Carlson graduated from the physics department of the University of California, and worked in Bell Telephone Research Institute from 65438 to 0930, and later transferred to the patent department of the institute. After a period of study, he obtained a doctorate in law. New york's telephone number is 1934. Mallory Electronics Company is a patent lawyer. In practical work, sometimes a document needs to be copied in multiple copies, but it is usually handwritten, which is time-consuming and laborious, and the quality cannot be guaranteed. So, is there any way to save time and effort? He thought of inventing the copier: put the document to be copied on the machine, press the button, and the same document will come out in the required number of copies.

With this goal in mind, from 65438 to 0935, 29-year-old Carlson and his assistant Otto Kony started their research in the temporary laboratory, but the previous times ended in failure. In order to find a shortcut to success, with the overall goal of "improving replication technology", he spent most of his spare time of three or four years consulting patent documents in the National Library of new york.

Through systematic and patient browsing, he finally found some patent specifications about replication technology. Through the analysis of these documents, he found that the previous methods were wet chemical method or mechanical method-copying multiple photos with photographic negatives is one of wet chemistry. The disadvantages of these methods are slow copying speed and high cost. So, can we use physical methods, such as optics and electricity, to overcome these shortcomings and complete replication?

So, Carlson and Kony started a new round of experiments, and finally invented the dry electrostatic copier according to the principle of mutual attraction of heterogeneous charges, and applied for the patent of "electrostatic photography" in 1937, and the patent granted time was 1942 10.06.

193810122-38 in an ordinary workshop in Queens, new york, Carlson and Kony wrote the words "Artoria 10-22-38" on a glass plate with ink. Then, they wiped the metal plate coated with sulfur with cloth handkerchiefs to make it charged, and then exposed the metal plate to floodlight for 3 seconds through a glass plate with words written on it-the original words were displayed on the plate. In this way, the world's first reproduction painting was born. This small picture is only 5 square centimeters, and it is printed with "Artoria 10-22-38". Today, this little piece of paper has become a precious cultural relic. The world's first electrostatic copier was born. He also obtained two patents for an electrostatic copier on1April 4, 939 and 1654381October 6, respectively.

Carlson