Standard Coil Products Co. v. General Electric Company

• Decision Date: 06 August 1962
• Docket Number: No. 367,Docket 27446.,367
• Citation: 306 F.2d 319
• Parties: STANDARD COIL PRODUCTS CO., Inc., Plaintiff-Appellant, v. GENERAL ELECTRIC COMPANY, Defendant-Appellee.
• Court: U.S. Court of Appeals — Second Circuit

306 F.2d 319 (1962)

STANDARD COIL PRODUCTS CO., Inc., Plaintiff-Appellant, v. GENERAL ELECTRIC COMPANY, Defendant-Appellee.

No. 367, Docket 27446.

United States Court of Appeals Second Circuit.

Argued June 6, 1962.

Decided August 6, 1962.

Samuel Ostrolenk, of Ostrolenk, Faber, Gerb & Soffen, New York City (Marc S. Gross, of Ostrolenk, Faber, Gerb & Soffen, New York City, on the brief), for plaintiff-appellant.

John Hoxie, of Davis, Hoxie, Faithfull & Hapgood, New York City (Harvey M. Brownrout, of Davis, Hoxie, Faithfull & Hapgood, New York City, and Donald N. Timbie, Syracuse, N. Y., on the brief), for defendant-appellee.

Before CLARK, WATERMAN, and MOORE, Circuit Judges.

CLARK, Circuit Judge.

Plaintiff-appellant, Standard Coil Products Co., Inc., appeals from a judgment of the district court adjudging its patent Nelson No. 2,775,659 invalid for want of invention and alternatively not infringed by defendant's accused television amplifiers. Since we conclude that plaintiff's patent is invalid, we affirm. We reach this conclusion by analyzing the technical problems of television reception here involved to find a lack of adequate disclosure of any new invention and a lack of novelty in what was stated in the patent. This is substantially the approach of the trial judge — with whose views we are in accord — except that he went on to find no infringement, an issue we do not reach.

The relevant portions of the patent in question deal with a coupling circuit in a television amplifier. The amplifier described is a two-stage type, utilizing two vacuum tubes known as triodes and linked in a manner known as a "cascode."¹ Plaintiff claims that the Nelson patent prescribes a specific form of coupling between these tubes by the use of which optimum performance in the amplification of television signals can be achieved. To resolve the issues raised by this appeal we must turn first to the technical background of the Nelson patent.

The patent arose out of the attempts by the television industry to solve the problem of "snow" on television screens in fringe areas. "Snow" (or "noise") is what television engineers call the signal distortion caused by certain inherent irregularities in the components of television amplifiers.² These intrinsic distortions have little effect when the signals are strong, but can prove serious in the case of weak signals. The presence of "snow" on the screens of sets in fringe areas where signals were weak created a problem in the early days of television. The solution to this problem, as reflected by amplifiers such as those of both the plaintiff and defendant, was to increase the signal amplification and thus decrease the relative importance of the distortion.

The cascode amplifier had been developed during World War II by a group at the Massachusetts Institute of Technology who were trying to solve the noise problem in the amplifiers used in radar receivers. It was found that the cascode arrangement gave the best performance from a noise-reduction standpoint. Since television, like radar, operates at high frequencies, it was clear that this arrangement might similarly solve the "snow" problem in television.

There is, however, a fundamental difference between the operation of radar and television amplifiers, due to the wide frequency band of the latter, which complicated the adoption of the cascode principle. The tubes in an amplifier have what is known as a capacitance — the ability to retain electrostatic charges. This capacitance has a tendency to impede the flow of electric current, and thus decrease the system's ability to amplify the current passing through it. The impedance caused by a tube's capacitance is not a fixed quality; it increases with the frequency of the signal passing through the tube. Thus the higher the frequency the less amplification a tube will give. This effect can be offset by the introduction of a coil into the circuit. A coil has a quality known as inductance. An inductance presents an impedance to the flow of current, which also varies with the frequency of the current passing through the circuit. But this impedance operates in the opposite direction as the capacitance of the tube and also decreases as the signal frequency increases. Since its effect is directly opposite to that of a capacitator the coil can offset the amplification-dampening effect of the tube. There is, moreover, one specific frequency where the opposing effects (reactances) of a given coil and capacitator are equal — this is said to be the resonating frequency, and the circuit is said to be resonant. If the elements are connected in series the circuit will produce the least opposition to current at that point; if they are linked in parallel the circuit presents the maximum opposition and no current will flow through it.

The principle of resonance can be applied to offset the effect on amplification of high frequency signals. If a coil is introduced which will resonate with the tube at the desired frequency, amplification will be increased in the vicinity of the resonating frequency. This principle was recognized in radar cascodes, which incorporated coils tuned to the operating frequency of the radar receiver. It is in the adoption of this resonance principle from radar to television, however, that the differences between the two became relevant. Radar operates on a very narrow range of frequencies, while television signals are broadcast on a wide frequency band; channels 2-6 range from 54 to 86 megacycles, and channels 7-13 range from 174 to 216 megacycles. Since a given capacitance and inductance resonate at only one frequency, it seemed as though the radar approach could be adopted to television only by using many separate coils which would be tuned to resonate with the fixed tube capacitances at various frequencies. Such a system, however, would necessitate an elaborate switching mechanism so that the amplifier could be shifted from one coil to another as the frequency increased.

In his patent, Nelson, an employee of the plaintiff, claimed that such an expensive switching mechanism was unnecessary. He claimed to have discovered a very simple circuit which would permit the use of the low-noise cascode amplifiers developed for radar and still give high levels of amplification at all the television frequencies. The heart of the circuit described by the patent was an inductor coupling the two triodes and "* * * being proportioned to provide a negligible effect upon the passage of lower frequency channels of the lower band of TV frequencies * * * and to provide an inductance value that resonates with said driven triode cathode capacitance at a frequency near the higher frequency portion of said second band to increase the system amplification of higher frequency channels of said second band." This is the statement in Claim 12 of the patent, the single claim in issue here.

The parties disagree on the interpretation to be given this claim. Resolution of this threshold question of interpretation is crucial to the outcome of this appeal, for the issues of the patent's validity and possible infringement hinge on a determination of the subject matter of this patent.

This is the issue: Defendant asserts that Nelson attempted to patent what amounts to a scientific principle — the principle that a coil which resonates with the capacitance of the second tube of a cascode television amplifier will, by virtue of such resonance, give broad band and increased high frequency amplification. Thus the patent is read by defendant as merely describing a rig in which such resonance occurs. On the other hand, plaintiff asserts that Nelson was not attempting to describe a principle or a device operating on a certain principle. It construes Claim 12 and the related specifications as establishing no more than a formula for selecting a coil which will give the desired results when utilized in a working system. The discussion of resonance is explained not as an attempt to describe what happens in the operating amplifier, but as a shorthand method of telling an engineer the calculations he must make in order to select the correct coil. In fact a well-known formula describes the relationship between a given frequency and the inductance and capacitance which resonate at that frequency. To take an example stressed by plaintiff's expert in his testimony, given a capacitance (the rating of tube 2) and a frequency (216 megacycles or thereabouts), a simple computation will yield a figure for the resonating coil. It is that computation, and nothing more, that plaintiff claims Nelson "invented," and thus constitutes the subject of its patent. Plaintiff disavows any assertion that the amplifier achieves the desired functional results because of an actual resonance of the kind mentioned in the patent. Indeed, plaintiff's expert witness admitted that the resonance principle alluded to in the Nelson patent is not the principle upon which its own amplifier or defendant's accused amplifiers work.³ As plaintiff conceives Nelson's contribution, it was not in discovering that a coil would do the job, or why a coil would do the job, but in teaching the method to use to pick the right coil.

Thus plaintiff reads the patent as saying: A single coil interstage coupling will give the high amplification desired — to pick the right coil, treat it as if it were to resonate with tube 2 at 216 megacycles. For scientific reasons (not wholly made clear) such a coil gives the right results. Defendant says no; the patent states: Build an amplifier with an inductance which actually resonates with tube 2 at 216 megacycles or thereabouts and one will get the desired amplification.

After a lengthy trial and a full examination of the patent the trial court concluded that defendant's interpretation was the correct one. We agree with that decision. The claim quoted above and many of the specifications indicate that Nelson was describing the...