Fresnel lens blind area viewers for improved mine equipment safety and productivity
By: by Guy A. Johnson.
Series: Information circular ;; 8950; Information circular (United States. Bureau of Mines) ;; 8950.
Publisher: U.S. Dept. of the Interior, Bureau of Mines
Published: 1983
Place of publication: [Avondale, Md.]
Language: eng
Number of pages: 15
Subjects: Mining machinery -- Blind-area viewers.; Fresnel lenses.
Notes: Includes bibliographical references.