ECA 527-1986 Screen Definition for Color Picture Tubes.pdf

1、r a EIA 527 86 m 3234600 0073747 L m - =- 1- ANSI/EIA-527-1986 APPROVED: JUNE 16, 1986 b OJ in I W a - m O EIA STANDARD SCREEN DEFINITION FOR COLOR PICTURE TUBES EIA-527 JUNE 1986 Engineering Department ELECTRQWC INDUSTRIES ASSOCIATION EIA 527 8b m 3234600 0073748 3 NOTICE EIA Engineering Standards

2、and Publications are designed to serve the public interest through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his par

3、ticular need. Existence of such Standards and Pub- lications shall not in any respect preclude any member or non-member of ?IA from manufacturing or selling products not conforming to such Standards and Publications, nor shall the existence of such Ctandards and Publications preclude their voluntary

4、 use by those other than 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 doe

5、s not assume any liability to any patent owner, nor does it assume any obligation whatever to parties adopting the Recom- mended Standard or Publication. This EIA Recommended Standard is considered to have international stm- dardization implications, but the IEC activity has not progressed to the po

6、int where a valid comparison between the EIA Recommended Standard and the IEC Recommendation can be made. Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineer i ng De part ment 2001 Eye Street, N.W. Washington, D.C. 20006 Copyright 1986 Al1 rights reserved ELECTRONIC INDUSTRIES ASSOCIATION PRICE:

7、 $5.00 Published in U.S.A. O e e - EIA 527 b m 3234600 0073749 5 m EIA-527 FOREWORD This Recommended Standard supersedes Recommended Standard EIA-324-A, “Registered Screen Dimensions for Color Picture Tubes,“ for all new panel designs intended for use in shadow-mask type color TV picture tubes and c

8、olor monitor tubes as defined in the Worldwide Type Designation System - EIA Publication TEP-106-A. The reason for this new Standard is as follows: The previous Standard EIA-324-A places the printed screen 30O into the heel radius of the panel. The deviation between the inside faceplate contour and

9、the heel radius results in significant iiq“ errors at the edge of the screen. With flatter panels the refractive gain is less. This reduction in refractive gain would require the tube manufacturers to print larger screens extending farther into the heel radius area (thus increasing the “q“ error) in

10、 order to meet the minimum published screen established by EIA-324-A. i f- o O a O - IA 527 8b = 3234600 0073750 L EIA-527 Page 1 SC REEN DEF I NIT ION FOR COLOR PICTURE TUBES (From Standards Proposal No. 183, formulated under the cognizance of the EIA JT-6 Committee on Tricolor Cathode-Ray Tubes.)

11、1.0 SCOPE This Recommended Standard defines the method for establishing the relationship between the inside face panel edge geometry and the minimum published screen dimensions for shadow-mask color TV picture tubes and color monitor tubes (as defined in the Worldwide Type Designation System - EIA P

12、ublication TEP- 106-A). It may also be used to determine the minimum published screen dimensions for an established panel design. Use of this Standard will establish the standard minimum published screen dimensions. If a tube manufacturer desires a smaller screen size than the standard for a particu

13、lar tube, it must be specified in the registered data for that type. The method takes into account the refractive gain through the glass panel and provides a specific tolerance to allow for manufacturing variations. The object is to have the screen area lie entirely within the main inside faceplate

14、contour of the panel. This will avoid “q“ errors resulting from printing the screen into the heel radius. 2.0 PROCEDURE FOR ESTABLISHING A NEW PANEL DESIGN 2.1 The procedure for establishing a new panel design for given screen dimensions is as follows: (Refer to Fj.gure 1). 2.2 Establish the approxi

15、mate glass panel design. 2.3 Calculate the refractive gain of the glass panel at various points on the screen periphery. Usually the points at each end of the diagonals and the major and minor axes are sufficient. Subtract these values from the desired minimum published screen values to give the act

16、ual minimum screen on the inside surface of the panel. EIA 527 b m 3234600 a073751 3 EIA-527 Page 2 2.4 The minimum dimension from the tube axis to the point of tangency between the main faceplate contour and the heel or blend. radius should lie beyond the actual minimum screen (as determined in Ste

17、p 2) by a Safety Factor of 1.0 mm. If the initial panel design cannot meet this condition, the panel design should be modified by an adjustment in the position and/or the magnitude of the heel radius. In those cases where the panel design cannot be modified, the panel drawing should still show the m

18、inimum published screen dimensions. In addition, the “q“ errors (parallel to the central tube axis) resulting from the deviation from the standard method should be shown. It is recommended that these cases be discussed by EIA Committee JT-6 if the tube and glass companies cannot come to an agreement

19、. 2.5 For types employing a completely rectilinear minimum published screen (perfectly straight sides and square corners), the dimensions shall be established as follows: the diagonal will be established as above, the major and minor axes dimensions will be ratios of the diagonal dimension. Example:

20、 for a 3 x 4 aspect ratio, the major axis dimension would be 4/5 of the diagonal dimension and the minor axis dimension would be 3/5 of the diagonal dimension. Using this method will result in a greater safety factor between the inside minimum screen and the tangency point between the main faceplate

21、 contour and the heel radius all around the screen periphery except on the diagonals. 2.6 For use of this Standard to determine the minimum published screen dimensions on an established panel design having an undefined screen, the starting point is the minimum dimensions to the points of tangency be

22、tween the faceplate contour and the heel radius. The safety factor and refractive gain are handled in the reverse order as described above to derive the minimum published screen dimensions. In all cases, the registered panel drawings shall specify the minimum published screen dimensions and area. Th

23、e screen area is the projected area enclosed by the minimum published screen dimensions. The panel drawings should also show the calculated refractive gain and the dimensions to the minimum points of tangency between the main faceplate contour and the heel radius at the ends of the diagonals and the

24、 major and minor axes. EIA 527 Ab m 3234b00 0073752 5 m - EIA- 527 Page 3 O MINIMUM PUBLISHED SCREEN DIMENSION I REFRACTIVE I 4 MINIMUM DIMENSION BETWEEN HEEL RADII CENTERS e MINIMUM DIMENSION TO POINT OF TANGENCY 1.0 um SAFETY FACTOR ,- R = Main Inside Faceplate Contour r = Heel or Blend Radius Q FIGURE 1 SECTIONAL VIEW OF COLOR PICTURE TUBE FACE PANEL ILLUSTRATING THE ESTABLISHMENT OF SCREEN DIMENSIONS I o