What Do You Know About Miniature Lamps?

Did you know that your torchlight has a lamp called a miniature lamp?

A Miniature lamp refers to a lamp or a unit that ranges from ”grain of wheat” lamp to car headlights. Miniature in this sense is more indicative of low operating voltage rather than the physical size. In terms of voltage, a miniature lamp is rarely over 28 volts and often can be a little as 1.5 or 2.5 volts.Speciality Bulb - Miniature Lamps - July 2013800px-Honda_Insight_Concept_01


This type of lamp is specifically designed for applications where size, watts, amps, or voltage are specifically required. These lamps are usually inexpensive and have a long life cycle. They can be found in applications ranging from toys to lighting the aircraft’s instrument panel. They are ideal for applications that require higher light output or higher temperature operation than what is available from LEDs or light emitting diodes.


The filament for a miniature or subminiature lamp may be a straight wire (S), a coil (C), or a coiled coil (CC). The filament’s length is shortened by coiling the filament wear in order to be accommodated in a smaller-sized bulb. In gas-filled lamps, a coiled filament wire effectively reduces thermal losses and increases the efficiency of the lamp.

Tungsten FilamentSpecialty Bulb - Miniature Lamps July 2013450px-General_Electric_Mazda_B_electric_light,_ductile_tungsten_filament,_c._1910-1915_-_DSC06553

The most used filament material is tungsten. The reason for this is because tungsten has a high melting point at incandescence. The number following the coil identification letter denotes the filament arrangement on the supports.


These are the parts which provide electrical contact to the lamp. Other than this, the bases also provide support for the lamp in the fixture. For miniature and subminiature lamps, wedge bases or bayonet base types are more preferred over the screw base types especially if application has vibration. Wedge bases decreases the socket complexity and size. On the other hand, collared bases or flanged “bases” are generally associated with requirements for filament location.

Applications for Miniature Lamps

All standard miniature lamps comply with ANSI standard as when application requires. The most common applications for a miniature or subminiature lamp include:

  • automotive
  • toys
  • portable lighting (torchlight, lanterns, flashlights)
  • marine
  • aviation (aircraft panel instrument)
  • medical
  • industrial
  • scientific applications

Small Bulb for a Big Job

A miniature lamp is used for any application that requires a smaller bulb but a bigger lighting demand. The emergence of LEDs allowed smaller lamps to have much brighter illumination than the usual incandescent or other non-LED bulb or lamp.


Do you know of other applications for the miniature lamp?