Forensic Engineering Analysis of Video Screens for a Dispute Over Requirements and Specifications

Robert Peruzzi

doi:10.51501/jotnafe.v38i1.107

Authors

Robert Peruzzi, PhD, PE R. Peruzzi Consulting, Inc. https://orcid.org/0000-0002-4642-9270

DOI:

https://doi.org/10.51501/jotnafe.v38i1.107

Keywords:

forensic engineering, thin film transistor, TFT LCD, video screen, medical electronics, medical electronic equipment, product requirements, product specifications, video quality, video viewing angle, thin film transistor liquid crystal diode

Abstract

This case was about LCD video screens intended to become components of medical equipment requiring an ultra-wide viewing angle. The seller was a wholesaler of various types of video screens from multiple manufacturers. The buyer was a distributor of multiple electrical components for various industries. The OEM, not involved in the case, was a manufacturer of medical instruments and equipment. Claiming that multiple units did not meet the requirements specified in the purchase agreement, the OEM refused a shipment of 1,000 LCD video screens. The buyer had already paid the seller, who refused to take back the shipment and issue a refund or credit. As a result, the buyer sued seller, and the author investigated and submitted expert opinions regarding the following questions: Did performance differ between examined samples? Did each sample meet data sheet specification for viewing angle? And was each sample adequate for its intended application as advertised in the datasheet (that is, for industrial settings requiring ultra-wide viewing angle)?

References

A. J. De Vaan, “Competing display technologies for the best image performance,” Journal of the Society for Information Display, vol. 15, no. 9, pp. 274-279, 2012.

Y. Takakazu and M. Tomoo, “Industrial LCD Display Modules,” NEC TECHNICAL JOURNAL, vol. 2, no. 3, pp. 71 - 74, March 2007.

Wikimedia Commons contributors, “TN display closeup 300X,” Wikimedia Commons, the free media repository., 5 April 2015. [Online]. Available: https://commons.wikimedia.org/w/index.php?title=File:TN_display_closeup_300X.jpg&oldid=155983749. [Accessed 19 June 2018].

Wikimedia Commons contributors, “Color TFT-LCD Layout,” Wikimedia Commons, the free media repository., 9 July 2016 . [Online]. Available: https://commons.wikimedia.org/w/index.php?title=File:Color_TFT-LCD_Layout.png&oldid=201136945. [Accessed 19 June 2018].

Wikimedia Commons contributors, “Color TFT-LCD Cells-Schematic,” Wikimedia Commons, the free media repository., 21 October 2016 . [Online]. Available: https://commons.wikimedia.org/w/index.php?title=File:Color_TFT-LCD_Cells-Schematic.png&oldid=210429248. [Accessed 20 June 2018].

J. Stohr and M. G. Samant, “Liquid crystal alignment by rubbed polymer surfaces: a microscopic bond orientation model,” Journal of Electron Spectroscopy and Related Phenomena, Vols. 98-99, p. 189–207, 1999.

NEC LCD Technologies, Ltd., Data Sheet: TFT Color LCD Module, NEC LCD Technologies, Ltd., 2007.

EIZO Corporation, “The difference in image quality is perfectly obvious! - Let's check the LCD's display,” EIZO Corporation, 2018. [Online]. Available: http://www.eizoglobal.com/library/basics/difference_in_image_quality/index.html. [Accessed 22 June 2018].

International Committee for Display Metrology (ICDM), “https://vesa.org/vesa-standards/,” Society for Information Display, 1 June 2012. [Online]. Available: https://vesa.org/vesa-standards/. [Accessed 22 June 2018].

R. Barczyk, B. Kabzinski, D. Jasinska-Choromanska and A. Stienss, “Measuring of the Basic Parameters of LCD Displays,” Journal of Automation, Mobile Robotics & Intelligent Systems, vol. 6, no. 1, pp. 46-48, 2012.

E. Lee, J. H. Chong, S. A. Yang, H. J. Lee, M. Shin, S. Y. Kim, D. W. Choi, S. B. Lee, H. Y. Lee and B. H. Berkeley, “Improved Angle-of-View Measurement Method for Display Devices,” Journal of Information Display, vol. 11, no. 1, pp. 17 - 20, 2010.

R. M. Luo and C. Li, “CIECAM02 and Its Recent Developments,” in Advanced Color Image Processing and Analysis, New York, Springer, 2013, pp. 19 - 58.

R. Soneira, “16 Misleading Display Specs and What They Really Mean,” GIZMODO, 20 August 2012. [Online]. Available: https://gizmodo.com/5936192/[object%20Object]. [Accessed 22 June 2018].

S. Fallon, “New LCD Display From NEC Can Switch Between Wide and Narrow Viewing Angles,” Gizmodo, 7 October 2007. [Online]. Available: https://gizmodo.com/314799/[object%20Object]. [Accessed 25 June 2018].

NEC LCD Technologies, Ltd., “TFT Color LCD Module NL6448BC33-53 Data Sheet,” January 2007. [Online]. Available: http://www.farnell.com/datasheets/68814.pdf. [Accessed 25 June 2018].

NEC LCD Technologies, Ltd., “TFT Color LCD Module NL6448BC33-54 Data Sheet,” March 2003. [Online]. Available: http://www.beyondinfinite.com/lcd/Library/Nec/NL6448BC33-54.pdf. [Accessed 25 June 2018].

LCD Parts, “LST03-V3 LCD Screen Tester,” LCD Parts, 2013. [Online]. Available: http://www.lcdparts.net/LST03.aspx. [Accessed 25 June 2018].

LCD Parts, “LCD Screen Wire Harness,” LCD Parts, 2013. [Online]. Available: http://www.lcdparts.net/WHSDetail.aspx?ProductID=3949. [Accessed 25 June 2018].