Apeldyn Corp. v. AU Optronics Corp.

831 F. Supp. 2d 817, 2011 U.S. Dist. LEXIS 134759, 2011 WL 5552520
CourtDistrict Court, D. Delaware
DecidedNovember 15, 2011
DocketCiv. No. 08-568-SLR
StatusPublished
Cited by1 cases

This text of 831 F. Supp. 2d 817 (Apeldyn Corp. v. AU Optronics Corp.) is published on Counsel Stack Legal Research, covering District Court, D. Delaware primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Apeldyn Corp. v. AU Optronics Corp., 831 F. Supp. 2d 817, 2011 U.S. Dist. LEXIS 134759, 2011 WL 5552520 (D. Del. 2011).

Opinion

MEMORANDUM OPINION

SUE L. ROBINSON, District Judge.

I. INTRODUCTION

Plaintiff Apeldyn Corporation (“plaintiff’ or “Apeldyn”) filed the complaint in this action on September 8, 2008 against, inter alia, defendants AU Optronics Corporation and AU Optronics Corporation America (collectively, “AUO”) and Chi Mei Optoelectronics Corporation and Chi Mei Optoelectronics USA, Inc. (collectively, “CMO”). (D.I. 1) Therein, plaintiff alleged infringement of its U.S. Patent No. 5,347,-382 (“the '382 patent”), which is directed to the response time of liquid crystal material in VA mode Liquid Crystal Display modules (“LCDs”). Currently pending before the court are: (1) AUO’s motion for summary judgment of invalidity (D.I. 503); (2) AUO’s motion for summary judgment of noninfringement (D.I. 504); (3) CMO’s motion for summary judgment of no inducement of patent infringement (D.I. 505); and (4) CMO’s motion for summary judgment of noninfringement (D.I. 508). Trial is scheduled to commence on December 5, 2011.

II. BACKGROUND

A. Technology Overview1

The applications for LCDs are well-known and include computer monitors, televisions, cell phones, and other digital displays. LCDs are composed of pixels containing a layer of liquid crystal molecules between two polarizing filters (also called polarizers). The polarizers contain (or are adjacent to) electrodes so that voltage can be applied to the cell. The two polarizers typically are arranged such that the axes of transmission are perpendicular to each other. A polarizer can be analogized to a picket fence — it will screen out light except where there is an opening for it to pass through. Per the analogy, the slots in the fence do not align, and light cannot pass all of the way through unless it is altered within the cell.

LCDs do not produce light; they require an external light source. LCDs use the light modulating properties of liquid crystals to emit light. Light entering the cell is unpolarized, which means that light waves are moving simultaneously in many directions in space. Unpolarized light then passes through the cell’s first polarizer. The slice of light’s electromagnetic spectrum that is allowed to pass into the cell is called polarized light.

Polarized light can be thought of as the sum of two components, which are orthogonal (intersecting) and at 90 degree angles to each other. Polarized light entering the [821]*821cell does so “in phase,” meaning that the two components are lined up precisely to each other. Applying a voltage to the cell causes the liquid crystals to move, bringing the two components of light out of phase. The degree to which the components are brought out of phase with each other is called the “retardance.” One phase will remain unchanged (the “fast phase”), while the other will be delayed in effect (the “slow phase”). The amount of delay will determine how much light exits the cell.

There are several different types of liquid crystal cells. A schematic of a twisted nematic mode cell (or “TN” mode cell) appears below.

[[Image here]]

A TN cell is also referred to as an “optical rotator” because the polarized light is turned or rotated in the liquid crystal material. The light is not brought out of phase and, therefore, there is no retardance occurring. In the power-off state, the liquid crystal molecules are oriented in a helical configuration (a 90 degree twist) between the two plates. Polarized light may pass through the first polarizer, become rotated by the helical structure of the liquid crystal material, and pass through the light output polarizer. In the power-on state, the polarized light entering the liquid crystal material from the first polarizer will not be rotated, and it is blocked by the light output polarizer on the other side of the cell, which is set at 90 degrees from (or perpendicular to) the first polarizer.

Another type of cell is referred to as a vertical alignment mode cell (“VA” or “eigen-axis” mode cell), as depicted below.

[822]*822[[Image here]]

In contrast to the TN cell, the VA mode cell is dark in the power-off state. The liquid crystal material in the VA system is naturally horizontal. Absent an applied voltage, the liquid crystals remain perpendicular to the polarizers; polarized light enters the cell but is blocked by the light output polarizer on the top of the cell. As the blockage is complete, VA cells produce a high-quality black image. When a voltage is applied, the molecules of the liquid crystal material will uniformly shift to a tilted position allowing light to pass through the light output polarizer. The light output varies by the amount of tilt (towards horizontal, for a bright white image) generated by the electric charge.

“Eigen-axes” are indices of refraction along which polarized light travels through a liquid crystal cell. The eigen-axes are orthogonal to each other (they are intersecting). The eigen-axis along which light travels faster is known as the fast axis, the eigen-axis along which light travels slower is known as the slow axis. Polarized light traveling along either eigen-axis will remain linearly polarized and will exit the liquid crystal cell along the same eigenaxis. VA cells may be referred to as “eigen-axis” mode cells (as per the illustration above) where polarized light exits the cell along the same eigen-axes upon which the components traveled through the cell.2

B. The'382 Patent

The '382 patent, entitled “Liquid crystal cell retarder with driving beyond retardance value and two cells for high speed,” was filed April 23, 1992 and issued September 13, 1994; Scott H. Rumbaugh is the sole inventor. The specification provides that liquid crystal cell retarder systems known at the time of filing and “used to vary polarization by switching between intermediate values over a range of retardances” suffered from “two significant drawbacks.” ('382 patent, col. 1:45-48)

First, a change in retardance in one direction must be effectuated by the application of an increased ac voltage, but the response speed of the retarder in [823]*823that direction is limited by the responsiveness of the liquid crystal cell material. Second, a change in retardance in the other direction must be effectuated by reducing the applied voltage and allowing the liquid crystal material to relax back to a new retardance; that is, it cannot be driven by the application of a voltage. These two drawbacks greatly limit the response speed of a liquid crystal cell retarder and, therefore, the applications to which the retarder may be put. In particular, the slow response time of known liquid crystal cell retarder systems limits the speed with which they can switch between intermediate values, and corresponding polarization states, over a wide range of retardances.

(Id., col. 1:49-65) The disclosed invention purports to solve these needs with “impulse switching,” or “the application of a voltage in excess of the voltage corresponding to the target retardance,” and through the use of stacked, “opposing” retarders. (Id., col. 2:6-10, 2:24-27)

Increasing the applied voltage was discovered to increase the rate at which a liquid crystal cell retarder switches from one resistance to another resistance under the influence of an electric field. (Id., col.

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Bluebook (online)
831 F. Supp. 2d 817, 2011 U.S. Dist. LEXIS 134759, 2011 WL 5552520, Counsel Stack Legal Research, https://law.counselstack.com/opinion/apeldyn-corp-v-au-optronics-corp-ded-2011.