Coretronic Corporation v. Maxell, LTD.

Petition

Petition summary

Prosecution History analysis

Examiner Search analysis

Invalidity Framework analysis

## 1. Case Identification
- Case Number: [IPR2025-00477](https://ai-lab.exparte.com/case/ptab/IPR2025-00477)
- Patent #: [7,850,313](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1001)
- Filed: January 17, 2025
- Petitioner(s): [Coretronic Corporation](https://ai-lab.exparte.com/party/coretronic-corp) and Optoma Corporation
- Patent Owner(s): [Maxell, Ltd.](https://ai-lab.exparte.com/party/maxell-ltd)
- Challenged Claims: 1-3

## 2. Patent Overview
- Title: Projection Type Image Apparatus
- Brief Description: The [’313](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1001) patent discloses a projection apparatus for obliquely projecting an image onto a screen. The apparatus includes an image display element, a first lens group, a second lens group, a reflection mirror, and a chassis, with the key feature being two separate mounting bases for the lens groups, where the first mounting base is fixed to the chassis and the second mounting base is movable.

## 3. Grounds for Unpatentability

#### Ground 1: Claims 1 and 3 are obvious over Yamagishi ’723 in view of Itohiya ’986 and Itohiya ’759.
- **Prior Art Relied Upon:** Application # [US2006/0132723A1](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1005) ([Yamagishi ’723](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1005)), Japanese Publication # [JP2006047986A](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1006) ([Itohiya ’986](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1006)), and Application # [US2005/0275759A1](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1007) ([Itohiya ’759](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1007)).
- **Core Argument for this Ground:**
    - **Prior Art Mapping:** Petitioner argued that [Yamagishi ’723](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1005) discloses the fundamental projection apparatus of claim 1, including an image display element, two lens groups (a front group and a rear group), and a reflection mirror for oblique projection, all within a housing (chassis). However, [Yamagishi ’723](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1005) does not expressly teach separate fixed and movable mounting bases. To supply these elements, Petitioner asserted that [Itohiya ’986](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1006) teaches a projection system with both fixed lenses and a movable lens group supported on a sliding frame (a movable mounting base) to allow for precise adjustment. [Itohiya ’759](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1007) was then used to teach the claimed detail of firmly fixing the other mounting base to the bottom of the chassis via screw fastening. For dependent claim 3, Petitioner contended that the "adjustment fixing screw" in [Itohiya ’986](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1006), which actuates the movable lens frame, constitutes the claimed "rod member."
    - **Motivation to Combine:** Petitioner asserted that a person of ordinary skill in the art (POSITA) would combine these references as they are all in the same field of endeavor (projection optics). A POSITA would modify the [Yamagishi ’723](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1005) projector with the adjustable lens mechanism from [Itohiya ’986](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1006) to achieve the known benefit of precise focusing. A POSITA would then look to [Itohiya ’759](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1007), which shares an inventor with [Itohiya ’986](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1006), for known methods of securely mounting the fixed lens components to the chassis.
    - **Expectation of Success:** A POSITA would have had a reasonable expectation of success, as the combination involves integrating known mechanical adjustment and mounting techniques into a conventional projector design.

#### Ground 2: Claim 2 is obvious over Yamagishi ’723, Itohiya ’986, Itohiya ’759, and further in view of Ohzawa.
- **Prior Art Relied Upon:** [Yamagishi ’723](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1005), [Itohiya ’986](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1006), [Itohiya ’759](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1007), and Patent [6,542,204](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1008) ([Ohzawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1008)).
- **Core Argument for this Ground:**
    - **Prior Art Mapping:** This ground builds upon the combination asserted in Ground 1 to address dependent claim 2, which adds the limitation that the optical axis of the lens groups is inclined relative to a normal line at the center of the image display element. Petitioner argued that [Ohzawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1008) explicitly teaches this feature, disclosing a projection system where the optical axis is inclined at an angle (5°<θo<15°) relative to the normal of the reflection-type display device.
    - **Motivation to Combine:** A POSITA would be motivated to incorporate [Ohzawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1008)'s teachings into the projector of Ground 1 to gain significant, known benefits. [Ohzawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1008) explains that this inclined arrangement allows for the separation of illumination and projection light, thereby avoiding interference while correcting for trapezoidal distortion and coma aberration without increasing manufacturing costs.
    - **Expectation of Success:** The modification was presented as a known technique for improving projector performance, leading to a high expectation of success.

#### Ground 3: Claim 1 is obvious over Karasawa in view of Yamagishi ’706 and Itohiya ’759.
- **Prior Art Relied Upon:** Japanese Publication # [JP2003248169A](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1009) ([Karasawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1009)), Application # [US2005/0219706A1](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1010) ([Yamagishi ’706](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1010)), and [Itohiya ’759](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1007).
- **Core Argument for this Ground:**
    - **Prior Art Mapping:** Petitioner presented an alternative invalidity theory starting with [Karasawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1009) as the primary reference. [Karasawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1009) was argued to disclose a projector with multiple lens groups, a reflection mirror, an image display element, and a cabinet (chassis). [Karasawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1009) also teaches that some lenses are movable. To arrive at the claimed configuration of separate fixed and movable mounting bases, Petitioner combined this with [Yamagishi ’706](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1010), which teaches a fixed focal length system where only specific focusing lenses move while other lenses remain fixed. [Itohiya ’759](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1007) was again used to supply the teaching of fixing one of the mounting bases to the bottom of the chassis.
    - **Motivation to Combine:** A POSITA would combine [Karasawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1009)'s design with the teachings of [Yamagishi ’706](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1010) to obtain the benefits of a more reliable and less expensive system by limiting movement to only the necessary focusing lenses. [Itohiya ’759](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1007) would be consulted for known mounting techniques.
    - **Expectation of Success:** The combination was argued to be a predictable integration of known design choices in the field of projector optics.
- **Additional Grounds:** Petitioner asserted additional obviousness challenges, including combinations of [Itohiya ’759](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1007) and [Itohiya ’986](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1006) (with and without [Ohzawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1008)) and combinations based on [Karasawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1009) to challenge claims 2 and 3. These grounds relied on similar rationales, adding [Ohzawa](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1008) for the inclined axis of claim 2 and [Itohiya ’986](https://ai-lab.exparte.com/case/ptab/IPR2025-00477/doc/1006) for the rod member of claim 3.

## 4. Key Claim Construction Positions
- Petitioner argued as a threshold matter that the term "said screen" in independent claim 1 lacks an antecedent basis and renders the claim indefinite. However, for the purposes of the IPR, Petitioner proceeded to map this limitation to the screen elements disclosed in the prior art references. No other specific claim construction positions were advanced, with Petitioner stating all other terms should be given their plain and ordinary meaning.

## 5. Arguments Regarding Discretionary Denial
- Petitioner argued that discretionary denial under §325(d) is not warranted because the prior art references and combinations presented in the [petition](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/2) were not considered by the examiner during the original prosecution.
- Petitioner also argued that discretionary denial under *Fintiv* is not warranted, asserting:
    - The parallel district court litigation is in a very early stage with minimal investment by the court or parties.
    - The scheduled trial date is after the statutory deadline for a Final Written Decision (FWD), and could be delayed further.
    - Petitioner stipulated that it will not pursue the same grounds in the district court if the IPR is instituted, eliminating concerns of overlap and inefficiency.
    - The [petition](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/2) presents a compelling, meritorious challenge, weighing heavily in favor of institution to serve the efficiency and integrity of the patent system.

## 6. Relief Requested
- Petitioner requests the institution of an inter partes review and the cancellation of claims 1-3 of Patent [7,850,313](https://ai-lab.exparte.com/docs/ptab/IPR2025-00477/1001) as unpatentable.

Oblique projector patent challenged: Yamagishi & Itohiya prior art cited for obviousness of all 3 claims over known movable lens mounting systems.