November 25th, 2009 at 10:09 am
Posted by Copywriting in Copywriting Blog
Sodium Vapour Lamp consists of a discharge tube made from a heat resistant glass, containing a small amount of metallic sodium, neon gas and two electrodes, Neon gas is added to start the discharge and to develop enough heat to vaporize the sodium. Because of law pressure inside the tube, a sufficiently long tube required to obtain more light. To reduce the overall dimension of the lamp, this tube is generally bent into U-shape.
The light produced by this lamp is yellowish which is produced at its optimum pressure of about 0.004mm of mercury. This pressure is obtained at a temperature of about 280
