1、EIA 268 63 M 323466161 U063673 3 R ,- 1 JANUARY, 1963 I EIA STANDARD on INFRARED -FILTER TRANSMISSION ELECTRONIC INDUSTRIES ASSOCIATION STANDARD RS-268 Formulated by JEDEC Plecfron Tube Council Y II II EIA 2b 63 3234680 00b3674 5 W NOTICE These standards, adopted and issued by the Electronic Industr
2、ies Association, were formulated by the Electron Tube Council of the Joint Electron Device Engineering Councils. EIA engineering standards are designed to serve the public interest through eliminating mis- understandings between manufacturers and purchasers, facilitating interchangeability and impro
3、ve- ment of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence of such standards shall not in any respect preclude any member or non-member of EIA from manufacturing or selling products not conforming to such stan
4、dards. Recommended standards adopted by EIA are without any regard to whether or not their adop- tion may in any way involve patents on articles, materials, or processes. By such action, EIA does not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adop
5、ting the recommended standards. Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 11 West 42nd Street, New York 36, N. Y. 0 Electronic Industries Association 1963 ail rights reserved Printed in U.S.A. - EIA 2b b3 W 3234600 0063b75 7 W INFRARED-FILTER TEhANSRIISSION (From EIA Stan
6、durds Proposal No. 690* formulated under the cognizance of JEDEC Committee JTS-8 on Photosensitive Devices) 1. PURPOSE The purpose of this standard is to establish the transmission of an infrared filter for use in making certain measurements on electron tubes. It is entirely feasible that additional
7、 infrared-filter standards will be proposed in the future as industry finds them to be necessary. 2. STANDARD The infrared-filter transmission, T(h), as a function of the wavelength of incident radiation at 25C shall be as tabulated in Table 1, and/or as plotted in Curve I. The tabulated, and/or plo
8、tted values, are provided by an infrared filter, such as Corning Filter, Glass Code No. 2540, Melt 1613, 2.62 mm thick. TABLE 1 Wavelength of Incident Radiation Microns 0.800 0.825 0.850 0.875 0,900 0.925 0.950 0.975 1.000 1.025 1.050 1.075 1.100 1.125 1.150 1.175 1.200 1.225 1.250 TransmGsion T(h)
9、ut 25C Percent 0.5 1.2 3.5 8.1 14.0 23.5 33.0 41.2 50.7 57.4 63.0 67.3 70.7 73.4 75.4 76.8 77.8 78.3 78.8 RS-268 Page 1 EIA 2bB 63 m 3234600 00b3b7b 9 m RS-268 Page 2 APPENDIX In testing specific types of infrared image-converter tubes for conversion index, use is made of an infrared filter having t
10、he transmission T(x) as prescribed in this standard. Conversion index which is a measure of the infrared sensitivity of the tube is defined as : Where Fe = the total available luminous flux emitted by the phosphor screen. Fi = the unfiltered (2870“ K color temperature tungsten lamp) flux incident on
11、 the photo- cathode of the tube. T= the filter factor of the infrared filter interposed between the light source and the photocathode. The path between the light source and the filter should not contain more than 0.1 cm of precipitable water vapor. T is defined by the following equation : Jorn R(h)
12、J(h) “(A) Sow R(x) JW dh T= Where R(h) = the relative response of the image-converter tube. J(x) = the relative spectral factor of the 2870“ K color temperature tungsten lamp light source. T(A) = the transmission of the infrared filter. c EIA 268 63 W 3234600 0063677 O = RS-268 Page 3 O i l O I I e
