In 1985, the famed physicist Richard Feynman offered an award of $1,000 for the first person or team able to print an entire page of a book on a surface small enough to fit on the head of a pin.
That feat was accomplished in 1985, when Tom Newman, a graduate student at Stanford University, printed the first page of "A Tale of Two Cites" in print small enough to win the prize. Now, an inkless printer developed by researchers from Missouri University of Science and Technology (S&T) uses holes instead of ink to produce tiny text and images.
Researchers created a microscopic version of the Missouri S&T athletic logo, measuring roughly 39-billionths of an inch across. This printer produces extremely small print that cannot be read without the use of a microscope.
The design was created on a surface similar to that of a household mirror, which the printer implanted with thousands of ultratiny holes. Instead of being manufactured from a single sheet of processed wood pulp, this specialty paper is composed of three layers. The middle layer is silica, sandwiched between two layers of silver.
Holes are drilled in precise patterns, to specific depths, in order to create microscopic wells designed to reflect light at specific wavelengths to produce desired colors. A light was then shone into the holes, producing the ultratiny letters and images.
"Unlike the printing process of an inkjet or laserjet printer, where mixed color pigments are used, there is no color ink used in our structural printing process - only different hole sizes on a thin metallic layer," said Dr. Jie Gao of Missouri S&T.
The idea of printing letters and words in microscopic printing may seem like a novelty idea, with no practical purpose. However, the methods used in this process could help design a new generation of more efficient computer processors, as well as other uses.
Tiny print has been used for decades for storage of information. One of the oldest of modern-day techniques is microfilm. Used by spies in World War II to record information from enemy plans and notes, it is still in use today at the National Archives due to its long life expectancy and the ease with which it can be read.
The development of the new ultrafine printing technique was detailed in the journal Scientific Reports.
