Cedar Lane Tech Inc v. Excelitas Tech Corp

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: Cedar Lane Technologies Inc. (Canada)
  • Defendant: Excelitas Technologies Corp. (Delaware)
  • Plaintiff’s Counsel: Gawthrop Greenwood, PC; Rabicoff Law LLC
• Case Identification: 1:22-cv-00011, D. Del., 01/04/2022
• Venue Allegations: Venue is alleged to be proper in the District of Delaware because Defendant is incorporated in Delaware and maintains an established place of business in the District.
• Core Dispute: Plaintiff alleges that certain Defendant products infringe two patents related to an interface for managing data transfer between a CMOS imaging array and a host processor system.
• Technical Context: The technology addresses the challenge of efficiently connecting image sensors, which produce a constant stream of data, with microprocessors, which access data on an as-needed basis, a foundational issue in digital imaging devices.
• Key Procedural History: The complaint indicates U.S. Patent No. 8,537,242 is a divisional of the application that resulted in U.S. Patent No. 6,972,790, suggesting the patents share a common specification and priority claim. No other prior litigation, licensing, or post-grant proceedings are mentioned.

Case Timeline

Date	Event
2000-01-21	Priority Date for '790 and '242 Patents
2000-12-21	'790 Patent Application Filing Date
2005-10-27	'242 Patent Application Filing Date
2005-12-06	'790 Patent Issue Date
2013-09-17	'242 Patent Issue Date
2022-01-04	Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 6,972,790 - "Host interface for imaging arrays" (Issued Dec. 6, 2005)

The Invention Explained

• Problem Addressed: The patent describes a technical incompatibility between conventional CMOS image sensors and commercial microprocessors. Sensors typically provide a continuous, high-speed "video style output" of pixel data tied to a master clock, whereas microprocessors are designed for random access to memory. Interfacing the two traditionally required "additional glue logic," which increases cost and complexity, thereby diminishing the economic and integration benefits of CMOS technology (’790 Patent, col. 1:38-66).
• The Patented Solution: The invention proposes an interface, preferably integrated onto the same semiconductor die as the image sensor, that acts as a buffer and manager between the sensor and the processor system. This interface uses a memory (e.g., a First-In-First-Out or FIFO buffer) to temporarily store image data as it is generated by the sensor. When a sufficient "quantity of data" accumulates in the memory, the interface generates a signal, such as an interrupt, to alert the processor. The processor can then read the data from the interface's memory at its own rate, decoupling the sensor's fixed-rate data capture from the processor's on-demand data retrieval (’790 Patent, Abstract; col. 2:3-14). Figure 1 illustrates this system, with interface (13) situated between the imaging array (12) and the CPU (10).
• Technical Importance: This design allows for more efficient, low-cost, and highly integrated imaging systems by eliminating the need for external interface components and allowing the host CPU to perform other tasks without being constantly occupied by the management of a raw video stream (’790 Patent, col. 1:24-31).

Key Claims at a Glance

• The complaint does not identify specific claims but refers to "Exemplary '790 Patent Claims" in an external exhibit (Compl. ¶12). Independent claim 1 is representative.
• Independent Claim 1:
  • An interface for receiving data from an image sensor having an imaging array and a clock generator for transfer to a processor system comprising:
  • a memory for storing imaging array data and clocking signals at a rate determined by the clocking signals;
  • a signal generator for generating a signal for transmission to the processor system in response to the quantity of data in the memory; and
  • a circuit for controlling the transfer of the data from the memory at a rate determined by the processor system.
• The complaint reserves the right to assert infringement under the doctrine of equivalents (Compl. ¶12).

U.S. Patent No. 8,537,242 - "Host interface for imaging arrays" (Issued Sep. 17, 2013)

The Invention Explained

• Problem Addressed: As a divisional of the '790 patent's application, the '242 Patent addresses the identical problem of the "incompatible" data interface between a CMOS image sensor's constant data stream and a microprocessor's random-access architecture (’242 Patent, col. 1:42-53).
• The Patented Solution: The '242 Patent claims a method of performing the functions of the interface system described in the '790 Patent. The claimed method involves the steps of receiving and storing image data in a FIFO memory, using a counter to track the amount of stored data, comparing that count to a predefined limit, and generating an interrupt signal to the processor when the count reaches that limit. The processor, in response, transfers the data from the memory (’242 Patent, Abstract; col. 8:55-68, Claim 1).
• Technical Importance: This patent provides protection for the operational method of the buffering and signaling process, complementing the apparatus claims of the parent '790 Patent.

Key Claims at a Glance

• The complaint does not identify specific claims but refers to "Exemplary '242 Patent Claims" in an external exhibit (Compl. ¶21). Independent claim 1 is representative.
• Independent Claim 1:
  • A method of processing imaging signals, the method comprising:
  • receiving image data from an imaging array;
  • storing the image data in a FIFO memory;
  • updating a FIFO counter to maintain a count of the image data... in response to memory reads and writes;
  • comparing the count of the FIFO counter with a FIFO limit;
  • generating an interrupt signal to request a processor to transfer image data... in response to an interrupt enable signal being valid and the count of the FIFO counter having a predetermined relationship to the FIFO limit; and
  • transferring image data from the FIFO memory to the processor in response to the interrupt signal.
• The complaint reserves the right to assert infringement under the doctrine of equivalents (Compl. ¶21).

III. The Accused Instrumentality

Product Identification

The complaint alleges infringement by "Exemplary Defendant Products" identified in chart exhibits incorporated by reference (Compl. ¶¶12, 21). These exhibits were not filed with the complaint.

Functionality and Market Context

The complaint does not provide sufficient detail for analysis of the accused products' specific functionality or market context, as these details are contained within the unfiled exhibits.

IV. Analysis of Infringement Allegations

The complaint incorporates its infringement allegations by reference to external claim chart exhibits (Exh. 3 for the '790 Patent and Exh. 4 for the '242 Patent), which were not provided (Compl. ¶¶18, 27). The body of the complaint contains only general and conclusory allegations that the accused products practice the claimed technology (Compl. ¶¶17, 26). Therefore, a detailed claim chart analysis cannot be constructed, and specific points of technical contention cannot be identified from the provided documents.

No probative visual evidence provided in complaint.

V. Key Claim Terms for Construction

'790 Patent (Claim 1)

• The Term: "in response to the quantity of data in the memory"

• Context and Importance: This term is central to the causal link between the memory's state and the signal sent to the processor. The definition will determine whether any signal generated after data is stored meets the limitation, or if a more specific triggering mechanism based on a measured "quantity" is required.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: The plain language does not specify how the quantity must be measured or what the response must be, which could support an interpretation where simply having a non-zero amount of data is a sufficient "quantity" to trigger a response.
  • Evidence for a Narrower Interpretation: The specification discloses a specific embodiment where an "increment/decrement counter" (54) tracks the data, and an "interrupt generator" (48) "compares the FIFO counter output Sc and the FIFO limit S_L" to generate the signal (’790 Patent, col. 6:1-14). A defendant may argue this detailed implementation limits the claim scope to systems with a threshold-based triggering mechanism.

• The Term: "a rate determined by the processor system"

• Context and Importance: This term defines the decoupling of the data transfer from the sensor's clock. Its construction will clarify the degree of control the processor must have over the data transfer rate.

• Intrinsic Evidence for Interpretation:

  • Evidence for a Broader Interpretation: This could be read to mean any transfer rate that is not rigidly synchronized with the sensor's clock, as the processor's availability inherently "determines" when the transfer occurs.
  • Evidence for a Narrower Interpretation: The specification describes the "CPU 10" accessing registers and the FIFO buffer "by asserting the necessary read or write commands" on the system bus (’790 Patent, col. 6:50-55). This may support a narrower construction requiring that the processor actively initiates and controls the timing of each data read operation from the interface's memory.

'242 Patent (Claim 1)

• The Term: "a predetermined relationship to the FIFO limit"
• Context and Importance: Practitioners may focus on this term because it appears more specific than the corresponding language in the '790 Patent. The dispute will center on what "relationships" (e.g., equal to, greater than, within a range of) are covered by the claim.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: "Relationship" is a general word. A plaintiff might argue it covers various logical conditions, not just a single type of comparison.
  • Evidence for a Narrower Interpretation: The shared specification discloses a clear example: "If S_c >= S_L... the generator 48 asserts the interrupt signal" (’790 Patent, col. 6:11-14). A defendant could argue this explicit "greater than or equal to" condition defines and limits the scope of the "predetermined relationship."

VI. Other Allegations

• Indirect Infringement: Plaintiff alleges induced infringement for both patents. The factual basis alleged is that Defendant sells the accused products and distributes "product literature and website materials inducing end users and others to use its products in the customary and intended manner that infringes" (Compl. ¶¶15, 24). The complaint also alleges inducement based on knowledge acquired "at least since being served by this Complaint" (Compl. ¶¶16, 25).
• Willful Infringement: The complaint does not use the word "willful" but alleges Defendant has "Actual Knowledge of Infringement" from the service of the complaint and has continued its infringing conduct despite this knowledge (Compl. ¶¶14-15, 23-24). The prayer for relief seeks enhanced damages under 35 U.S.C. § 284 and a finding that the case is "exceptional" under § 285, which are remedies for willful or egregious infringement (Compl. ¶¶ F, G). The allegations appear to be based on post-suit conduct.

VII. Analyst’s Conclusion: Key Questions for the Case

1. A central issue will be one of claim construction and scope: For the '790 Patent, can the functional language "in response to the quantity of data" be met by any system that signals a processor after some data is stored, or is it limited to the specification's embodiment of a counter compared against a specific threshold?

2. A related question for the '242 Patent's method claim will be one of definitional precision: What technical meaning will be given to "a predetermined relationship" between the data count and the FIFO limit? The answer will likely depend on whether the court finds the explicit "greater than or equal to" example in the specification to be merely illustrative or definitional.

3. An evidentiary burden for the Plaintiff will be to prove its indirect infringement claims. This will require demonstrating not only direct infringement by end-users but also that Defendant's product literature and other materials specifically instructed or encouraged users to operate the products in a manner that satisfies every element of the asserted claims, thereby showing the requisite intent for inducement.