DCT
2:17-cv-00729
Lemaire Illumination Tech LLC v. Microsoft Corp
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Lemaire Illumination Technologies, LLC (Texas)
- Defendant: Microsoft Corporation (Washington); Microsoft Mobile Inc. (Delaware); and, Microsoft Mobile Oy (Finland)
- Plaintiff’s Counsel: Strasburger & Price, LLP; Ni, Wang and Massand, PLLC
- Case Identification: 2:17-cv-00729, E.D. Tex., 11/07/2017
- Venue Allegations: Venue is based on allegations that Defendants maintain a regular and established physical place of business in the district and have committed acts of infringement there. For Defendant Microsoft Mobile Oy, a foreign corporation, venue is asserted under 28 U.S.C. § 1391(c)(3).
- Core Dispute: Plaintiff alleges that Defendants’ Microsoft Lumia smartphone product line infringes three patents related to controlling pulsed LED camera flashes to achieve consistent brightness and accurate color.
- Technical Context: The technology addresses methods for driving multi-color LED arrays in battery-powered devices to compensate for voltage drop and adjust the light's color spectrum, a crucial capability for modern smartphone camera flashes.
- Key Procedural History: The asserted patents all claim priority to a 1998 application. Post-issuance, U.S. Patent No. 6,095,661 survived two inter partes review (IPR) proceedings, though numerous non-asserted claims were cancelled. The asserted claim of U.S. Patent No. 6,488,390 was disclaimed by the patent owner in 2019, after this complaint was filed, raising a significant question about the continued viability of that infringement count.
Case Timeline
| Date | Event |
|---|---|
| 1998-03-19 | Priority Date for ’661, ’390, and ’266 Patents |
| 2000-08-01 | ’661 Patent Issued |
| 2002-12-03 | ’390 Patent Issued |
| 2015-08-25 | ’266 Patent Issued |
| 2015-10-06 | Accused Lumia Devices Unveiled |
| 2015-11-20 | Accused Lumia Devices First Offered for Sale in the U.S. |
| 2017-11-07 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,095,661 - Method and Apparatus for an L.E.D. Flashlight
Issued August 1, 2000
The Invention Explained
- Problem Addressed: The patent addresses the problem that battery-powered light sources, including those using LEDs, tend to dim as the battery's voltage decreases during use, leading to inconsistent light output (Compl. ¶20; ’661 Patent, col. 1:22-29). Additionally, simple resistor-based circuits for driving LEDs are inefficient, wasting power as heat (’661 Patent, col. 1:31-35).
- The Patented Solution: The invention proposes an electrical control circuit that drives LEDs with pulsed power. This circuit is designed to solve the problem by actively managing the pulses to maintain a consistent, predetermined brightness level and control the color spectrum, even as the battery voltage fluctuates (’661 Patent, Abstract; col. 2:25-35). The control can be based on feedback from the battery voltage or the light output itself (’661 Patent, col. 2:30-40).
- Technical Importance: This approach enabled the creation of more efficient, portable LED lighting systems with stable output, a key requirement for applications like camera flashes where consistent illumination is critical for image quality (Compl. ¶21-22).
Key Claims at a Glance
- The complaint asserts independent claim 34 (Compl. ¶58-59).
- The essential elements of claim 34 are:
- An illumination source comprising:
- (a) a light-emitting diode (LED) housing with one or more LEDs; and
- (b) an electrical control circuit that selectively applies pulsed power from a DC voltage source to the LEDs to:
- control a light output color spectrum of the one or more LEDs, and
- maintain a predetermined light output level as the DC voltage source varies.
- The complaint alleges infringement of "one or more claims..., including at least claim 34," potentially reserving the right to assert others (Compl. ¶58).
U.S. Patent No. 6,488,390 - Color-Adjusted Camera Light and Method
Issued December 3, 2002
The Invention Explained
- Problem Addressed: Beyond simple brightness, the patent tackles the challenge of accurately controlling the color of light produced by an LED source, which is particularly important for camera illumination to ensure natural-looking photographs (Compl. ¶21; ’390 Patent, col. 1:13-17).
- The Patented Solution: The invention describes a control circuit that uses two distinct techniques in concert: it "adjusts a height of the [electrical] pulses" (i.e., their amplitude/current) to control the color spectrum, and it separately "adjusts an LED on-time proportion" (i.e., the pulse width or duty cycle) to control the overall brightness or amount of light (’390 Patent, Abstract; col. 12:5-14).
- Technical Importance: This method provided a specific dual-control architecture for independently managing both color and brightness in an advanced LED flash system, facilitating dynamic color correction (Compl. ¶22).
Key Claims at a Glance
- The complaint asserts independent claim 19 (Compl. ¶73-74).
- The essential elements of claim 19 are:
- An illumination source comprising:
- a housing;
- one or more LEDs attached to the housing;
- a control circuit supplying electrical pulses to the LEDs that:
- adjusts a height of the pulses to control a color spectrum; and
- adjusts an LED on-time proportion to control an amount of output light.
- The complaint alleges infringement of "one or more claims..., including at least claim 19" (Compl. ¶73).
U.S. Patent No. 9,119,266 - Pulsed L.E.D. Illumination Apparatus and Method
Issued August 25, 2015
- Technology Synopsis: This patent discloses a method for dynamically correcting the color of a photograph. The method involves using a device's camera to obtain an image signal, measuring the color balance of that signal, and then adjusting the spectrum of the device's multi-color LED flash based on that measurement to achieve a corrected color balance in the final image (Compl. ¶89; ’266 Patent, Abstract).
- Asserted Claims: The complaint asserts independent method claim 9 (Compl. ¶88-89).
- Accused Features: Plaintiff alleges that the Accused Devices perform this method by using their camera and processor to measure the color balance of a scene and then adjusting their "triple LED flash" to complement the ambient lighting conditions (Compl. ¶21, ¶89).
III. The Accused Instrumentality
Product Identification
- The Microsoft Lumia 950 Dual-SIM, Lumia 950 XL, and Lumia 950 Single-SIM smartphone devices (Compl. ¶2).
Functionality and Market Context
- The complaint focuses on the camera flash system of the Accused Devices, which is described as a "triple LED flash" (Compl. ¶39).
- The core accused feature is the phones' "natural three LED (red, green, blue) flash" which, according to Microsoft marketing materials cited in the complaint, "automatically matches the colors of the ambient light" (Compl. ¶40, ¶46, ¶52). For example, the complaint quotes descriptions of the flash producing "a blue light to complement the bluish color of the scene" at twilight or adjusting "to expose candlelight" for a candlelit dinner (Compl. ¶40). This functionality is alleged to be driven by an electrical control circuit that provides pulses from the battery to the LEDs (Compl. ¶40, ¶59, ¶74).
- The complaint also alleges that this control circuit maintains the light output level as the battery's charge varies (Compl. ¶40, ¶59). No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
’661 Patent Infringement Allegations
| Claim Element (from Independent Claim 34) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| An illumination source, comprising: (a) a light-emitting diode (LED) housing comprising one or more LEDs; | The Accused Devices are illumination sources with a "triple LED flash" containing one or more LEDs and a supporting case structure. | ¶59 | col. 18:21-23 |
| and (b) an electrical control circuit that selectively applies pulsed power from a DC voltage source...to the LEDs | The Accused Devices contain an electrical control circuit that provides a "set of pulses" from the battery to the flash. | ¶59 | col. 19:40-46 |
| to control a light output color spectrum of the one or more LEDs | The set of pulses allegedly changes to control the color spectrum of the flash, such as by matching ambient light. | ¶59, ¶40 | col. 20:1-4 |
| and maintain a predetermined light output level of the LED units as a charge on the DC voltage source varies. | The control circuit allegedly "maintains the light output as the DC voltage source (i.e., the battery) charge varies." | ¶59, ¶40 | col. 19:46-51 |
Identified Points of Contention
- Scope Questions: Does the accused function of "match[ing] the colors of the ambient light" meet the claim requirement to "maintain a predetermined light output level"? A central dispute may be whether the primary function of the accused system is color matching, with brightness consistency being an incidental effect, versus the claimed primary function of maintaining a set brightness level.
- Technical Questions: The complaint alleges the accused circuit "maintains the light output" as the battery drains (Compl. ¶59), but the provided marketing materials focus on color matching. The case may turn on whether Plaintiff can produce technical evidence that the devices perform the specific function of brightness stabilization as a "predetermined" and controlled parameter.
’390 Patent Infringement Allegations
| Claim Element (from Independent Claim 19) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| An illumination source comprising: a housing; one or more light-emitting diodes (LEDs) attached to the housing; | The Accused Devices have a supporting case structure and a "triple LED flash" with one or more LEDs attached. | ¶74 | col. 15:26-28 |
| a control circuit operatively coupled to supply electrical pulses to the one or more LEDs | The Accused Devices have a control circuit that supplies electrical pulses to the flash. | ¶74 | col. 16:15-20 |
| that adjusts a height of the pulses to control a color spectrum of the LED output light | The complaint alleges these pulses change by "adjusting a height of the pulses to control a color spectrum." | ¶74 | col. 12:5-8 |
| and adjusts an LED on-time proportion to control an amount of the output light. | The complaint alleges the circuit "adjusts an LED on-time, thereby controlling the light output." | ¶74, ¶18 | col. 12:8-10 |
Identified Points of Contention
- Technical Questions: A key question is whether the Accused Devices actually use the specific dual-control mechanism of adjusting pulse height for color and pulse on-time for brightness. The complaint's allegations are conclusory restatements of the claim language (Compl. ¶74). A defendant may argue its system uses a different, more common technique, such as pulse-width modulation (PWM) for each individual color channel, which may not meet the "adjusts a height" limitation.
- Legal Questions: The most significant issue is that the asserted claim 19 was disclaimed by the patentee after the suit was filed. This action renders the claim permanently unenforceable, which will likely lead to the dismissal of this count as moot.
V. Key Claim Terms for Construction
Term from ’661 Patent, Claim 34: "maintain a predetermined light output level"
Context and Importance
- This term is critical because it defines the required brightness control function. The infringement analysis will depend on whether the Accused Devices' primary function of color-matching also satisfies this limitation. Practitioners may focus on this term because the defense could argue that any brightness stability is merely an incidental byproduct of its color-matching algorithm, not the result of actively "maintaining" a "predetermined" level as required by the claim.
Intrinsic Evidence for Interpretation
- Evidence for a Broader Interpretation: The specification describes maintaining an "average predetermined light output level" (’661 Patent, col. 2:27-35), which may suggest that something less than perfect, instantaneous constancy is required, potentially encompassing the overall effect of the accused color-matching feature.
- Evidence for a Narrower Interpretation: The word "predetermined" suggests a specific, pre-set target for brightness. The specification's description of embodiments that use feedback circuits to measure and adjust light output could support a narrower construction requiring an active, closed-loop control system specifically tasked with brightness stabilization (’661 Patent, col. 4:5-12).
Term from ’390 Patent, Claim 19: "adjusts a height of the pulses"
Context and Importance
- This term defines the specific mechanism for color control. The validity of the infringement allegation hinges on whether the Accused Devices literally adjust the amplitude (current or voltage) of the electrical pulses. This is a critical distinction, as many systems control color by varying the pulse width of different colored LEDs, not the pulse height.
Intrinsic Evidence for Interpretation
- Evidence for a Broader Interpretation: The specification includes Figure 6, which shows that the color spectrum of an LED changes with the level of applied current. A party could argue that "adjusts a height" should be broadly construed to mean any method of adjusting the pulse current to achieve this effect (’390 Patent, col. 12:5-14).
- Evidence for a Narrower Interpretation: The claim separately recites adjusting "on-time proportion," creating a clear distinction between modulating pulse duration and modulating pulse amplitude. The specification further describes specific circuit embodiments for "current control" that directly manipulate the pulse amplitude (’390 Patent, Fig. 7, element 755), suggesting the claim is directed to this specific technical approach, not just the end result.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement. Inducement is based on Defendants' alleged actions of "encouraging, advertising... promoting, and instructing others" on how to use the accused camera and flash systems through manuals and marketing (Compl. ¶61, ¶76, ¶91). Contributory infringement is based on the allegation that the accused camera and flash systems are not staple articles and were especially adapted for infringement (Compl. ¶63, ¶78, ¶93).
- Willful Infringement: Willfulness is alleged based on Defendants' knowledge of the patents "since at least the filing of this action" (Compl. ¶64, ¶79, ¶94). The complaint does not plead any facts suggesting pre-suit knowledge of the patents.
VII. Analyst’s Conclusion: Key Questions for the Case
- A primary legal issue will be one of enforceability and mootness: given the post-filing disclaimer of the asserted claim of the ’390 Patent, is the infringement count for that patent moot? The answer will almost certainly determine the fate of that portion of the lawsuit.
- A key evidentiary question will be one of technical mechanism: can the Plaintiff produce non-conclusory evidence that the accused Lumia flash system operates using the specific methods recited in the claims? For the ’661 Patent, this means proving the device actively "maintain[s] a predetermined light output level," and for the ’390 Patent, it would have meant proving the circuit "adjusts a height of the pulses" for color control.
- A central claim construction question will be one of functional scope: how narrowly will the court construe the phrase "maintain a predetermined light output level" in the ’661 Patent? The outcome will likely depend on whether the court finds that this language requires a primary, dedicated function of brightness stabilization or if it can be satisfied by a system where brightness stability is an ancillary effect of a different primary function, such as ambient color matching.