TABLE 560.— SOME BAUSCH & LOMB LIGHT FILTERS* 



537 



Percent transmission for a number of wavelengths. All values are for a thickness of 

 3.5 mm unless otherwise noted. The values given include surface reflection losses. All 

 glasses except the sharp cutting reds and yellows will meet the standard value at 3.5 mm 

 within a thickness range of 3.0 to 4.0 mm. The sharp cutting reds and yellows will meet the 

 standard value at 3.5 within a thickness range of 2.0 to 6.0 mm. 



* Adapted from data furnished by J. W. Forrest, Bausch & Lomb Optical Co. 

 t t = 2.0 mm. 



TABLE 561.— SPECTRAL TRANSMISSION OF SOME RED PYROMETER GLASSES 



Glass 



Jena 4512 



Jena 2745. 



Corning high trans- 

 mission red : 

 150 percent. . . 5 

 50 percent. . . 5 

 28 percent ... 6 



Thickness 

 mm 



.. 2.93 

 3.2 



Wavelengths fi 



.60 .61 .62 



.8 2.5 



.1 4.7 



38.5 



.1 



.63 



1.8 

 6.5 



64.3 

 5.5 



.64 



25.0 

 10.5 



72.2 



44.5 



2.0 



.65 



57.0 

 13.8 



76.5 

 66.5 

 24.0 



.66 



67.4 

 18.0 



79.3 

 74.2 

 67.0 



.67 



72.3 

 22.3 



80.8 

 76.5 

 73.8 



75.5 

 26.0 



87.5 

 77.8 

 76.8 



.70 



78.5 

 33.5 



80.8 

 77.5 

 76.2 



.72 



80.5 

 39.5 



78.5 

 76.3 

 75.1 



81.0 

 44.5 



77.0 

 75.5 

 73.2 



.76 



81.5 

 47.5 



75.0 

 74.1 

 71.8 



TABLE 562.— THE EFFECTIVE WAVELENGTH X e OF CORNING 50-PERCENT 

 RED PYROMETER GLASS* 5 mm THICK FOR SOME TEMPERATURE 



INTERVALS 186 



* See Table 77. 



laa "Temperature, Its Measurement and Control,' 

 of Physics, p. 1115, Reinhold Publishing Co. 



a symposium prepared by the American Institute 



SMITHSONIAN PHYSICAL TABLES 



