21. At the end of life, many types of high-intensity discharge lamps exhibit a phenomenon known as " cycling ". 22. A gas-discharge lamp is an example of a device which, under certain conditions, has " negative differential " resistance. 23. A gas-discharge lamp is capable of exceeding the spectral power of direct sunlight in the infrared, especially when pulsed. 24. A "'mercury-vapor lamp "'is a gas discharge lamp that uses an electric arc through vaporized mercury to produce light. 25. :To'dim'discharge lamps you need to reduce the current through them without going below the striking voltage of the tube. 26. This effect later became the basis of the gas-discharge lamp , which led to neon lighting and mercury vapor lamps. 27. High-intensity discharge lamps ( HID) 28. These lamps are a form of discharge lamp where a small current causes a gas in the tube to glow. 29. In other conventional gas discharge lamps , the electrodes are the part with the shortest life, limiting the lamp lifespan severely. 30. Under certain conditions, the accumulated charge ( and hence the potential difference ) is sufficient to trigger a discharge lamp .
