1、EIA TEPLOS-12 87 W 3234600 O007326 T = 7 . .%- e c I In 0 i w I- - TEPAC P U B L I CAT ION Test Method for Tube Face Reflectivity APRIL 1987 ELECTRONIC INDUSTRIES ASSOCIATION ENGINEERING DEPARTMENT I % w EIA TEPL05-LZ 87 m 3234b00 0007327 L NOTICE EIA Engineering Standards and Publications are desig
2、ned 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 particular need. Existence of
3、 such Standards and Pub- lications 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 such Standards and Publications preclude their voluntary use by those other than E
4、IA 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 liability
5、 to any patent owner, nor does it assume any obligation whatever to parties adopting the Recom- mended Standard or Publication. Published by ELECTRONIC INDUSTRIES ASSOCIATION Engineering Department 2001 Eye Street, N.W. Washington, D.C. 20006 PRICE: $5.00 Published in U.S.A. EIA TEPLOS-12 87 m 3234b
6、00 0007328 3 m TEP10 5 - 12 TEST METHOD FOR TUBE FACE REFLECIIVITY - This publication was formulated under the cognizance of the JT-31 Committee on Optical Characteristics of Display Devices and approved by the Tube Engineering Panel Advisory Council (TEPAC) The TEP105 series of publications compris
7、es a set of test methods developed for industrial cathode ray tubes. cathode ray tubes with respect to parameters, which are of interest to users of these devices e They are intended to be useful in evaluating i EIA TEPLO5-L2 7 3234600 0007329 5 TEP 105 - 1 2 Page 1 254mn (10.0 in TEST METHOD FOR TU
8、BE FACE REFLECTIVITY Tube face reflectivity is measured as follows: a 304.8m (12.0 in.) 152.4mm(6 in.) r-1 an -a 1 Aperture Aperture Photo - - Circle (- -,- 76.2m (3.0 in.) 101.6mm (4.0 in.) L aBp +- F* /* The schematic arrangement of the box is shown in the sketch above. NOTES: - 1. The dimensions
9、of the box are 254m (10 in.) x 254m (10 in.) x 294.8mm (12 in.) . Use 1.6m (0.06 in.) aluminum sheet metal. 2. The photocell defined acceptance angle (a) subtends a 76.2m (3.0 in.) diameter circle at the entrance port. a 727mm (5.0 in.) diameter circle to safeguard against incorrect readings, Howeve
10、r, the entrance port is EIA TEP105-12 87 W 3234b00 0007330 1 c TEP10 5 - 12 Page 2 TUBE FACE REFLECTIVITY (contd.) Equipment: 1. (a) Flat black painted (suggested source 1.Gmm 1/16 in. aluminum sheet) sheet metal box. Photocell with suitable filter so that its response closely matches the standard o
11、bserver Y function under illuminant C as per CIE (1931). “Warm-White“ fluorescent circular lamp, 203mm (8.0 in.) diameter with ballast box, on-off switch and power cord. (b) (c) I 2. Variable gain micro-ammeter or an operational amplifier circuit and 3-1/2 digit, digital voltmeter. 3. 4“ x 4“ Vitrol
12、ite Tile (7.8 J Vitrolite white glass standard of diffuse reflectance 400 - 750 nm) sbggested source - N.B.S., Washington, O. C. 20234 TEST PROCEDURE- 1. Plug into AC line; connect microammeter. Lamp turned off. 2. Set meter at zero with box facing.black velvet cloth, excluding all ambient light. Tu
13、rn on lamp, allow three minutes warmup, and set meter reading to 100.0 with box placed against standard surface (vitrolite tile with approximately 88% reflectivity). 3. Check zero with black velvet cloth with lamp on. 4. Hold box against surface to be measured and record meter reading. face reflecti
14、vity is given by ratio of sample to standard surface reading times the absolute reflectivity of the standard (approximately .88). That is.sample reading Tube x .88 = Tube Face Reflectivity standard reading 5. The light port should be held at a distance from the standard corresponding to the distance
15、 from the phosphor screen and the tube face. 6, The linearity of the unit should be checked, of checking the system linearity is to place the box over the Vitrolite standard as in 3 and remove the side panel and insert suitable 2“ x 2“ neutral density filters over the 1-1/3 inch aperture. After fabrication, one method
