The simplest and most energy-consuming is the incandescent lamp. Its working principle is electricity - > heat - > light.
Self-ballast lamp is similar to ballast lamp. The difference is that its ballast element is in the bulb. Like incandescent lamp, the lamp port is easy to install and has higher efficiency than incandescent lamp.
Ballast lamp: high pressure mercury lamp/high pressure sodium lamp.... The working principle is the same as fluorescent lamp, with ballast current limiting, auxiliary starter starting, the efficiency is higher than self-ballast lamp. At present, street lamp is mostly this kind of lamp.
Tungsten iodide lamp: Tungsten filament is installed in the iodine-containing lamp tube with long tubular shape and electrodes at both ends. Its working principle is the same as that of incandescent lamp, but it has high power, high heat and of course high brightness.
High-power energy-saving lamps, needless to say, have the same angle as incandescent lamps. They are easy to install and have high efficiency. The disadvantage is that the power is not too high.
I haven't touched the searchlights of the park landscape and the searchlights for air defense. There may be other forms of searchlights as well! _________
The purpose of lighting is to meet people's needs. In general, the first thing to consider when designing is whether it can meet the needs of work/production, and then whether it can save energy.