We see plasma TVs everywhere these days, but it’s often wondered exactly how a plasma TV works. It actually wasn’t until a handful of years ago that the plasma TV began to really make its debut with the public. How do these devices work however? How is it that they are so thin and produce a similar (or sometimes even better) picture than the original cathode ray tube technology?
- Essentially, the plasma TV works by illuminating very small fluorescent lights to comprise a picture. There are three of these fluorescent lights contained in a pixel, and they are red, green and blue. The plasma will manipulate the intensity of each of these tiny lights to produce the entire color spectrum and ultimately create an image on screen.
- Inside of each tiny light, is a gas called plasma. The plasma is basically made up of electrons and ions that are electrically and negatively charged (respectively). Under normal circumstances, a gas is typically comprised of uncharged particles. By freeing electrons into the gas and setting up an electric voltage across it, this causes a sudden change of events. The electrons that are free will crash into the atoms, and this will ultimately knock other electrons loose. Now that the atom is missing an electron or two, it begins to lose its stability. The atom now has a negative charge which officially makes it an ion. While the electric voltage is surging through the plasma, the particles that are negatively charged are dashing for the positively charged area, and vice versa.
- While all of the rushing around is going on, particles are continually crashing into each other. These impacts are causing the gas atoms in the plasma to excite, and ultimately they release “photons.”
- The plasma TV uses “xenon” and “neon” atoms. These release “light photons” when they get excited. Most of the time, these atoms are releasing ultraviolet photons. These are not the photons that we see with our eyes, but these photons actually excite the perceptible light photons.
- Inside of the plasma TV, the xenon and neon atoms are contained in thousands and thousands of cells in between two glass plates. Also positioned between the two plates of glass are long electrodes. There are two types of electrodes that are contained here and they are the address electrodes and the transparent display electrodes. The address electrodes are positioned vertically in the back, behind the cells. The transparent display electrodes are located horizontally behind the front plate of glass. Both groups of electrodes are equal in size to the entire screen.
- In the process of ionizing gas in a specific cell, the plasma TV has a computer that charges the electrodes that meet at that particular cell. This happens thousands of times a second. When these meeting electrodes are charged, an electric current will begin to flow throughout a gas’s cell. This electric current creates a very swift stream full of charged particles, which in turn causes the gas to release the ultraviolet photons.
- These ultraviolet photons that are released then intermingle with the phosphor that is coated on the inner cell wall. These phosphors will emit light because they are being exposed to the ultraviolet light. These phosphors will ultimately release lights of different colors. Each and every pixel consist of three other inner pixel cells, and each other have different color phosphors (red, green and blue). The plasma TV works by varying the intensities of the electric currents, and they can comprise to create any color in the spectrum!