Make a wish ...

Click on this image, cross your eyes and make a wish ...




Most readers will probably recognize this one right away as an autostereogram (also
called Magic Eye), a popular fad in the 1980s and 1990s. Autostereograms are computergenerated images which when viewed with crossed eyes, appear as a vivid threedimensional image magically suspended in mid-air.
So if you have not yet seen the image hidden in the picture, please give it a crack now. It works best if you place your face about 30 cm from the image and then cross your eyes until an image appears. Make sure to make a wish before doing so.
If you don't know how to cross your eyes, see this.
The scientific explanation for how Magic Eye images work is rather simple. The image
consists of a series of repeating patterns. For the type of autostereogram that I used in the comic, the image appears as a random set of dots when viewed normally. However, when a viewer looks at the image at close distance while crossing her eyes at just the right angle, each of her eyes are fixed on a different set of an adjacent pair in the repeating pattern and her brain mistakenly perceives the two patterns as a single image at a different distance.