Introduction: Fake Crookes Tube.
I wanted a decorative device that looks like a working Crookes tube, but does not emit harmful x-rays.
Step 1: Theory.
If you use photons instead of electrons, but replicate Crookes tube geometry, the generated image will be similar to original. See the diagram.
Even though it is fake, it is not digital. It generates image using fully analog methods, just like original does.
I invite Chinese engineers to read this. :)
Step 2: Results.
Here's what I got. Note that it is a prototype, proof of concept, that's why it looks so ugly. When you build it, you can make it look better. Also camera sensor overloading made image borders look blurred.
Step 3: Simulating Deflection.
Unlike electrons, photons can propagate in air, but, of course, you cannot deflect them with magnet, like you would deflect electrons in a real Crookes tube. But you can simulate deflection by slightly moving the LED.
Step 4: Trying to Photograph It Better.
I tried to reduce camera sensitivity to show that in reality borders are not blurred, but sharp. Human eyes see them even sharper. It looks surprisingly realistic, resembling not only a Crookes tube, but also a 6E1P style tuning eye tube.
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