable light emission from the plasma. The components of the generator are well proven to be efficient and resistant over the years.

The generator is also based on a duty cycle controlled system that extends lifetime of the cell. The cell is put ON and OFF on a specific

frequency and period to help the system to give the performance desired as well as decreasing the degradation of the detector.

Detection principle

Plasma Emission Detector (PED)

Analyzer Components

The LD8000 is using a Plasma Emission Detector where the principle is based on a spectroscopic emission cell. This is actually

not a new technique, but the unique design of LDetek in terms of frequency, intensity as well as the mechanical and electrodes

conception make the system very stable and efficient.

A luminous phenomenon, called electroluminescence, is created and is used as emission technique to quantify the nitrogen

analyte. A plasma is created with the argon or helium flowing in the cell and when concentration of nitrogen changes, spectral

lines emission change as well. The light is then directed in an optical filter that will discriminate the spectral lines. At the end, a

photo-diode will convert light to current to make a proportional electric signal of nitrogen in the sample.

With its unique design, LDetek achieves unsurpassed performance that provides now a reference trace nitrogen in argon or

helium analyzer.

Figure 1

Plasma detector principle

Figure 2

Light to current transformation