Holography Without Photography

Prof. Thad Walker has developed a simple method for generating Holograms using a personal computer and a laser printer. An image (usually a person’s name) is generated using a graphics program, and then a computer program calculates the hologram needed to reconstruct that image using a laser beam. Here’s an example of a hologram:

When this is printed on a standard overhead projector transparency, and placed in the following optical setup,

this image appears on the screen:

Here is a picture of the actual apparatus, being adjusted by a student.

On many occasions he has taken the apparatus to elementary and middle schools to get kids excited about making such holographic “codes”. It takes only a couple of minutes to make a hologram from scratch, so every student gets to take home their name “coded” in a hologram. In 2006 he received a “Distinguished Service Award” from Jefferson Middle School for his efforts.

Prof. Walker has adapted this procedure for use in our freshman physics laboratories, where students learn about diffraction by manipulating the holograms in various ways.