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1、E I A TEPIOS BI m 3234b00 O007440 8 m OCTOBER 1981 7 TEST CRITERIA . FOR X-RAY IMAGE INTENSIFIER TUBES FORMULATED BY EIA TUBE ENGINEERING PANEL ADVISORY COUNCIL (TEPAC) TEPAC PUBLICATION No. 109 (Revision of TEPAC Suggested Standard No. 9) Copyright Electronic Components, Assemblies & Materials Asso
2、ciation Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- E I A TEP307 83 W 3234600 0007443 T NOTICE EIA Engineering Standards and Publications are
3、designed to serve the public interest through eliminating misunderstandings between manufacturers and purchasers, facilitatirig interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existe
4、nce of such Standards and Publications shall not in any respect preclude any member or non-member of EIA from manufacturing or selling products not conforming to such Standards and Publications, nor shall the existence of auch Standards and Publications preclude their voluntary use by those other th
5、an EIA members, whether the standard is to be used either domestically or internationally. Recommended Standards and Publications are adopted by EIA without regard to whether or not their adoption may involve patents on articles, materials, or processes. By such action, EIA does not assume any liabi
6、lity to any patent owner, nor does it assume any obligation whatever to parties adopting the Recom- mended Standard or Publication. This document has been developed to recommend a standardized method of measurement of x-radiation from CRTS for tube manufacturer compliance with HHS Bureau of Radiolog
7、ical Health Regulations on this subject, Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 2001 Eye Street, N.W. Washington, D.C. 20006 .- PRICE: $5.50 Printed in U.S.A. Copyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Lic
8、ensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- c- -. E I A TEPLOS BL m 3234b00 00074i.12 L m TEPAC Publication No. 109 Paragraph 1.0 2, o 3.0 4 . 0 FIGURE 1 : FIGURE 2 : FIGURE 3: FIGURE
9、4: FIGURE 5: FIGURE 6: FIGURE 7: FIGURE 8: FIGURE 9: FIGURE 10: FIGURE 1 1 : APPENDIX I: APPENDIX I I : TEST CRITERIA FOR X-RAY IMAGE INTENSIFIER TUBES TABLE OF CONTENTS Purpose and Scope Definitions . Measurements Conversion Factor Useful Area and Field Diameter Useful Area (Calculated) X-Ray Test
10、Resolution Chart Radiation Meacuremen t Se t-Up Resolving Power Measurement Set-up Resolving Power Test Plot Contrast Test Phantom Radiation Measurement Set-up Contrast Measurement Set-up Radiation Measurement Set-up Output Screen Brightness Page 2 2 3 5 7 7 0 9 9 10 1 1 12 12 13 13 14 15 -1- - / Co
11、pyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- EIA TEPLOS 81 m 3234600 0007443
12、3 m I - TEST CRITERIA FOR X-RAY IMAGE INTENSIFIER TUBES EIA/TEPAC PUBLICATION NO. 109 PREFACE The material herein was developed b y the JT-4 Committee on Photosensitive Electron Tubes and previously issued in the form of a JEDEC suggested Standard entitled “Test Standard for X-Ray Image Intensifier
13、Tubes“ (JEDEC Suggested Standard No. 9, dated March 1969). a The document was transferred to the JT-20 Committee on Electro-Optic Devices who reaffirmed the publication for distribution under the cognizance of the EIA Tube Engineering Panel Advisory Council (TEPAC) as TEPAC Pub1 ication No. 109. Cop
14、yright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- E I A TEPLOS 81 = 3234b00 O007444
15、 5 1.0 1.1 2.0 O 2.1 2.2 2.3 2.4 2.5 TEST CRITERIA FOR X-RAY IMAGE INTENSIFIER TUBES Purpose and Scope .- This document provides recommended test methods for the measurement and ratings of X-ray image intensifier tubes. CAUTION: SAFETY CONSIDERATIONS Measuring instruments should be properZy grounded
16、. Cau-bion should be -taken to avoid shock hazard, particularly i n the vicinity of the anode connection and the voltage metering systems, . ment procedue. Safety glasses -should be worn at al2 times during the measure- X-ray f i l m badga skould be worn i n accordance with estabZishsd plant safety
17、practices for mon%torZng radiation dosage. Defini ti ons . . . X-ray Image Intensifier Tube - A vacuum tube containing an input screen which converts an X-ray pattern into an electron pattern and i n which the electrons are accelerated and focused on to an output screen which converts the electron p
18、attern into a light image of brightness greater than that of a fluoroscope screen, Useful Area - The area of the input plane enclosed by a circle having a radius over which the resolution is specified (see Fig.1). Useful Field Diameter - The diameter of the X-ray beam, measured at the location of th
19、e object, which produces an X-ray shadow covering the useful area (see Fig. 1). Image Quality - The faithfulness of the reproduction of an X-ray pattern (see definitions 2.8 and 2.9). Input Screen - The surface, either flat or curved, i n which X-radiation i s absorbed and in which the X-ray image i
20、s converted into either an image o f fluorescent light or of electric charge. Copyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo reproduction or netw
21、orking permitted without license from IHS -,-,- E I A TEPLOS BL m 3234600 0007445 7 m 2.6 2.7 2.8 2.9 2.10 3. O 3.1 3.1.1 3.1.2 3.1.3 Output Screen - The surface in which is located the phosphor which 9 displays a light image. Conversion Factor - The quotient of the brightness in foot lamberts (or c
22、andelas/m2) a t the output screen by the input radiation i n mR/minute. The P number phosphor of the output screen and the quality of the input radiation must be specified. 1 candela/m2 = 0.2919 foot lambert. 1 foot lambert = 3.426 candela/m2. Maximum Resolving Power - The number o f space and bar c
23、ombinations per c m (inch) of high x-ray contrast a t the entrance plane such that the bars still can be discerned visually as separate entities a t the output screen. Minimum Visible Contrast - The difference i n thickness of the X-ray absorption fil ter expressed as a percentage of the maximum thi
24、ck- ness that produces a perceptible difference in brightness on the output screen a t a specified exposure rate (see Fig. 7). The Entrance Plane - The plane i n front of the input screen, through which, according to the specifications of -the manufacturer, no part of the image intensifier will prot
25、rude (see Fig. 1). I ! , o Measurements - For the evaluation of an X-ray Image Intensifier, the fol lowing measurements chal 1 be made: 1) Useful Area 2) Image Quality 3) Conversion Factor The Useful Area Place an X-ray tube a t a distance of 71 cm entrance plane. 28 inches) from the Confine the X-r
26、ay beam i n order to irradiate exactly the useful area Measure the diameter o f the X-ray beam a t the entrance plane = a c m (inches). Copyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not
27、for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- O 3.1.4 3.1.5 3.1.6 3.1 7 3.2 3.2.1 O 3.2.2 E I A TEPLOS 81 3234600 0007446 9 Reduce the X-ray-tube-entrance plane distance to 35.6 c m (14 inches). Confine the X-ray beam i n order to irradiate
28、 exactly the useful area. Measure the diameter of the X-ray beam a t the entrance plane = b c m (inches). The diameter of the useful area can now be calculated by the for- mula D = ab/2b-a c m (inches), (see Fig. 2). The Image Quality per, X-ray Exposure Rate - This measurement is sub-divided into d
29、etermination of the maximum resolving power and minimum visible contrast. Maximum resolving power shall be measured w i t h a test phantom as indicated by Figure 3 and Appendix 1. The measurements shall be made as follows: (a) Radiation measuring Set-up (see Figure 4). (b) Measurements shall be done
30、 a t 60 KVP and the current adjusted i n order to produce an exposure rate of 100 mR per minute a t the entrance plane. (c) Resolving power measurement Set-up (see Figure 5). (d) Measurement of the resolving power shall be done w i t h a suitable optical means of sufficient magnification, i n the ce
31、nter, a t a 2.5 c m (1 inch) radius from the center, 5,l c m (2 inches), 7.6 cm (3 inches), etc., and plotted in a curve giving the resolution as the ordinate and the distance from the center as the absissa (Figure 6). Minimum v-isible contrast shall be measured w i t h a test phantom as indicated b
32、y Figure 7 and Appendix 2. The measurement ishall be made as fol lows: (a) Radiation measuring Set-up (see Figure 8). (b) Radiation values are 80 KVP and the current adjusted to obtain (c) Contrast measuring Set-up (see Figure 9). (d) Contrast shall be measured by observation with a suitable optical
33、 means in the center of the useful area a t each of 1, 10 and 100 mR/min. at the entrance plane of the tube. Copyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:3
34、1:01 MDTNo reproduction or networking permitted without license from IHS -,-,- EIA TEPLOS 81 m 3234600 0007447 O m above mentioned exposure rates with the remainder of the photo cathode shielded by lead from the unattenuated X-rays. 4.0 Conversion Factor - The conversion factor shall be measured b y
35、 obtaining the quotient of the brightness of the output screen in Foot lamberts (or candelas/m2) b y the input X-ray exposure rate of 100 mR/min of specified quality (half value layer). The X-ray input exposure rate shall be measured as follows: Radiation measuring set-up (see Figure 10). 4 . 1 4.1.
36、1 4.1 2 X-ray qual i ty. The conversion factor shall be measured with X-rays having first half value layers of 5, 7, 9, 11 and 13 mm aluminum. reproducibility the following procedure shall be followed: (a) X-ray generators-single-phase, full wave. (b) Distance from the exposure-meter sensor of the X
37、-ray tube focal spot to the exposure-meter should be 7 1 cm (28 inches). (c) Filters - commercially pure aluminum. (d) Distance from filter t o exposure meter sensor and entrance For maximum plane of Image Intensifier 20 cm (8 inches) minimum. This is important for the elimination of scatter X-ray g
38、enera- ted in the aluminum filter). (Note: (e) ni tiai Settings Approx, Milliamperes First Half Approximate for 100 mill i Value Layer Fi 1 ter KV P Roentgens/Mi nute 5 mm Al. 9 mm Al. 60 1 - 2 80 1 - 2 7 mm Al. 9 mm Al. 11 mm Al. 13 mm Al. 59 mm Al. 140 1 - 2 Note: 20 mm A l . 32 mm A l . 1 O 0 1 -
39、 2 45 mm A l . 120 1 - 2 To arriveat the proper half value layer, it is recommended that corrections can be made in kilovolts peak. - 5 - Copyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie No
40、t for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- EIA TEPLOS A L m 3234600 0007448 2 m 4.1.3 The X-ray beam shall be collimated to expose only the entire useful area. The brightness of the output screen shall be measured over 90% of the diame
41、ter of the useful area with an eye-corrected optical sensor (see Figure 11). An example of a suitable lightmeter is the Spectra brightness spot meter made b y Photo Research Corp. O 4.2 4.2.1 Hollywood, California, Model #U B 1-1/2. - 6 - Copyright Electronic Components, Assemblies & Materials Assoc
42、iation Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- E I A TEPLOS 81 W 3234600 0007449 4 W O .X-ray tube Useful field diameter Useful field diam
43、eter = FIGURE 1 - USEFUL AREA AND FIFLD DIAMETER I X-ray tube X-ray tube Input Lntrance plane plane Y6 cm (14 i -71 cm (28 i n . - d FIGURE 2 USEFUL AREA (CALCULAEED) -7- Copyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees
44、/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- E I A TEPLOS B L 3234600 0007450 O 15.9 mm (0.625 in) P O O O O O 23.8 mrn - ( 0 . 9 3 7 “ ) -. - - m - u Ill Ill Ill IIi Ill Ill 111 A O . o o 0 . 0 e O . O o
45、. O a e e o o e 0 . 0 0 . 0 *e. -u_- FIGURE 3 X-RAY TEST RESOLUTION CHART Naterial - Copper 0.254mm (0.Ol1) . (Darkened areas are openings i n oopper sheet) Copyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, U
46、ser=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo reproduction or networking permitted without license from IHS -,-,- E I A TEPLOS BL 3234600 0807453 2 X-ray. tube 1. _ _ . -/ X-ray tube . . 71 cm (28 i n . ) - J F 1 G W - L RADIATION MEASUREMENT SET-UP .1 Entrance plane Resolution t e s t
47、phantom (See Figure 3 ) O 71 cm (28 in.) FIGURE 5 - - - RESOLVING POWER MEASUREmNT SET-UP I -9- Copyright Electronic Components, Assemblies & Materials Association Provided by IHS under license with ECA Licensee=IHS Employees/1111111001, User=Wing, Bernie Not for Resale, 03/30/2007 00:31:01 MDTNo re
48、production or networking permitted without license from IHS -,-,- E I A TPLOS B L 3234600 0007452 4 111 O 2.5/1.0 5.1/2,0 7.6/3. O 10.2/4.0 12.7/5 .O cm/ inches (From center of input screen) FIGURE 6 RESOLVING POWER TEST PLOT . -lo-. f- Copyright Electronic Components, Assemblies & Materials Association