At the processing plant, the letter is sent through a machine that rapidly separates mail by shape, separating letters from large envelopes and packages, which is called the culling operation. The machine adjusts letters so that all the addresses face the same way and are right side up.
A postmark is then applied with the date and place where the letter was sorted. Each letter is also identified by a code consisting of a series of florescent bars imprinted on the back. An optical character reader scans the address on the front of each letter. Images of letters that could not be successfully read are transmitted to a remote encoding center for further processing.
All letters are then placed in trays and moved to the next piece of automated equipment for barcode application. Linked with the identification code, a barcode is sprayed on the front of the letter. The barcode, representing the specific delivery address, consists of tall and short bars used for further sorting.
Already a subscriber? Sign in. Thanks for reading Scientific American. Create your free account or Sign in to continue. See Subscription Options. Discover World-Changing Science. When did the postal service start relying on these machines? When did the machines start sorting packages as well as letters?
Get smart. Sign up for our email newsletter. Sign Up. All who need to ship items to out-of-town clients or colleagues know the importance of reliable and timely shipping services. The U. Postal Service is one of those services; like similar services, the USPS lets you track your shipped packages online via a tracking number. A key part of this shipping and tracking process is the "Sorting Completed" phase. Mobile Newsletter chat dots. Mobile Newsletter chat avatar.
Mobile Newsletter chat subscribe. Prev NEXT. How the U. A mail box shows the times of collection. Cite This!
0コメント