DCT
4:22-cv-03440
KT Imaging USA LLC v. Zhejiang Dahua Technology Co Ltd
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: KT Imaging USA, LLC (Texas)
- Defendant: Zhejiang Dahua Technology Co., Ltd. (China); Zhejiang Dahua Vision Technology Co., Ltd. (China); Dahua Technology (HK) Limited (Hong Kong); Lorex Technology Inc. (Canada); Amcrest Technologies LLC (Texas)
- Plaintiff’s Counsel: Kheyfits Belenky LLP
- Case Identification: 4:22-cv-03440, S.D. Tex., 10/06/2022
- Venue Allegations: Venue is alleged to be proper as to the Dahua and Lorex defendants because they are foreign corporations, and as to Amcrest because it allegedly has a regular and established place of business in the district.
- Core Dispute: Plaintiff alleges that Defendants’ security cameras, video doorbells, and other video technology products infringe four patents related to the structure, packaging, and manufacturing of image sensor modules.
- Technical Context: The patents concern methods for fabricating and assembling the miniature camera components that convert light into electronic signals, focusing on miniaturization, cost reduction, and reliability.
- Key Procedural History: The complaint does not mention any prior litigation, Inter Partes Review (IPR) proceedings, or licensing history related to the patents-in-suit.
Case Timeline
| Date | Event |
|---|---|
| 2003-07-16 | U.S. Patent No. 6,876,544 Priority Date |
| 2004-10-08 | U.S. Patent No. 7,196,322 Priority Date |
| 2005-04-05 | U.S. Patent No. 6,876,544 Issued |
| 2005-05-18 | U.S. Patent No. 8,314,481 Priority Date |
| 2007-03-27 | U.S. Patent No. 7,196,322 Issued |
| 2008-05-16 | U.S. Patent No. 8,004,602 Priority Date |
| 2011-08-23 | U.S. Patent No. 8,004,602 Issued |
| 2012-11-20 | U.S. Patent No. 8,314,481 Issued |
| 2022-10-06 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,876,544 - Image Sensor Module and Method for Manufacturing the Same
- Issued: April 5, 2005
The Invention Explained
- Problem Addressed: The patent describes conventional image sensor manufacturing as inconvenient and costly due to the short distances for wire bonding, the risk of particle contamination on the transparent cover, and the high number of components, specifically requiring a separate lens holder to which a lens barrel is screwed (’544 Patent, col. 1:42-62).
- The Patented Solution: The invention proposes a more integrated and simplified design. It uses a single "frame layer" that is mounted on the substrate to surround the photosensitive chip. This frame layer is formed with an internal thread, and it also serves to fix a transparent layer in place. A lens barrel with a corresponding external thread can then be screwed directly into this frame layer, eliminating the need for a separate lens holder component ('544 Patent, col. 2:5-14, FIG. 2).
- Technical Importance: This approach aimed to reduce the number of discrete components in an image sensor module, which could simplify manufacturing processes and lower costs ('544 Patent, col. 2:1-5).
Key Claims at a Glance
- The complaint asserts infringement of at least claim 1 (Compl. ¶25).
- Independent Claim 1 requires:
- A substrate with upper and lower connection points.
- A photosensitive chip mounted on the substrate's upper surface.
- Wires connecting the chip to the substrate's connection points.
- A frame layer mounted on the substrate to surround the chip, where the frame layer has an internal thread and fixes a transparent layer.
- A lens barrel with an external thread that screws into the internal thread of the frame layer.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 7,196,322 - Image Sensor Package
- Issued: March 27, 2007
The Invention Explained
- Problem Addressed: The patent identifies a problem in packaging large-scale photosensitive chips. As chips get larger, connecting wires from the chip to the underlying substrate becomes difficult or impossible, forcing manufacturers to use an even larger, more expensive substrate just to create enough space for wire bonding (’322 Patent, col. 1:30-36).
- The Patented Solution: The invention repositions the electrical connection points. Instead of placing them on the substrate, it introduces a "frame layer" on the substrate, and forms the connection points ("first electrodes") on the upper surface of this frame layer. The photosensitive chip is placed inside the cavity formed by the frame, and wires connect the chip outwards to the electrodes on the frame layer, providing more space. A lens holder is then adhered over this assembly ('322 Patent, Abstract; col. 2:13-30).
- Technical Importance: By moving the wire-bonding pads from the substrate to a surrounding frame, this design allows for the packaging of different sized sensor chips without changing the overall package volume or requiring a larger substrate ('322 Patent, col. 2:44-48).
Key Claims at a Glance
- The complaint asserts infringement of at least claim 1 (Compl. ¶30).
- Independent Claim 1 requires:
- A substrate with an upper surface and a lower surface having electrodes.
- A frame layer on the substrate's upper surface, forming a cavity, with a plurality of "first electrodes" formed on the frame layer itself.
- A photosensitive chip in the cavity, electrically connected to the "first electrodes" on the frame layer.
- A lens holder with a threaded opening, adhered to the substrate, where the frame layer is located within a "breach" at the bottom of the lens holder.
- A lens barrel screwed into the lens holder.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 8,004,602 - Image Sensor Structure and Integrated Lens Module Thereof
- Issued: August 23, 2011
Technology Synopsis
The patent describes an image sensor structure designed to reduce size and simplify manufacturing. The key problems it addresses are the space required for traditional wire-bonding and the complexity of aligning a separate lens barrel (’602 Patent, col. 1:12-21, 55-65). The solution involves a chip with a "conducting channel" (e.g., a through-silicon via) that passes from the top to the bottom, eliminating the need for top-surface wire bonds. It also discloses a lens module where at least one lens is "completely embedded" and integrated with its holder, which is then combined directly with the chip's surface ('602 Patent, Abstract).
Asserted Claims
At least claim 1 (Compl. ¶35).
Accused Features
The complaint alleges that products like the Dahua 4MP Mini Bullet Network Camera infringe by including an image sensor with a chip having a conducting channel and a lens module with a holder and an embedded lens integrated with the holder (Compl. ¶35).
U.S. Patent No. 8,314,481 - Substrate Structure for an Image Sensor Package and Method for Manufacturing the Same
- Issued: November 20, 2012
Technology Synopsis
The patent addresses a reliability problem where particles and moisture can enter the sensor package through passages between the electrodes during manufacturing (’481 Patent, col. 1:34-39). The proposed solution is a substrate structure including a "bottom base" with electrodes, an "insulation layer" (such as green paint) coated between the electrodes on the upper surface of the base, and a "frame layer" arranged on top. The insulation layer is "interposed between the bottom base and the frame layer," effectively sealing the assembly ('481 Patent, Abstract; col. 2:13-21).
Asserted Claims
At least claim 1 (Compl. ¶40).
Accused Features
The complaint alleges that products like the Dahua 2MP WiFi Video Doorbell infringe by including a substrate structure with a bottom base, an insulation layer coated between electrodes, and a frame layer arranged on top of the insulation layer and electrodes (Compl. ¶40-41).
III. The Accused Instrumentality
Product Identification
The accused instrumentalities are a range of "video technology products, such as security cameras and/or video doorbells, with image sensors" (Compl. ¶22). Specific examples cited include the "Amcrest 4MP USB Webcam (AWC496)," the "Dahua 4MP IR 3.6mm ePoE Mini Bullet Network Camera (N44CB33)," and the "Dahua 2MP WiFi Video Doorbell (DHI-DB11)" (Compl. ¶25, 30, 35, 40).
Functionality and Market Context
The complaint focuses on the physical construction of the image sensor modules within these products. The core functionality at issue is how the photosensitive chip, substrate, wiring, and lens assembly are physically packaged together (Compl. ¶25, 30, 35, 40-41). The complaint alleges that the defendants "make, use, sell, offer for sale, or import" these products in the United States (Compl. ¶22).
IV. Analysis of Infringement Allegations
U.S. Patent No. 6,876,544 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a substrate having an upper surface formed with a plurality of first connection points, and a lower surface formed with a plurality of second connection points, which is electrically connect to the printed circuit board | The accused products' image sensor module comprises a substrate with an upper surface having first connection points and a lower surface with second connection points, electrically connected to a printed circuit board. | ¶25 | col. 4:5-10 |
| a photosensitive chip mounted to the upper surface of the substrate | A photosensitive chip is mounted to the upper surface of the substrate. | ¶25 | col. 4:11-12 |
| a plurality of wires for electrically connecting the photosensitive chip to the first connection points on the upper surface of the substrate | A plurality of wires electrically connects the photosensitive chip to the first connection points on the substrate's upper surface. | ¶25 | col. 4:13-16 |
| a frame layer mounted to the upper surface of the substrate to surround the photosensitive chip, an inner edge of the frame layer being formed with an internal thread from top to bottom, and a transparent layer being fixed by the frame layer... | A frame layer is mounted on the substrate to surround the chip, with an inner edge formed with an internal thread, and a transparent layer is fixed by the frame to allow optical signals to pass through. The complaint describes this with a visual reference to a cross-sectional image of the Amcrest 4MP USB Webcam image sensor (Ex. 2). | ¶25 | col. 4:17-24 |
| a lens barrel formed with a chamber at a center thereof and an external thread at an outer edge thereof, the external thread being screwed to the internal thread of the frame layer... | A lens barrel with an external thread is screwed to the internal thread of the frame layer. | ¶25 | col. 4:25-30 |
Identified Points of Contention
- Technical Question: What evidence demonstrates that the accused "frame layer" both (1) fixes the transparent layer in place and (2) directly receives the threaded lens barrel, as required by the claim, rather than using an intermediate lens holder? The complaint's allegations group these features together, but their structural relationship will be a key factual determination.
U.S. Patent No. 7,196,322 Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a substrate having an upper surface, and a lower surface on which second electrodes are formed | The image sensor module includes a substrate with an upper surface and a lower surface with second electrodes. This is shown in a cross-sectional image of the Amcrest 4MP USB Webcam image sensor (Exs. 1, 2). | ¶30 | col. 4:51-53 |
| a frame layer arranged on the upper surface of the substrate, a cavity formed between the frame layer and substrate, and a plurality of first electrodes are formed on the frame layer | A frame layer is arranged on the substrate's upper surface, forming a cavity. First electrodes are formed on this frame layer. This is shown in an image of the Amcrest 4MP USB Webcam image sensor with internal components exposed (Ex. 3). | ¶30 | col. 4:54-59 |
| a photosensitive chip mounted on the upper surface of the substrate and located within the cavity, and electrically connected to the first electrodes of the frame later [sic] | A photosensitive chip is mounted on the substrate within the cavity and is electrically connected to the first electrodes on the frame layer. | ¶30 | col. 4:60-63 |
| a lens holder having an upper end face, a lower end face, and an opening... formed with a breach... wherein, the frame layer is located within the breach of the lens holder | A lens holder with an opening is adhered to the substrate. The opening has a lower end formed with a "breach," and the frame layer is located within this breach. | ¶30 | col. 3:1-10 |
| a lens barrel having an upper end face, a lower end face, and an external thread screwed to the internal thread of the lens holder | A lens barrel with an external thread is screwed into the internal thread of the lens holder. | ¶30 | col. 3:11-15 |
Identified Points of Contention
- Scope Question: A central issue may be the meaning of "first electrodes are formed on the frame layer." Does this require the electrodes to be monolithically part of or deposited directly onto the frame layer material, or could it cover a configuration where separate electrical contacts are merely supported by the frame?
- Technical Question: What is the structure and function of the accused "breach"? The claim requires the frame layer to be "located within the breach," suggesting a specific physical interface between the lens holder and the frame that will require evidentiary support.
V. Key Claim Terms for Construction
For the '544 Patent
- The Term: "frame layer"
- Context and Importance: This term is the central element of the asserted claim. Its construction will determine whether the invention is limited to a single, multi-function component that replaces the conventional two-part lens holder and frame. Practitioners may focus on whether this term implies a single, unitary structure that performs both the function of holding the transparent layer and providing the threads for the lens barrel.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The claim language recites a "frame layer" with certain features (internal thread, fixing a transparent layer), which could be read as a functional description rather than a strictly structural one.
- Evidence for a Narrower Interpretation: The patent repeatedly contrasts its invention with the prior art's use of a separate "lens holder" ('544 Patent, col. 1:21-22, col. 1:59-62). The summary states that forming the thread in the frame layer "may replace the provision of the conventional lens holder" ('544 Patent, col. 3:55-57), which suggests the "frame layer" is distinct from, and a replacement for, a separate holder.
For the '322 Patent
- The Term: "breach"
- Context and Importance: The location of the frame layer "within the breach of the lens holder" is a key limitation defining the physical assembly of the package. The interpretation of "breach" will be critical to determining infringement, as it describes the specific interface between the lens holder and the underlying frame/substrate assembly.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The term is not commonly used in this context, and the specification provides limited definition, which could support an argument for a meaning encompassing any recess or cutout at the bottom of the lens holder that accommodates the frame layer.
- Evidence for a Narrower Interpretation: The patent states that "the breach 74 of the opening 71 is a triangular form" ('322 Patent, col. 2:36-37). While this is from a specific embodiment, it provides the only concrete structural definition of the term, which a party could argue limits the scope of "breach" to a feature with a similar shape or function.
VI. Other Allegations
- Indirect Infringement: The complaint alleges induced infringement for all four patents. The basis for inducement is the allegation that Defendants provide the accused products along with "specifications, instructions, manuals, advertisements, marketing materials, and technical assistance relating to the installation, set up, use, operation, and maintenance" which allegedly encourage infringement by partners, resellers, and end users (Compl. ¶26, 31, 36, 41).
- Willful Infringement: The complaint does not contain an explicit count for willful infringement, nor does it allege pre-suit knowledge of the patents-in-suit.
VII. Analyst’s Conclusion: Key Questions for the Case
- A primary issue will be one of component definition: For the '544 patent, does the accused assembly use a single, integrated "frame layer" that both holds a transparent cover and directly engages the lens barrel's threads, or does it use a more conventional multi-component structure that falls outside the claim?
- A second core issue will involve locational precision: For the '322 patent, can the plaintiff prove that the accused devices have electrical contacts "formed on the frame layer" itself, rather than on the substrate underneath? This distinction appears central to the patent's claimed solution to the wire-bonding problem.
- A key evidentiary question across all asserted patents will be one of structural mapping: The complaint relies on descriptions of visual exhibits (e.g., Ex. 1-10) to map product features to claim limitations. The case will likely depend on whether discovery and expert analysis validate these high-level descriptions and confirm the specific, claimed structural relationships within the microscopic assemblies of the accused products.