Phototropic Modulator

The action of phototropic Q-switches is based on the resonance absorption of radiation by solutions of organic dyes or glasses mixed with cadmium sulfide. These substances almost completely absorb a weak luminous flux, but with an increase in its intensity they become almost transparent. This happens because radiation photons that have arisen in the active medium spend all their energy on the excitation of atoms of matter, transferring them to a higher metastable level. As soon as the number of atoms at the upper and lower levels is approximately equal, the absorption ceases and the quality factor of the resonator is restored. In about a millisecond (${\displaystyle {\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">ten</span></span>}}^{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">-</span></span>\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">3</span></span>}}}$ {\ displaystyle {10 ^ {- 3}}} c) the atoms return to their ground state and the shutter is ready for operation again. The phototropic modulator allows you to receive pulses of the duration of the order${\displaystyle {\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">ten</span></span>}}^{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">-</span></span>\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">ten</span></span>}}}$ {\ displaystyle {10 ^ {- 10}}} ÷${\displaystyle {\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">ten</span></span>}}^{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">-</span></span>\mathrm{<span\; class="mwe-math-element"><span\; class="mwe-math-mathml-inline\; mwe-math-mathml-a11y"\; style="display:\; none;">12</span></span>}}}$ {\ displaystyle {10 ^ {- 12}}} seconds. ^[one]