dimmer

A dimmer is a device that controls the brightness of a light. In stagecraft, dimmers are crucial for adjusting the intensity of stage lights.12

There are two main types of dimmers: mechanical and electronic. Mechanical dimmers, like the early resistance dimmer, require physical manipulation to adjust current flow. Electronic dimmers use a low-voltage system to control current in a high-voltage circuit, allowing for remote operation.2

Early electronic dimmers, such as the thyratron tube dimmer, used a gating principle of rapidly turning current on and off. This paved the way for silicon-controlled rectifier (SCR) dimmers, which became the standard in stage lighting by the 1960s. SCR dimmers operate with a very fast on-off cycle, imperceptible to the human eye, to regulate light intensity.2