| 摘要 |
A method for printing braille characters by means of a lithographic printing process in which photosensitive sheet material is exposed to form a dot image of one or more braille characters on the sheet material. The sheet material is then developed and subsequently photographed and a negative made of the developed sheet material. The negative is stripped onto a goldenrod sheet and the stripped negative is exposed on a light-sensitive lithographic plate which is subsequently developed. The dot image developed on the lithographic plate is then offset printed on sheet material stock and the printed sheet stock is passed through a thermography machine to form raised braille characters on the sheet stock.
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