. Elementary and dental radiography / by Howard Riley Raper . he glass of the tube gives riseto a green fluorescence (green light) in the active hemisphere—the hemi-sphere in front of the target—of the tube. Whether a tube is workingwell or not can be determined by this fluorescence. There should be adefinite line of demarcation between the active and inactive hemispheresof the tube. A tube working properly should light up as per Fig. light is never quite steady; it wavers a little. High, medium andlow tubes give slightly different fluorescences when in operation. Thefluorescence from a
. Elementary and dental radiography / by Howard Riley Raper . he glass of the tube gives riseto a green fluorescence (green light) in the active hemisphere—the hemi-sphere in front of the target—of the tube. Whether a tube is workingwell or not can be determined by this fluorescence. There should be adefinite line of demarcation between the active and inactive hemispheresof the tube. A tube working properly should light up as per Fig. light is never quite steady; it wavers a little. High, medium andlow tubes give slightly different fluorescences when in operation. Thefluorescence from a high tube is a very light yellowish green ; from a low *Custers Dental Electricity. 52 ELEMENTARY RADIOGRAPHY . tube a bluish green and from a medium tube an intermediate shade ofgreen. Just here let it be said that an exact colored picture of an X-raytube in operation has never been made. I obtained the services of anartist and spent a great many hours on the work, but was unable to makea picture worthy of reproduction. The light from an X-ray tube in. Fig. 50. Patent series or inverse spark gap for positive terminal. operation is of a peculiar brilliancy that cannot be reproduced in crayons,water-colors, or ink. When the vacuum of a tube is so low as to render it useless for radio-graphic purposes, a definite blue color can be seen here and there in thetube, the cathode stream can sometimes be seen appearing blue, and theline of demarcation between the active and inactive hemispheres of thetube is not well defined. When a tube is punctured the vacuum gets very low, of course, andits appearance in operation may be as just described, or, as sometimesoccurs, it gives rise to a fluorescence as variegated as a rainbow, or it maynot light at all. A punctured tube can sometimes be repaired by themanufacturer. When the vacuum of a tube is too high, the tube lights up reluctantlya very yellowish green, and the line of demarcation is not at all distinct. Fig. 48 illustrates fairly
Size: 1923px × 1299px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., book, bookauthorraperhowardriley, bookcentury1900, bookdecade1910
