很早的印表機專利

從一個產業來看專利
可以發現許多有趣的東西
尤其是有點歷史的科技

看看1974年IBM提出的一件印表機專利
揭露印表機中的訊號轉換
資料經過編碼, 傳遞至印表機, 轉成圖形碼（graphic code）或是透過查表的方式比對出欲列印出來的字元影像（character image）, 經過感光鼓（printing drum）的掃描列印

此案主要範圍利用means plus function來寫作

1. A system for printing characters in response to coded data comprising:

means for storing a plurality of different sets of graphical data, each set of graphical data being identified by a particular address and defining the portions of a grid pattern which a particular character comprises;

means responsive to receipt of the coded data by the system for assembling the data into a group representing a plurality of characters to be printed;

means responsive to assembly of the coded data into a group for translating each portion of the coded data representing a character into a corresponding address, the means for translating including means for storing addresses in a plurality of different storage locations and means responsive to the value of each portion of the coded data representing a character for selecting a storage location to provide the address stored therein;

means responsive to each address from the means for translating for selecting the corresponding set of graphical data from the means for storing sets of graphical data corresponding to the address;

grid pattern scanning print means; and

means responsive to each selected set of graphical data for modulating the scanning print means in accordance with the graphical data to print a character.

清楚看到列印系統包括儲存影像資料、轉換成可列印的字元、位址、根據位址轉換為要列印的影像資料、將欲列印的影像傳遞給印表機列印

Ron