Before Rich, Michel, and Lourie, Circuit Judges.
The opinion of the court was delivered by: Michel, Circuit Judge.
NOTE: Pursuant to Fed. Cir. R. 47.6, this Disposition is not citable as precedent. It is a public record. The Disposition will appear in tables published periodically.
Plaintiffs Ampex Corporation and Ampex International, S.A. ("Ampex") appeal the decision of the United States District Court for the District of Delaware in Ampex Corporation v. Mitsubishi Electric Corporation, CA No. 95-582-RMM (June 18, 1997), holding as a matter of law that Mitsubishi's accused device does not infringe United States Patent Number 4,212,027 ("the '027 patent") under the doctrine of equivalents. We affirm.
The '027 patent is entitled "Time Base Compensator" and issued on July 8, 1980. Claim 83 is the only claim at issue in this appeal, and it is reproduced below:
83. Apparatus for changing the time-base of a digital information signal having a time-base synchronizing component, comprising: a randomly addressable digital store having addressed storage locations for receiving and storing successive intervals of the digital information; means for effecting the storage of successive portions of each interval of the digital information signal at different addressed storage locations of the digital store at times determined by a clock signal; means for effecting retrieval of the stored portions of the information signal from addressed storage locations at times determined by said clock signal; and means responsive to the time-base synchronizing component of the information signal and a time-base reference signal for providing a control signal representative of the time difference between the synchronizing component and the reference signal; and means responsive to said control signal for adjusting during each interval of the digital information signal the time between effecting storage of each portion of the digital information signal at an address and effecting retrieval of said portion from said address.
'027 pat., col. 28, ll. 20-40 (emphasis added). One limitation at issue in the instant case is the "control signal" in claim 83 (emphasized above). Ampex's patent is directed to a method and apparatus for writing a signal to memory and then reading the signal from memory. The accused infringing device is used in Mitsubishi televisions with "picture-in-picture" ("PIP") technology. PIP allows viewers to watch two programs simultaneously by placing a small picture within the main picture. Mitsubishi's PIP operates by temporarily storing (writing) information relating to the subpicture signal in a digital store, or memory, and retrieving (reading) that information at an appropriate time to enable the subpicture to appear within the main picture.
The question of whether the accused device infringed the '027 patent was before the jury. The jury found equivalent infringement and awarded damages in the amount of $8,091,154. Mitsubishi moved for a judgment of noninfringement as a matter of law. Ampex moved for a judgment as a matter of law of literal infringement. The district court granted Mitsubishi's motion and denied Ampex's motion. Ampex appeals that decision in the instant case. Mitsubishi cross-appeals inter alia the failure of the district court to render a decision on the validity of claim 83, and the dismissal by the district court of its counterclaims.
The district court granted judgment of noninfringement as a matter of law based upon prosecution history estoppel. We review judgment as a matter of law de novo and affirm the judgment of noninfringement based on different grounds. Since we hold that the absence of the "control signal" limitation in the Mitsubishi device precludes as a matter of law a finding of infringement, we do not reach the merits of the district court's prosecution history estoppel holding.
Under Pennwalt Corporation v. Durand-Wayland, Inc., 833 F.2d 931, 936 (Fed. Cir. 1987) (in banc), if a single limitation of a claim or its equivalent is not present in the accused device then that device cannot infringe under the doctrine of equivalents. Claim 83 of the '027 patent requires the presence of a counter. The relevant language from the claim is quoted below:
means responsive to the time-base synchronizing component of the information signal and a time-base reference signal for providing a control signal representative of the time difference between the synchronizing component and the reference signal . . . .
'027 patent, col. 28, ll. 31-36. Because this is a means claim, under § 112, ¶ 6, the scope of the claim is limited to the structure disclosed in the specification and equivalents thereof. 35 U.S.C. § 112, ¶ 6. The relevant disclosure of the patent clearly illustrates that the structure which performs the function recited for this element of the claim is counter 168:
The relative time of occurrences is determined by a counter serving as a horizontal sync comparator 168. The counter 168 is started to count in response to the reference horizontal sync and is stopped by the occurrence of the television signal's horizontal sync. The counter 168 counts at the rate of color burst. The output of the counter 168 changes the address output by the read address generator 167 in ...