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Murphy B.T.,University of Texas at Austin | Hebner R.E.,University of Texas at Austin | Kelley E.F.,KELTEK LLC
IEEE Transactions on Dielectrics and Electrical Insulation | Year: 2011

The primary new information from this investigation is the simulation of a transition from one streamer mode to another during propagation. The transition is characteristic of experimental data, but has not heretofore been described in a model. This demonstrates that the conceptual framework describing prebreakdown streamers in liquids as stochastic growth of a branching fractal tree in point-plane geometry is capable of simulating a wide range of streamer propagation behaviors in insulating liquids. The work also improved the approach in the model for scaling the potential at nearby grid points and explored some of the influences of computational choices, specifically needle length and grid size, on the predicted results. © 2006 IEEE.


Penczek J.,University of Colorado at Boulder | Penczek J.,U.S. National Institute of Standards and Technology | Kelley E.F.,KELTEK LLC | Boynton P.A.,U.S. National Institute of Standards and Technology
Digest of Technical Papers - SID International Symposium | Year: 2015

A set of optical transmission measurements are put forth which can be used to determine the optical performance of transparent displays under arbitrary ambient lighting environments. The methodology measures the transmission coefficients in order to determine the on-screen photometric and colorimetric characteristics of transmissive, emissive, and reflective displays. An LCD transparent display is used as an example to demonstrate these methods. © 2015 SID.


Penczek J.,University of Colorado at Boulder | Penczek J.,U.S. National Institute of Standards and Technology | Kelley E.F.,KELTEK LLC | Boynton P.A.,U.S. National Institute of Standards and Technology
Digest of Technical Papers - SID International Symposium | Year: 2015

A framework is described which allows a generalized treatment of display ambient characteristics. The proposed methodology incorporates both display reflection and transmission properties. An LCD and OLED transparent display are used as an example to demonstrate the utility of this framework. © 2015 SID.


Kelley E.F.,KELTEK LLC
Digest of Technical Papers - SID International Symposium | Year: 2011

The International Committee for Display Metrology of the Society for Information Display is releasing the Information Display Measurements Standard (IDMS) to assist industry in dealing with display metrology issues. We review the history of the document, its philosophy, its structure, and new content. © 2011 SID.


Kelley E.F.,Keltek LLC
Information Display | Year: 2013

One of the creators of the IDMS (Information Display Measurements Standard) takes the measure of the very latest large, curved OLED TVs. In this first article in a series, he looks at color performance. © SID 2013.


Kelley E.F.,KELTEK LLC
Proceedings of International Meeting on Information Display | Year: 2010

The new measurement standard document from the International Committee for Display Metrology (ICDM) sponsored by the Society for Information Display (SID) is a considerable expansion of the FPDM2 document from VESA (Video Electronics Standards Association). Major new chapters are 3D-stereo, motion, gray and color scales, and projection metrics. Concerns for reasonable contrast metrics and more than three primaries are discussed. We review the philosophy, the structure, content, and possible future directions of the ICDM effort.


Kelley E.F.,KELTEK LLC
Information Display | Year: 2011

There are presently two main competing commercial liquid-crystal-display (LCD) stereoscopic technologies for home television that requires the use of glasses: temporally multiplexed (TM) displays that use active glasses and spatially multiplexed displays that are often called patterned-retarder (PR) displays that use passive glasses. The active glasses are synchronized with the left-eye/right-eye sequence as each eye's information is displayed in TM display. In the PR displays, each horizontal line has the opposite circular polarization, and the passive glasses have a left-circular polarized filter for the left eye and a right- circular polarized filter for the right eye. In attempting a comparison of different technologies, it is important to remember that display settings can affect measured and perceived resolution. Differences in the appearance of images rendered by the PR and TM displays such as the presence of larger black gaps between the horizontal lines of the PR display may be attributed to differences in the pixel layouts between the displays that result in different fill factors.


Kelley E.F.,KELTEK LLC
49th Annual SID Symposium, Seminar, and Exhibition 2011, Display Week 2011 | Year: 2011

The International Committee for Display Metrology of the Society for Information Display is releasing the Information Display Measurements Standard (IDMS) to assist industry in dealing with display metrology issues. We review the history of the document, its philosophy, its structure, and new content.


Kelley E.F.,Keltek LLC
Information Display | Year: 2014

The article examines reflection performance and makes a discovery that may necessitate a revision to the reflection measurement procedure in the IDMS standard. One of the best ways to visually inspect the reflection properties of any display is to use a point source. To capture that same dynamic range with photography requires multiple images of varying exposures. The LG display is apparently employing an anti-reflection front surface (a magenta hue), and the Samsung display exhibits a very wide matrix-scatter distribution. Neither display has a strong diffusing front surface, so there is essentially no haze component of reflection. The Samsung OLED distributes more of the energy in a wide-angle pattern because of the wide matrix scatter. This results in less energy in the specular direction, whereas the LG OLED display exhibits less matrix scatter and more of the energy remains in the specular direction with less scattered out of the specular direction.


Kelley E.F.,KELTEK LLC
Digest of Technical Papers - SID International Symposium | Year: 2013

We consider the employment of high-quality consumer cameras in the photography of display surfaces. We examine the conversion to tristimulus images and the linearity of the camera and display. Three magnification regimes are of interest: subpixel details, pixel details without subpixel resolution, and full-screen photography without aliasing. © 2013 Society for Information Display.

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