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  2. Laser pointer - Wikipedia

    en.wikipedia.org/wiki/Laser_pointer

    Red (635 nm), blueish violet (445 nm), and green (520 nm) laser pointers. A laser pointer or laser pen is a (typically battery-powered) handheld device that uses a laser diode to emit a narrow low-power visible laser beam (i.e. coherent light) to highlight something of interest with a small bright colored spot.

  3. Speckle (interference) - Wikipedia

    en.wikipedia.org/wiki/Speckle_(interference)

    A green laser pointer. Reduction of the speckle was necessary to photograph the laser's Gaussian profile, accomplished by removing all lenses and projecting it onto an opaque liquid (milk) being the only surface flat and smooth enough. Speckle is considered to be a problem in laser based display systems like the Laser TV. Speckle is usually ...

  4. Frequency comb - Wikipedia

    en.wikipedia.org/wiki/Frequency_comb

    A frequency comb or spectral comb is a spectrum made of discrete and regularly spaced spectral lines.In optics, a frequency comb can be generated by certain laser sources.. A number of mechanisms exist for obtaining an optical frequency comb, including periodic modulation (in amplitude and/or phase) of a continuous-wave laser, four-wave mixing in nonlinear media, or stabilization of the pulse ...

  5. List of laser types - Wikipedia

    en.wikipedia.org/wiki/List_of_laser_types

    Laser types with distinct laser lines are shown above the wavelength bar, while below are shown lasers that can emit in a wavelength range. The height of the lines and bars gives an indication of the maximal power/pulse energy commercially available, while the color codifies the type of laser material (see the figure description for details).

  6. Wireless clicker - Wikipedia

    en.wikipedia.org/wiki/Wireless_clicker

    A speaker giving a presentation with an RF pointer in his left hand. Using a wireless clicker, helps the presenter to move freely, instead of being obliged to stay next to the computer, can get closer and keep in touch with the audience, watching the presentation together with them, being able to use the built-in laser pointer, in order to emphasize specific points in the dialogue with the ...

  7. Acousto-optic modulator - Wikipedia

    en.wikipedia.org/wiki/Acousto-optic_modulator

    An acousto-optic modulator (AOM), also called a Bragg cell or an acousto-optic deflector (AOD), uses the acousto-optic effect to diffract and shift the frequency of light using sound waves (usually at radio-frequency). They are used in lasers for Q-switching, telecommunications for signal modulation, and in spectroscopy for frequency

  8. Frequency-resolved optical gating - Wikipedia

    en.wikipedia.org/wiki/Frequency-resolved_optical...

    Frequency-resolved optical gating (FROG) is a general method for measuring the spectral phase of ultrashort laser pulses, which range from subfemtosecond to about a nanosecond in length. Invented in 1991 by Rick Trebino and Daniel J. Kane, FROG was the first technique to solve this problem, which is difficult because, ordinarily, to measure an ...

  9. Diode-pumped solid-state laser - Wikipedia

    en.wikipedia.org/wiki/Diode-pumped_solid-state_laser

    The most common DPSSL in use is the 532 nm wavelength green laser pointer. A powerful (>200 mW) 808 nm wavelength infrared GaAlAs laser diode pumps a neodymium-doped yttrium aluminium garnet (Nd:YAG) or a neodymium-doped yttrium orthovanadate (Nd:YVO 4) crystal which produces 1064 nm wavelength light from the main spectral transition of ...