Research on Q-Switched Nd : YAG laser engraving

IN this paper, the engraving process with Q-Switched Nd:YAG laser is investigated. High power density is the pre- requisition to vapor materials, and high repetition rate makes the engraving process highly efficient. An acousto- optic Q-Switch is applied in the cavity of CW 200 W Nd:YAG laser to achieve the high peak power density and the high pulse repetition rate. Different shape craters are formed in a patterned structure on the material surface when the laser beam irradiates on it by controlling power density, pulse repetition rate, pulse quantity and pulse interval. In addition, assisting oxygen gas is used for not only improving combustion to deepen the craters but also removing the plasma that generated on the top of craters. Off-focus length classified as negative and positive has a substantial effect on crater diameters. According to the message of rotating angle positions from material to be engraved and the information of graph pixels from computer, a special graph is imparted to the material by integrating the Q- Switched Nd:YAG laser with the computer graph manipulation and the numerically controlled worktable. The crater diameter depends on laser beam divergence and laser focal length. The crater diameter changes from 50 micrometers to 300 micrometers , and the maximum of crater depth reaches one millimeter.

Charles Clarke Chapman, portrait engraving

Engraved portrait of Charles Clarke Chapman, in book produced by the Historic Record Company, ca. 1911.

Receipt from Tiffany and Co., New York for engraving on a seal

Receipt from Tiffany and Co., New York for engraving on a seal, Oct. 9, 1884

Artists at home : photographed by J. P. Mayall, and reproduced in facsimile by photo-engraving on copper plates /

Mode of access: Internet.

Photo-engraving; a practical treatise on the production of printing blocks by modern photograhic methods.

Mode of access: Internet.

Modern etching and engraving /

Most of the plates printed on both sides.

Tools and materials used in etching and engraving; a descriptive catalogue of a collection exhibited in the museum.

At head of title: Victoria and Albert museum. Department of engraving, illustration and design.

The artist's assistant in drawing, etching, engraving, mezzotinto-scraping, painting on glass, and on silks, satins, &c. : containing the easiest and most comprehensive rules for the attainment of those truly useful and polite arts /

Mode of access: Internet.

Green-wood illustrated : in highly finished line engraving, from drawings taken on the spot /

Avery Classics (Offsite) copy: Signed "Josephine Doughine" and bound in cover with imprint "Josephie Dougherty"; stamped "Whitlock."

A bibliography of American books relating to prints and the art and history of engraving:

Mode of access: Internet.

French portrait engraving of the XVIIth and XVIIIth centuries,

Lists of French portrait engravers and painters: p. 175-211.

A descriptive catalogue of an exhibition of early engraving in America, December 12, 1904 - February 5, 1905.

Mode of access: Internet.

Sketch of the life and work of Linda Gilbert, with statistical reports and engraving of herself.

Mode of access: Internet.

A compendium of modern geography : with remarks on the physical peculiarities, productions, commerce, and government of the various countries : questions for examination at the end of each division : and descriptive tables, in which are given the pronunciation, and a concise account of every place of importance throughout the world : illustrated by ten new maps, and an engraving, showing the heights of the principal mountains on the globe /

Mode of access: Internet.