The wavelength of the emitted light from a laser is determined by which of the following?
a.
the active medium's composition
b.
frequency of the amplifying radiation
c.
the lasing tube's length
d.
all of the above
To determine the wavelength of the emitted light from a laser, we need to consider several factors. The correct option among the provided choices is "d. all of the above."
Here's an explanation for each factor:
a. The active medium's composition: The composition of the active medium in a laser determines the energy levels of the atoms or molecules within it. When the atoms or molecules are excited by an external energy source, they release photons to transition to lower energy levels, emitting light in the process. The specific energy levels involved in these transitions determine the wavelength of the emitted light.
b. Frequency of the amplifying radiation: In a laser, an external energy source (such as an electric current or another laser) provides radiation to stimulate the emission of light. The frequency of this amplifying radiation is directly related to the wavelength of the emitted light according to the equation c = λf, where c is the speed of light, λ is the wavelength, and f is the frequency.
c. The lasing tube's length: The length of the lasing tube, which contains the active medium, can also affect the emitted wavelength. In some laser types, such as gas lasers, the length of the lasing cavity determines the resonance conditions for the emitted light. These resonance conditions determine the allowed wavelengths that can be produced.
Considering all three factors (the active medium's composition, frequency of the amplifying radiation, and the lasing tube's length) helps determine the wavelength of the emitted light from a laser.