This is a way to make three dimensional holograms without lasers or special equipment. It uses stuff you already own, and the results are astounding. Bill Beaty shows us some examples in the video above. Here is a great page with pictures about how he stumbled upon the phenomenon one day out on a walk and pioneered the technique, and another page with detailed instructions. The technique relies upon the effect you see in very fine circular scratches on a shiny material (like car paint), where the reflection appears to form a straight line. By varying the location of the circles, you set the locations of the lines, and by varying their diameter, you vary their apparent depth.
Update: Reader Lali has noted that the above links aren’t working, so I’ll post a summary of the process:
- Start with a material that can be scratched in a way that will create shiny scratches. A CD jewel case is a good first project.
- Down at the very bottom of the material (or on something below and attached) do a small sketch of the object you want to make a hologram of. Something simple. I started with a cube and it was a bit tough for a first try, but it taught me what I needed to know. I’ll use it as an example.
- using an adjustable circle drawing compass or something similar, put one point at the top point of your cube sketch and drag the other across near the top of the CD case to create a scratch arc. When you turn it near a point source of light, you should see a reflected point of light in the scratch that moves when you tilt the jewel case.
- The 3D depth of the final hologram corresponds to the spacing between the compass points. repeat the above scratch process for the other points of the cube, setting the compass spacing closer for the closer portions of the cube, and farther for the more distant.
- Set the bottom point at regular intervals along any lines that are going to be at the same 3D depth in the final hologram and continue making scratch arcs. For lines angling into the distance, you can just set your lower compass point at the midway point of the line in the sketch and set the spacing to fall between the lines you scratched for the endpoints. Continue this at regular intervals down the line. Your reflected points will now become reflected lines, complete with depth.