Hand-Drawn Scratch Hologram

Scratch holograms are a type of hand-drawn hologram. Simply scratch out a bunch of circles onto a sheet of acrylic, hold it up to the light, and voilá, a 3D image appears!

This mysterious invention was first introduced by William J. Beaty on his website, where he also explained the underlying optical theory (see reference). Since then, others have built on his work to refine the design and deepen the theoretical understanding.

What amazes me most, however, is the elegance and simplicity of Beaty's original concept—you can create a scratch hologram by hand using just everyday materials.

Hard plastic sheet: I started with CD cases. For better contrast and visibility, I used a CD case with a black bottom and a clear lid. This video was made earlier as a proof of concept using a CD case. It's hard to see on the phone camera, but you can see an image moving back and forth across the CD case. However, a black acrylic sheet provides the best results and this is what I use in this Instructable.

Compass: For more precise scratches, use a compass with a center control wheel, which helps prevent the legs from shifting during use.

Tape: Used to secure your pattern to the plastic sheet.

Create a pattern you'd like to use—either draw it by hand or print it out. Then, tape the design securely to the back of your plastic sheet.

Here I chose the golden spiral.

With the pattern secured, use a pointed tool—like an awl or the tip of a compass—to trace the outline by making small dots spaced about 1/8 inch apart. Once you’ve completed the entire design, carefully remove the paper pattern from the plastic sheet.

Set the compass points to a fixed distance—this will determine how far in front of or behind the surface the resulting image will appear. Place one point of the compass on a dot from your pattern on the plastic sheet, and gently rotate the compass to create a scratch of full circle.

Be careful: you want to leave a visible, smooth mark without digging too deeply or producing white, dusty scrapes. The scratch should catch the light but remain clean and subtle. When you tilt the sheet under sunlight, you should see a bright point of light traveling along the arc—this is the key visual effect of a scratch hologram.

Note: The original scratch hologram technique relies on making arc-shaped scratches on a smooth surface. Generally, the longer the arc, the farther the virtual object appears to "travel" in space. Shorter arcs produce more localized effects. By drawing arcs in segments (or "chunks"), you can create the illusion of objects fading in and out. If you complete a full circle of arcs, the resulting effect may resemble an object rotating—though expect some distortion.

Tips:

To avoid smudging the surface, wear gloves while working.

Be patient! This will take a while, so put on some music if you want.

After you've finished scratching, clean the surface using compressed air or a gas duster to remove any debris.

View the scratched surface under direct sunlight. Face the sun and slowly tilt the plastic sheet in front of you. At a certain angle, you'll notice two additional images of your drawing: one appears to float above the surface, while the other seems to lie behind it. If you rotate the sheet, you will notice that your pattern is rotating, though it is distorted.

Have fun!