What is a Flat Panel Monitor?

FPD = Flat Panel Display Flat panel display (FPD) has become the mainstream of future TV, but there is currently no strict definition internationally. Generally, this display is thinner and looks like a flat panel. There are many types of display. According to the display medium and working principle, there are liquid crystal display (LCD), plasma display (PDP), electroluminescence display (ELD), organic electroluminescence display (OLED), field emission display (FED), Projection display, etc.

Flat panel display

FPD = Flat Panel Display Flat panel display (FPD) has become the mainstream of future TV, but there is currently no strict definition internationally. Generally, this display is thinner and looks like a flat panel. There are many types of display. According to the display medium and working principle, there are liquid crystal display (LCD), plasma display (PDP),

Compared with the traditional CRT (cathode ray tube), the flat panel display has the advantages of thinness, lightness, small power consumption, low radiation, no flicker, and is beneficial to human health. At present, it has surpassed the CRT in terms of global sales. By 2010, it is estimated that the ratio of the sales value of the two will reach 5: 1. In the 21st century, flat panel displays will become mainstream products in displays. According to the famous Stanford Resources company forecast, the global flat panel display market will increase from 23 billion US dollars in 2001 to 58.7 billion US dollars in 2006, and the average annual growth rate in the next four years will reach 20%.

Flat panel displays are divided into active light-emitting displays and passive light-emitting displays. The former means that the display medium itself provides light

Flame Photometric Detector (FPD)

1.The principle of FPD

The principle of FPD is based on the sample burning in a hydrogen-rich flame, so that compounds containing sulfur and phosphorus are reduced by hydrogen after combustion, resulting in excited states S2 * (excited states of S2) and HPO * (excited states of HPO). When these two excited substances return to the ground state, they radiate about 400nm and 550nm spectra. The intensity of this spectrum is measured with a photomultiplier tube. The light intensity is proportional to the mass flow rate of the sample. FPD is a highly selective detector, which is widely used for the analysis of sulfur and phosphorus compounds.

2.FPD structure

FPD is a structure that combines FID and photometer, and began to be a single flame FPD. After 1978, in order to compensate for the shortcomings of single flame FPD, a dual flame FPD was developed. It has two separate air-to-hydrogen flames. The lower flame converts the sample molecules into combustion products, which contain relatively simple molecules, such as S2 and HPO; the upper flame produces light-emitting excited state fragments, such as S2 * and HPO *, there is a window aiming at the flame above. The intensity of chemiluminescence is measured with a photomultiplier tube. The window is made of hard glass and the flame nozzle is made of stainless steel.

3. Performance of FPD

FPD is a selective detector for the determination of sulfur and phosphorus compounds. Its flame is a hydrogen-rich flame. The air supply is only enough to react with 70% of the hydrogen combustion. Therefore, the flame temperature is low to generate excited sulfur and phosphorus. Compound debris. The flow rates of carrier gas, hydrogen, and air have a great effect on FPD, so the gas flow control must be stable. The flame temperature for sulfur-containing compounds should be around 390 , which can generate excited S2 *. The ratio of hydrogen and oxygen for phosphorus-containing compounds should be between 2 and 5, and the hydrogen-to-oxygen ratio should be changed according to different samples. The amount of carrier gas and make-up gas should also be adjusted appropriately in order to obtain a good signal-to-noise ratio.