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© Dr. Rüdiger Paschotta
Last update: 2009-10-04
Quantum EfficiencyDefinition: percentage of input photons which contribute to a desired effect
The quantum efficiency (or quantum yield) is often of interest for processes which convert light in some way. It is defined as the percentage of the input photons which contribute to the desired effect. Examples are:
- In a laser gain medium, the pump process may require the transfer of laser-active ions from one electronic level (into which the ions are pumped) to the upper level of the laser transition. This pump quantum efficiency is the fraction of the absorbed pump photons which contributes to the population of the upper laser level. This efficiency is close to unity (100%) for many laser gain media, but can be substantially smaller for others. It may depend on factors like the excitation density and parasitic absorption processes.
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What are semiconductor diode laser describe with energy band diagram the construction and working of a semiconductor diode laser?
construction and working of semiconductor laser
What is the effect of temperature on photodiode?
photodiodes are basically reverse biased diodes with optical windows that allow like to shine on the PN junction. Like any diode, the leakage current (otherwise known as a photodiodes 'dark' current) increases exponentually with temperature in accordance to William Shockley's idea diode eqation. The other effect in a photo diode is the probability of a photon of a certain energy allowing an electron to cross the PN junction. This is known as the quantum efficiency of the photodiode. Because increasing temperatures increase the vibration of the silicon atoms, making them easier to be knocked loose by a photon. Thus the quantum efficiency of a photodiode will increase with tempature, as well as the thermally induced noise. photodiodes are basically reverse biased diodes with optical windows that allow like to shine on the PN junction. Like any diode, the leakage current (otherwise known as a photodiodes 'dark' current) increases exponentually with temperature in accordance to William Shockley's idea diode eqation. The other effect in a photo diode is the probability of a photon of a certain energy allowing an electron to cross the PN junction. This is known as the quantum efficiency of the photodiode. Because increasing temperatures increase the vibration of the silicon atoms, making them easier to be knocked loose by a photon. Thus the quantum efficiency of a photodiode will increase with tempature, as well as the thermally induced noise. photodiodes are basically reverse biased diodes with optical windows that allow like to shine on the PN junction. Like any diode, the leakage current (otherwise known as a photodiodes 'dark' current) increases exponentually with temperature in accordance to William Shockley's idea diode eqation. The other effect in a photo diode is the probability of a photon of a certain energy allowing an electron to cross the PN junction. This is known as the quantum efficiency of the photodiode. Because increasing temperatures increase the vibration of the silicon atoms, making them easier to be knocked loose by a photon. Thus the quantum efficiency of a photodiode will increase with tempature, as well as the thermally induced noise.
What kind of laser diode does a Casio projector use?
Most of the Casio projectors use a 445nm laser diode that is rated at 1 watt. The projectors have the diodes running at 600mw for life.
What does the nm in 650nm laser diode mean?
"nanometer" or billionths of a meter. 650 nanometers is the wavelength of the light produced by the diode.
What is the disadvantage of gunn diode?
Gunn Diodes are used in high frequency electronics. The advantages are increased efficiency and improved temperature stability while a disadvantage is the Gunn Diode can get burned out.
What type of laser is a diode laser?
A diode laser. Also, a continuous wave laser.A diode laser. Also, a solid state laser.A diode laser. Also, a high efficiency laser, comparing to other types of laser.It's a semi-conductor laser
Which is better light emitting diode or laser diode?
Laser diode
Which is better injection laser diode or light emitting diode?
Laser diode
Is a diode laser a nd. yag laser?
No, a diode laser and an Nd:YAG laser are two different types of lasers. A diode laser uses a diode as the laser medium and is commonly used for various applications such as hair removal and skin treatments. On the other hand, an Nd:YAG laser uses neodymium-doped yttrium aluminum garnet as the laser medium and is often used for medical and cosmetic procedures, as well as in industrial applications.
What are semiconductor diode laser describe with energy band diagram the construction and working of a semiconductor diode laser?
construction and working of semiconductor laser
Do they use a laser in an optical mouse?
Yes, that is a laser diode
When is a laser diode module a useful thing to have?
A laser diode module is useful when a small laser with lower power usage is needed. The diode is used in a multitude of fields, including life science, industrial, and scientific instrumentation.
Is a laser pointer a ruby laser?
Not usually. Laser pointers are usually diode lasers.
Where can one purchase laser diode modules?
One can purchase laser diode modules on select places around the Hong Kong. OPELUS is the best place to purchase laser diode Modules, Infrared Laser Module, Green Laser Module etc.
What is laser beam?
When one remove the focusing barrel of the laser diode.
Television signals are converted into light signals by?
Laser Diode. photo diode
Can a blue laser diode be safely and effectively connected to a green laser diode driver?
This would depend on the diode's specifications but it would be very unlikely because blue laser diodes require less voltage and current then green lasers.
