A Stroboscope is also known as strobe. A stroboscope is a test equipment which is utilised for making a cyclical rotating thing appearing to be slow moving or still. In other words, we can say that a Stroboscope is a monitoring and measuring device which uses stroboscopic effects for the observation of rapid periodic motions.

A view of stroboscope

A stroboscope has various uses, such as :

  • It is used to measure the oscillation frequencies of mechanical and electronic systems

  • It is used to measure resonance frequencies

  • It is used to study the vibrations of various bodies

  • It is used to visually monitor rapidly moving parts of machines.

Principle of Operation:

A stroboscope uses a flash lamp which is driven by an electronic oscillator. The flash lamp used is usually a xenon bulb, although LEDs are also used sometimes. The oscillator triggers the lamp at a steady rate of flash. The rate of flash can be varied and has a variable range from a few times per second to thousands of times per second. The flash lamp also consists  a reflector to increase its brightness and to make the flash more directional.

There are two basic types of stroboscope available :

  • General purpose Stroboscope– used for entertainment
  • Scientific Stroboscope – used for scientific or experimental purpose.

The entertainment / party models are speed-limited and have low cost. The rate of flash for entertainment purpose stroboscope is generally limited as it has been found that flashes at certain rates can induce epileptic seizures in some people. They may have some additional features like multiple colored lights (that flash in a sequence).  The scientific models don’t have any such speed limits. They must be able to capture high-speed periodic motions.

Scientific or professional strobes may also have some external trigger inputs. The external trigger overrides the internal oscillator. With the help of these external trigger inputs, one can easily sync the stroboscope to a moving machinery and slow down its motion for experiment/study.