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Minutes of JT-31 Optical Characteristics
September 26, 2002
NIST Bldg. 225, Gaithersburg, MD

1.0 Committee organization and procedures

1.1 Membership and attendance

1.1 Welcome by George Ehemann and self- introduction of attendees. It was determined that a quorum was present. The group felt that Philips and Toshiba should be participants in the work of this committee. Mr. Rowe also mentioned that the IEC PDP (Plasma Display Panels) is meeting tomorrow. He will see if there is any interest in members there participating in JT-31.

1.2 Approval of JT-31 Minutes 22 May 2002 meeting in Boston, MA
Minutes from meeting of 22 May 2002 held in Boston, MA were modified to replace "bivariant" with "bidirectional" in Section 3.1 Para. 2. Also to change '300MM' to '300mm' in the same paragraph. The minutes were subsequently unanimously approved.

1.3 Correspondences
Correspondence was received from Bill Rowe. He sent his regrets he would not be able to attend the meeting. He also indicated the Phosphor Registration Template, which is posted on the ECA website in the engineering section for JT-31, has a broken link to the file. He requested that the link be re-established. Ed Mikoski took it as an action item.

2.0 Old Business

2.1 Status of the new electronic template for phosphor registration
The registration system on the ECA website is posted. As mentioned in the correspondence above, the link is broken. That will be repaired and the contact cited in the document will be changed from Bernie Aronson to Ed Mikoski.

Discussion pursued regarding the need in the industry for the registration of flat panel displays for phosphor backlighting and problems related to the diffuser changing spectrum. The group sees the future need to accurately control these items for the anticipated demands for accuracy of image color and clarity for the e-commerce market.

It was determined that there is also a need for standardization relative to measurement equipment. Measurement documents need to be developed.

2.2 TEP-105-15, Glass Aging
Bob Donofrio had recently delivered a paper in the Ukraine. It discussed the shape of the profile of the beam and how one can measure change where one is on the curve. This is especially pertinent to a CRT where there are fill lines. This is not trivial to define. The subject is covered in an article located on his website. It reviews different methods that are used. (http://www.ddc-co.com under publications)

The group also discussed the glass aging summary from several years ago to predict electron browning. The document was delivered to JT-31 as Report #L4762 PRE from Corning entitled, Quantitative Model for Prediction of Electron Browning from CTV Panel Composition of 9/10/98 David Tammaro.

2.3 TEP-105-12 Test Method for Tube Face Reflectance
TEP-105-12 is the existing document. The technology has evolved from 12x12x10 to 6 inches deep so the document needs to be revisited. There should perhaps be a new sketch introduced to the document. After an extensive discussion about correlation between methods, Ed Kelley delivered a presentation on the Specular, Lambertian, and haze components in the in plane BRDF (bidirectional reflectance distribution function) for CRTs and Flat Panels and the problems associated with it. So far, there are four measurements that are fairly robust. (This method is not designed for an orange-peel surface.) 1) Diffuse illumination method, 2) Large Source Specular Direction Method, 3) Ring Light Method, 4) Small Source Specular (no robustness to this but a super small variable radius source would work well.

The group also discussed the concept of Modulation Transfer Function (MTF) method.

The concept of using a knife edge or step response transition was also briefly addressed.

3.0 New Business

3.1 Phosphor Catalog TEPAC 116-C to searchable CD
Kevin Brady of NIST will look into this document as to how feasible it is to scan and plot graphical points for converting the paper-based curves to electronic data.

3.2 IEC 441 update
George Ehemann will discuss this document with Bill Rowe. It was felt that we should re-establish contact with the Georgia Tech Phosphor Institute. Specifically, a Dr. Brent Wagner and Dr. Chris Summers. The group also deduced that Sandia Labs is working on Phosphors. George Ehemann agreed to re-establish contact with all these individuals.

3.3 Tour of NIST Metrology
The group visited the NIST labs in the afternoon to visually witness the effectiveness of various optical measurements. The committee expressed its appreciation for this opportunity.

4.0 Future Business Meetings

4.1 The group asked that the Chair look into the feasibility of holding the next meeting during the upcoming SID conference in Baltimore in May or June.
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5.0 Meeting adjourned at approximately 4:00pm.

This meeting was conducted in accordance with the EIA Legal Guidelines and the Manual of Organization and Procedures.

George Ehemann , Chairperson

Ed Mikoski , Secretary

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