What is better than 100MHz oscilloscope? How about optics? Researchers at the University of Central Florida think it’s just a ticket. They have made an oscilloscope that can measure the electric field of light. You can find the full text on the Internet.
Because the frequency involved is very high, it is difficult to read the electric field of light with traditional tools. According to Michael Chini, who developed the new instrument, the speed of the oscilloscope is 10000 times faster than that of the traditional oscilloscope.
As you might expect, measuring several cycles of light requires some special techniques. According to the newspaper:
[A]n intense fundamental pulse with a central wavelength of 3.4 µm creates charge packets in the pixels of a silicon-based image sensor via multiphoton excitation, leading to detectable photocurrents. The probability of excitation is perturbed by the field of a weak perturbation pulse, leading to a modulation in the excitation probability and therefore in the magnitude of the detected photocurrent. We have previously shown that, for collinear fundamental and perturbation pulses, the dependence of the modulation in the excitation probability on the time delay between the two pulses encodes the time-varying electric-field waveform of the laser pulse. Here, by using a crossed-beam geometry with cylindrical focusing, we map the time delay onto a transverse spatial coordinate of the image sensor chip to achieve single-shot detection.
Do you understand In other words, they do not directly measure the optical pulse, but measure the change of the optical pulse to another known signal. We think
Unless you want to transmit high-speed data over optical fiber, we’re not sure if you really need it. However, this concept is interesting and has not been unheard of before. For example, we have seen a capacitance meter, which measures the frequency change caused by adding an unknown capacitance to an existing oscillator.
If you want something more traditional, you can take a look at some popular oscilloscopes. Of course, this high-speed thing may be able to apply time-domain reflectometer to optical fiber. Probably