Full opinion text
OPINION AND ORDER FEIKENS, District Judge. Introduction Before me is a multi-patent infringement dispute between competitors in the light emitting diode (“LED”) traffic signal industry. At issue are summary judgment motions regarding patent noninfringement and validity filed by defendants Dialight Corporation (“Dialight”), Ecolux, Inc. (“Ecolux”), Precision Solar Controls, Inc. (“Precision”), Lumileds Lighting BV (“Lu-mileds”), Philips Lighting BV (“Philips”), and Hewlett-Packard Company (“Hewlett-Packard”). I. Background All parties are involved in the design, development, manufacture, assembly, and/or sales of LED traffic signals. Most traffic signals in the United States use incandescent light bulbs, which produce light by heating a filament in the bulb’s vacuum chamber with electric current. The heated filament gives off light. Simple incandescence is inefficient, however, since it wastes most of the electrical energy it consumes as heat. LEDs offer a solution to this problem because they do not use a heated filament to produce light. Instead they use a tiny piece of specially formulated semiconductor material that emits light when an electric current passes through it. LEDs have existed for decades, and so has knowledge of their energy savings advantage over incandescent bulbs, but their use in traffic signals is a relatively new application. On June 27, 1996, Peter Hochstein, a Relume employee, filed a patent application with the U.S.Patent Office, in which he claimed a variety of power supply inventions for retrofit LED arrays, i.e., arrays that can replace incandescent bulbs in devices originally built for incandescent illumination. On August 26, 1997, the Patent Office issued that application as U.S.Patent No. 5,661,645 (“the ’645 patent”). The '645 patent lists Hochstein as its inventor. On January 10, 1997, Hochstein filed another patent application with the Patent Office, in which he claimed various inventions related to a temperature compensation circuit for LEDs. This circuit functions as a feedback loop to prevent an LED’s light intensity from decreasing as temperature increases. On July 21, 1998, the Patent Office issued this second application as U.S.Patent No. 5,783,909. The ’909 patent lists Hochstein as its inventor. Relume’s suit against defendants alleges infringement of its ’645 and ’909 patents. All defendants have argued in response that their accused products do not infringe Relume’s patents. Three defendants — Lu-mileds, Philips, and Hewlett-Packard (collectively “Lumileds”) — have also argued that Relume’s patents are invalid and unenforceable in light of relevant prior art Relume did not make available to the Patent Office during the prosecution of its patents. Defendants’ summary judgment motions address these issues. Relume has filed no summary judgment motions. II. Summary Judgment Standard Federal Rule of Civil Procedure 56(c) provides that a summary judgment shall issue “if the pleadings, depositions, answers to interrogatories, and admissions on file, together with the affidavits, if any, show that there is no genuine issue as to any material fact and that the moving party is entitled to a judgment as a matter of law.” A genuine issue of material fact does not exist “[wjhere the record taken as a whole could not lead a rational trier of fact to find for the nonmoving party.” Matsushita Elec. Indus. Co. v. Zenith Radio Corp., 475 U.S. 574, 587, 106 S.Ct. 1348, 89 L.Ed.2d 538 (1986). The movant has the initial burden of showing that no genuine issue of material fact exists. See Celotex Corp. v. Catrett, 477 U.S. 317, 323, 106 S.Ct. 2548, 91 L.Ed.2d 265 (1986); see also Fed.R.Civ.P. 56(c). Once the movant meets this initial burden, the nonmovant “must set forth specific facts showing that there is a genuine issue for trial.” Fed.R.Civ.P. 56(e). These specific facts must constitute “sufficient evidence favoring the nonmoving party.” Anderson v. Liberty Lobby, Inc., 477 U.S. 242, 249, 106 S.Ct. 2505, 91 L.Ed.2d 202 (1986). Evidence that is “merely col-orable” or “not significantly probative” will not demonstrate a need for trial. Id. at 249-50, 106 S.Ct. 2505. Likewise, “[t]he mere existence of a scintilla of evidence in support of the [nonmovant’s] position will be insufficient; there must be evidence on which the jury could reasonably find for the [nonmovant].” Id. at 252, 106 S.Ct. 2505 (emphasis added). The essence of the summary judgment inquiry is this: “whether the evidence presents a sufficient disagreement to require submission to a jury or whether it is so one-sided that one party must prevail as a matter of law.” Id. at 251-52, 106 S.Ct. 2505. In addressing this inquiry, I must view the evidence, and all reasonable inferences drawn from it, “in the light most favorable to the party opposing the motion.” Matsushita, 475 U.S. at 587, 106 S.Ct. 1348. III. Literal Infringement In their summary judgment motions, all defendants assert literal noninfringement of claims 1, 2, 4, 5, and 6 of the ’645 patent. As to the ’909 patent, all defendants except Precision assert literal noninfringement of claims 1 and 10 — the independent claims of that patent. Defendants also assert noninfringement of the ’645 and ’909 patents under the doctrine of equivalents. For Relume to establish literal infringement, “every limitation set forth in a claim must be found in the accused product or process exactly.” Becton Dickinson and Co. v. C.R. Bard, Inc., 922 F.2d 792, 796 (Fed.Cir.1990). Determining literal infringement is a “two-step process.” Id. As a first step I must determine the meaning and scope of the claims in dispute: a step “more commonly known as claim construction.” Markman v. Westview Instruments, Inc., 52 F.3d 967, 976 (Fed.Cir.1995). The second step requires me to compare the construed claims with the product or process accused of infringement. Id. The first step is a question of law, see id. at 979, while the second step is a question of fact, see North American Vaccine v. American Cyanamid Co., 7 F.3d 1571, 1574 (Fed.Cir.1993). When construing a claim under the first step, I must consider the intrinsic evidence of record: the claim language, the specification, and, if produced, the prosecution history. See Markman, 52 F.3d at 979. “The appropriate starting point, however, is always with the language of the asserted claim itself.” Phonometrics, Inc. v. Northern Telecom, Inc., 133 F.3d 1459, 1464 (Fed.Cir.1998). This is so because “[t]he language of the claims ... defines the bounds of the patentee’s exclusive rights.” Wiener v. NEC Electronics, Inc., 102 F.3d 534, 539 (Fed.Cir.1996). In construing the claim language at issue, I am guided by the principle that “claim language is interpreted to ascertain the meaning that a person of ordinary skill in the art would give to the claims in dispute.” Schering Corp. v. Amgen, Inc., 18 F.Supp.2d 372, 380 (D.Del.1998) (citing Wiener, 102 F.3d at 539). Although words in a claim generally have their ordinary meaning, “a patentee may choose to be his own lexicographer and use terms in a manner other than their ordinary meaning, as long as the special definition of the term is clearly stated in the patent specification or file history.” Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed.Cir.1996). Even when a patentee does not give a word a special meaning, the specification still “acts as a dictionary when it expressly defines terms used in the claims or when it defines terms by implication.” Id. As such, the specification is often “the single best guide to the meaning of a disputed term.” Id. If the intrinsic evidence does not resolve the ambiguities of disputed claim language, I may then consider extrinsic evidence, such as expert testimony regarding how those skilled in the art would interpret the disputed claim. See id. at 1583. While extrinsic evidence may be used “as an aid in arriving at the proper construction of the claim,” it “may not be used to vary or contradict the otherwise unambiguous meaning of the claim.” Desper Products, Inc. v. QSound Labs., Inc., 157 F.3d 1325, 1333 (Fed.Cir.1998). In most cases, intrinsic evidence will suffice to resolve ambiguity, and so, in those cases, consideration of the extrinsic evidence for construction purposes would be “improper.” See Vitronics, 90 F.3d at 1583. Based on the record before me, I am satisfied that I can “independently assess the claims, the specification, and if necessary the prosecution history, and relevant extrinsic evidence, and declare the meaning of the claims.” Exxon Chemical Patents, Inc. v. Lubrizol Corp., 64 F.3d 1553, 1556 (Fed.Cir.1995). The claims I interpret are those the parties have debated with respect to their meaning and scope. I will not refer to any prosecution history because no party has placed it in issue. I emphasize that my Markman construction of the disputed claims serves only to determine the meaning a person of ordinary skill in the art would give to those claims. See Wiener, 102 F.3d at 539. IV. Claim Construction A. The’645 Patent Relume’s ’645 patent describes an apparatus for supplying regulated voltage d.c. electrical power to an LED array. The patent has twenty-three claims, but only claims 1, 2, 4, 5, and 6 are at issue in the parties’ summary judgment motions. These five claims read as follows: 1. An apparatus for supplying regulated voltage d.c. electrical power to an LED array comprising: a rectifier means (32) having an input and an output, said rectifier means (32) being responsive to a.c. power at said input for generating rectified d.c. power at said output; a power factor correction converter means (38) having an input connected to said output of said rectifier means (32) and an output, said power factor correction converter means (38) being responsive to said rectified d.c. power at said power factor correction converter means input for generating regulated voltage d.c. power at said power factor correction converter means output; and an LED array (12) having an input connected to said output of said power factor, correction converter means (38) for receiving said regulated voltage d.c. power to illuminate said LED array (12). 2. The apparatus according to claim 1 wherein said power factor correction converter means (38) is a power factor correcting and voltage regulating buck/ boost switchmode converter. # sji # ifr ‡ 4. The apparatus according to claim 1 including an electromagnetic interference filter means (28) connected to said input of said rectifier means (32)' for preventing conducted interference from feeding back onto a.c. power lines (22) connected to said rectifier means input. 5. The apparatus according to claim 1 including an adaptive clamp circuit means (24) connected to said input of said rectifier means (32) for eliminating leakage current problems. 6. The apparatus according to claim 5 wherein said adaptive clamp circuit means (24) has an input adapted to be connected to a pair of a.c. power lines (22), a pair of clamp circuit output lines (26) connected to said adaptive clamp circuit means input, a voltage sensing means (48) connected across said input of said adaptive clamp circuit means (24), and a controlled load means (50) connected across said clamp circuit output lines (26) and to said voltage sensing means (48), said voltage sensing means (48) being responsive to a magnitude of a.c. voltage at said adaptive clamp circuit means input lower than a predetermined magnitude for turning on said controlled load means (50) to connect a low impedance load (60) in said controlled load means (50) across said clamp circuit output lines (26) and said voltage sensing means (48) being responsive to a magnitude of the a.c. voltage at said adaptive clamp circuit means input equal to or greater than said predetermined magnitude for turning off said controlled load means (50) to disconnect said low impedance load (60) from said clamp circuit output lines (26). ’645, 13:16 to 14:18. 1. Claim 1 a. “LED array” The parties’ dispute over claim l’s “LED array” concerns its configuration and components. Ecolux, Dialight, and Precision argue that the “LED array” requires a series-parallel configuration of strings of LEDs with a ballast resistor in each string. Lumileds supports this construction, but also argues that if I reject it, the plain meaning of “LED array” requires only a group of LEDs forming a complete unit — a broad construction that could encompass a single string of LEDs in series or a series-parallel configuration. Relume contends that the “LED array” requires a series-parallel configuration, but not ballast resistors. The parties’ proposed constructions all draw on the specification of the ’645 patent for primary support. Ecolux, Dialight, and Precision find their construction of “LED array” in a specification passage that describes the array’s preferred embodiment: “The LED array 12 includes a plurality of strings of series connected LEDs 14 with a ballasting resistor 16 (Rl, R2, R3, R4, R5, ...) connected in each string.” ’645, 5:5-8. Figure 5 of the patent diagrams this preferred embodiment of the array. Numeral 12 of Figure 5 labels the LED array as all components to the right of a vertical dash line. It also refers to the specification passage relied on by the defendants and to the phrase “LED array” in the language of claim 1. Relume finds its proposed construction in a different passage of the specification than do defendants. That passage describes the preferred embodiment of the LED array as “consisting of a large number of series-parallel connected LED devices.” ’645, 6:24-25. Relume also relies on the patent’s diagrams of three prior art LED arrays, all of which depict series-parallel configurations, but only one of which depicts ballast resistors. From these references — the preferred embodiment passage and the prior art diagrams — Relume argues that a person of ordinary skill in the art of LED array power supplies would understand the series-parallel configuration, but not the ballast resistors, to be a necessary part of the claimed “LED array”. My construction of “LED array” must begin with the language of claim 1. See Phillips Petroleum Co. v. Huntsman Polymers Corp., 157 F.3d 866, 871 (Fed.Cir.1998). It does not mention series-parallel LED configurations or ballast resistors. All that claim 1 explicitly requires the “LED array” element to have as physical structure is 1) the LEDs in an array arrangement and 2) an input connected to the output of the power factor correction converter means. In fact, claim 1 speaks broadly of its claimed invention. It states at the outset that it covers “[a]n apparatus for supplying regulated voltage d.c. electrical power to an LED array.” ’645, 13:16-17. It further states that this apparatus has three major elements: a rectifier means, a power factor correction converter means, and an LED array. Thus, upon reading claim 1 in its entirety, a person of ordinary skill in this art would understand that it covers a certain kind of regulated voltage power supply for an LED array, but would not necessarily conclude that the invention’s application was restricted solely to traffic signals. To put it another way, the invention described by the language of claim 1 is a relatively simple one with potentially broad application: any conceivable use for regulated voltage LED illumination. This point is important because it informs the ordinary meaning of the phrase “LED array.” By itself, the word “array” connotes nothing more than a series or orderly grouping of things. Webster’s Third New International Dictionary (1986) (hereafter “Webster’s ”) defines it variously as “a regular and imposing grouping or arrangement” and “an impressive list, series, or group of things.” The modifier “LED” simply tells the reader that the things arranged by the array are LEDs. Together, then, the words “LED” and “array” have a range of ordinary meaning that can cover LED configurations as simple as a string of LEDs in a series or as complicated as the series-parallel LED strings of the ’645 patent’s preferred embodiment. The entirety of claim 1 does not alter this range of ordinary meaning. Thus, after reading claim 1, a person- of ordinary skill in the art of LED array power supplies would understand the phrase “LED array,” on its face, to cover a wide scope of LED configurations, including, but not limited to, the simple series and the series-parallel. The parties’ proposed constructions for “LED array” raise the issue whether the specification narrows the phrase’s ordinary meaning. According to the United States Court of Appeals for the Federal Circuit (“Federal Circuit”), I “must presume that the terms in a claim mean what they say, and, unless otherwise compelled, give full effect to the ordinary and accustomed meaning of claim terms.” Johnson Worldwide Assocs., Inc. v. Zebco Corp., 175 F.3d 985, 989 (Fed.Cir.1999). The Federal Circuit has identified “two situations where a sufficient reason exists to require the entry of a definition of a claim term other than its ordinary and accustomed meaning.” Id. at 990. “The first arises if the patentee has chosen to be his or her own lexicographer by clearly setting forth an explicit definition for a claim term.” Id. “The second is where the term or terms chosen by the patentee so deprive the claim of clarity that there is no means by which the scope of the claim may be ascertained from the language used.” Id. This second situation is not at issue here because, as I have explained, the phrase “LED array” is clear on its face. The ballast resistor construction of “LED array” proposed by defendants is essentially an argument under the first situation. That is, defendants believe that the drafter of the ’645 patent acted as his/her own lexicographer and clearly set forth an explicit definition of “LED array” in the specification that requires ballast resistors. At a March 22, 1999 healing, I stated an inclination for a preliminary construction of “LED array” that was consistent with defendants’ construction. After further consideration, however, I am not persuaded that I should adopt their construction, which relies entirely on a passage and a diagram that describe the preferred embodiment of claim l’s LED array. It is a fundamental rule of claim construction that “[rjeferences to a preferred embodiment, such as those often present in a specification, are not claim limitations.” Laitram Corp. v. Cambridge Wire Cloth Co., 863 F.2d 855, 865 (Fed.Cir.1988); see also Ekchian v. Home Depot, Inc., 104 F.3d 1299, 1302-03 (Fed.Cir.1997). Otherwise, “there would be no need for the claims.” SRI Int’l v. Matsushita Elec. Corp. of America, 775 F.2d 1107, 1121 (Fed.Cir.1985). Claim 1 only requires its array to incorporate one component: the LEDs. No additional components are therefore necessary. Except for its description of the preferred embodiment of the array, the specification of the ’645 patent teaches nothing different. Its statement of the invention’s objectives does not mention ballast resistors or claim any functional advantage related to ballast resistors. Perhaps most telling, the preferred embodiment passage relied on by defendants is itself only cursory in its reference to ballast resistors; it does not explain what advantage is to be gained by using them in the array. From the context of the ’645 patent, then, it is clear that the drafter did not intend for the preferred embodiment’s use of ballast resistors to limit the full range of ordinary meaning inherent in the “LED array” phrase’of claim 1. Precision attempts to justify a ballast resistors requirement on functional grounds. As this argument goes, a person of ordinary skill in the art would understand ballast resistors to be necessary components in any voltage-regulated LED array because, without them, a voltage-regulated LED array will not illuminate well in all conditions. From an engineering standpoint, ballast resistors undoubtedly improve the performance of a voltage-regulated LED array. By limiting and spreading the current in the array, they help the LEDs maintain a more even level of illumination. Yet claim 1 recites no limitations on the array’s illumination level, nor does it recite limitations for limiting and spreading current. Because their function is not essential to the claimed array, it follows that ballast resistors themselves are not essential components for that array. Having determined that the “LED array” of claim 1 does not require ballast resistors, the question then becomes whether it also requires a certain configuration of the LEDs. Relume essentially argues that the “LED array” of claim 1 requires a series-parallel configuration of LEDs, but not necessarily the exact series-parallel example of the patent’s preferred embodiment. Defendants argue that this construction improperly imports limitations from the specification into claim 1. They correctly point out the fundamental inconsistency in Relume’s objection to a ballast resistors requirement, which comes from the specification, and its support for a series-parallel requirement, which also comes from the specification. Relume responds by contending that a person of ordinary skill in the art would know that a series-parallel configuration is necessary because LED string redundancy allows the array to continue to emit light in the event of a single point LED failure. I find Relume’s series-parallel construction of “LED array” unpersuasive, however, because it fails to overcome the presumption in favor of the phrase’s ordinary and accustomed meaning. The language of claim 1 does not explicitly limit the “LED array” to a series-parallel configuration. Nor does it implicitly do so. As discussed above, the phrase “LED array” means on its face that the claimed element must arrange LEDs in a regular grouping. A series configuration is simply the logical minimum of this facial meaning and thus cannot be excluded from the phrase’s scope. The specification supports this conclusion. It notes that both series and series-parallel configurations exist in the prior art as design choices for LED arrays. ’645, 1:18-30. If I were to determine that a person of ordinary skill in the art would read a series-parallel limitation into “LED array,” I would violate the fundamental principle that the preferred embodiment not limit the meaning of the claims. See Laitram, 863 F.2d at 865. The specification does not indicate that the drafter acted as his own lexicographer and intended for the series-parallel definition of the preferred embodiment to override the ordinary meaning of “LED array.” See Zebco, 175 F.3d at 990. Aside from the preferred embodiment, there are no explicit series-parallel definitions for claim l’s LED array set forth in the specification. The specification also does not mention a series-parallel configuration in its summary of the invention, nor in its statement of the invention’s objectives. Finally, the specification’s diagrams of the prior art tellingly attach “series-parallel” as an adjective to “LED array”; this further reveals that the phrase “LED array” does not inherently teach a series-parallel configuration to those in the art. Relume falls back on a functionality argument to support its narrow construction. It contends that the LED array of claim 1 requires, at minimum, a series-parallel configuration in order to gain the benefit of LED string redundancy. But. .just as Precision’s function argument failed, so too does Relume’s. Claim 1 nowhere recites a limitation on the configuration of the LED array, nor does it state a functional advantage from a series-parallel configuration. Moreover, claim 1 states no concern for how well or how safely the LED array illuminates, only that it does. All of this makes sense given that the invention described by claim 1 is not a kind of LED array or a safer LED array, but an apparatus that supplies voltage-regulated electrical power to any kind of LED array, whatever its application. I conclude that the intrinsic evidence of record would lead a person of ordinary skill in the art of LED array power supplies to understand the “LED array” of claim 1 to mean an orderly arrangement of LEDs — a meaning that encompasses both a simple series and a series-parallel configuration. I further conclude that a person of ordinary skill in this art would not understand the “LED array” of claim 1 to require ballast resistors. b. “power factor correction converter means” Lumileds argues that 85 U.S.C. § 112, ¶ 6 governs the construction of claim l’s “power factor correction converter means” and limits it in scope to the corresponding structure disclosed in the specification: a switchmode buck/boost converter and a commercially available power factor controller. Relume argues that section 112, paragraph 6 does not apply because the language “power factor correction converter” implicitly recites sufficient structure to one of ordinary skill in the art of LED array power supplies. Claim 1 describes the “power factor correction converter means” as having an input connected to said output of said rectifier means (32) and an output, said power factor correction converter means (38) being responsive to said rectified d.c. power at said power factor correction converter means input for generating regulated voltage d.c. power at said power factor correction converter means output. ’645, 13:22-28. By associating the word “means” with two functions — power factor correction and voltage regulation — claim 1 uses express means-plus-function language to describe the “power factor correction converter means” element. This creates a presumption that the “power factor correction converter means” is a means-plus-function element governed by section 112, paragraph 6. See Al-Site Corp. v. VSI Int'l Inc., 174 F.3d 1308, 1318 (Fed.Cir.1999) (“if the word “means” appears in a claim element in combination with a function, it is presumed to be a' means-plus-function element to which § 112, ¶ 6 applies”). Relume contends that claim 1 overcomes this presumption by reciting sufficient structure. Relume specifically argues that a person of ordinary skill in the art would understand a “power factor correction converter” to be “a switching power supply that has some control feature to improve diode conduction time and increase power factor and reduce distortion.” (Pl.’s Consolidated Opp. at 22.) Relume also notes that the claim language recites a location for the “power factor correction converter means” in the invention — between the rectifier and the LED array — and describes it as having an input and an output. (See id.) The Federal Circuit has determined that a presumption of section 112, paragraph 6 governance “can be rebutted if the evidence intrinsic to the patent and any relevant extrinsic evidence so warrant.” Personalized Media v. Int’l Trade Comm’n, 161 F.3d 696, 704 (Fed.Cir.1998). Throughout the rebuttal inquiry, “the focus remains on whether the claim as properly construed recites sufficiently definite structure to avoid the ambit of § 112, ¶ 6.” Id. A claim recites sufficient structure when it elaborates the structure, material, or acts necessary to perform entirely the recited function. See Sage Products, Inc. v. Devon Industries, Inc., 126 F.3d 1420, 1427-28 (Fed.Cir.1997). Close scrutiny of the term “power factor correction converter means” reveals that it implicitly elaborates sufficient structure to a person of ordinary skill in the art of power supplies. The structural device claimed is a “converter means,” and its functions are “power factor correction” and “being responsive to said rectified d.e. power ... for generating regulated voltage d.c. power.” Although perhaps unremarkable to the layperson, the word “converter” is a structurally meaningful term-of-art to those of ordinary skill in the art of power supply electronics. According to Marty Brown’s Power Supply Cookbook (1994), it connotes the generic structure of a switching power supply: that is, a switch and its controller circuit. See id. at 25-26. The Power Supply Cookbook also makes it clear that power factor correction and voltage regulation are typical functions for a switching power supply to perform. See id. Thus claim l’s association of “converter means” with its specified functions of power factor correction and voltage regulation would reinforce the structural connotations of “converter” to one of ordinary skill in this art. I conclude that the implicitly sufficient level of structural elaboration in the term “converter” removes the “power factor correction converter means” from its presumed statutory category as a means-plus-function element governed by section 112, paragraph 6. See Personalized, 161 F.3d at 705 (holding that the term “detector,” even though it does not “specifically evoke a particular structure,” nevertheless elaborates sufficient structure because it conveys “to one knowledgeable in the art a variety of structures known as ‘detectors’ ”); see also Cole v. Kimberly-Clark Corp., 102 F.3d 524, 531-32 (Fed.Cir.1996) (affirming a district court’s conclusion that the “perforation means” did not fall under section 112, paragraph 6 because the ordinary meaning of the term “perforation” recites sufficient structure to one of ordinary skill in the relevant art). Accordingly, I hold that a person of ordinary skill in the art of LED array power supplies would understand claim l’s “power factor correction converter means” to require the structure of a switching power supply. c. “generating regulated voltage” Defendants argue that the plain meaning of “generating regulated voltage” excludes from the scope of claim 1 those power supplies designed to regulate current. Relume argues that because of the basic electrical principle of Ohm’s Law (voltage = current x resistance) current regulation will result in voltage regulation in a certain circumstance — specifically when resistance is constant. Relume argues that the voltage regulation performed by its invention is limited to that circumstance and, therefore, devices designed to regulate current can fall within the scope of its invention. I begin my claim construction with the ordinary meaning of the disputed phrase. See Phillips, 157 F.3d at 871. The basic meaning of “generate” found in Webster’s is that of a thing producing something else. The meaning of “regulated” is likewise straightforward; Webster’s conveys the idea of something being ordered and controlled. Finally, Webster’s defines “voltage” as “electric potential or potential difference expressed in volts.” By combining these dictionary definitions, it is clear that “generating regúlated voltage” means, on its face, the function of producing controlled electric potential. This function has a specialized understanding to those in the field of electronics. According to The Illustrated Dictionary of Electronics (7th ed.1997), “voltage regulation” is “[t]he stabilization of a voltage against fluctuations in source or load.” Thus, upon reading the words “regulated voltage,” a person of ordinary skill in the art would understand claim 1 to require the “power factor correction converter means” to stabilize the voltage it generates against fluctuations either in the input line voltage (the source) or in the LED array (the load). Yet that is not all the language of claim 1 communicates regarding its voltage regulation function. As held above, the ordinary meaning of “converter” also implies to one of ordinary skill in the art the structure necessary to perform voltage regulation: a switching power supply. At its most basic, a switching power supply must have some sort of switch and a controller circuit. See Power Supply Cookbook at 25-26. For a voltage-regulating power supply, the controller circuit’s “main purpose” must be “to maintain a regulated output voltage.” Id. at 26. It does so by acting as a voltage feedback loop. See id. at 73. These structural limitations implied by the ordinary meaning of “converter” cannot be ignored. Voltage regulation calls for unique componentry — for example, the controller’s output voltage feedback loop. Yet there is an even more important point: a voltage-regulating power supply is a device expressly designed to stabilize the electrical property of voltage and thus generate regulated voltage. It is built to act on voltage, not current. Relume’s tortured construction of “generating regulated voltage” turns a blind eye to these realities. Relume wants claim 1 to be nonsensically construed so that any device, regardless of its design and structure, would fall within its scope so long as that device effects source voltage regulation in the limited circumstance when resistance is constant. I have a duty, however, to give meaning to all the words in claim 1 in order to determine the scope of its claimed invention; the drafter has linked the “converter means” to the “generating regulated voltage” function. Thus I cannot ignore the implicit structural limitations in the term “converter” — structural limitations, I note, that Relume urged me to recognize in order to avoid the application of section 112, paragraph 6 to the “converter means.” There is another flaw in Relume’s construction. The much trumpeted truth of Ohm’s Law is ultimately immaterial to the resolution of the claim construction question before me. All it tells me is that in a certain situation, when resistance is controlled, current-regulating and voltage-regulating power supplies will have the same effect on their output voltage. It does not tell me anything about the purpose, design, and structure of current-regulating and voltage-regulating devices in the art. Thus, while interesting, the scientific fact of Ohm’s Law does not address the underlying issue posed by the construction of “generating regulated voltage”: What does it mean in the art when a converter regulates voltage instead of current? The specification of the ’645 patent reinforces these points. In its discussion of prior art power supplies, it recognizes the distinction drawn in the art between current regulation and voltage regulation. That distinction is based on meaningful engineering reasons. For instance, the specification notes that current regulation will result in better LED light output than voltage regulation. ’645, 4:51-54. The reason: LED light output is directly related to the current flowing through the LED, not the voltage. There is of course a more obvious basis for the distinction in the art: current regulation and voltage regulation act on, and regulate, different electrical properties. Thus it is clear that treating power supplies designed for current regulation like those designed for voltage regulation — the effect of Relume’s construction — would violate precepts in the art. There is nothing in the specification that alters my analysis of “generating regulated voltage.” See Zebco, 175 F.3d at 990. It discloses a voltage-regulating switching power supply for the patent’s invention that is structurally consistent with the ordinary meanings of “converter” and “generating regulated voltage” I discuss above: The converter 38 includes a power factor correction (P.F.C.) integrated circuit (I.C.) controller 40, which is a commercial device available from many sources and functions by allowing current to charge a storage capacitor C (LARGE) only in phase with the rectified a.e. voltage thereby assuring a power factor close to unity. The control I.C. 40 also provides voltage regulation in the switchmode buck/boost converter by monitoring the output voltage and adjusting the high frequency on-off switching period of the pass element eommen-surately. ’645, 5:41-53. Not surprisingly, the specification nowhere instructs the reader on how a current-regulating power supply could be used instead of a voltage-regulating power supply to effect the aims of the invention. For all of the reasons discussed, then, I hold that a person of ordinary skill in the art of LED array power supplies would understand “generating regulated voltage” to mean that claim l’s “converter means” is designed to produce stabilized voltage at its output despite fluctuations in its input voltage. Because the intrinsic evidence of the patent provides a clear meaning for “generating regulated voltage,” I decline to consider the extrinsic testimony of the ’645 patent’s inventor, Mr. Hochstein, which Relume offers in support of its construction. See Southwall Tech., Inc. v. Cardinal IG Co., 54 F.3d 1570, 1578 (Fed.Cir.1995); see also Vitronics, 90 F.3d at 1583. 2. Claim 2 The parties do not dispute the meaning of claim 2. As a dependent claim to claim 1, it incorporates all the Imitations of claim 1, but with one exception. Instead of a generic “converter means,” it teaches the use of a specific type: “a power factor correcting and voltage regulating buck/ boost switchmode converter.” ’645, 13:33-36. 3. Claim 4 The parties do not dispute the meaning of claim 4. Like claim 2, it is a dependent claim to claim 1. It therefore incorporates all the limitations of claim 1 and adds another: the use of an “electromagnetic interference filter means.” ’645, 13:43. It also requires that the filter be located before the rectifier means. ’645, 13:42^16. 4. Claim 5 This claim recites an adaptive clamp circuit means for eliminating leakage current problems. ’645, 13:47-50. Defendants contend that it is written in “means-plus-funetion” format and is. therefore governed by 35 U.S.C. § 112, ¶ 6. Relume does not appear to dispute defendants’ proposed construction. I agree with defendants’ construction. By associating the word “means” with the function of eliminating leakage current problems, claim 5 uses express means-plus-function language to describe its “adaptive clamp circuit means” element. This creates a presumption that the “adaptive clamp circuit means” is a means-plus-function element governed by section 112, paragraph 6. See Al-Site, 174 F.3d at 1318. Unlike the dispute over the “power factor correction converter means,” however, Relume has not argued that claim 5 overcomes this presumption by reciting sufficient structure. Even if Relume were to argue that point, my review of the language of claim 5 does not reveal that it elaborates sufficient structure necessary to perform entirely the recited function. See Sage Products, 126 F.3d at 1427-28. Thus according to section 112, paragraph 6, the “adaptive clamp circuit means” of claim 5 is to be construed “to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.” 35 U.S.C. § 112, ¶ 6; see also Lockwood v. American Airlines, Inc., 107 F.3d 1565, 1570-71 (Fed.Cir.1997). Accordingly, I hold that a person of ordinary skill in the art would understand the corresponding structure described in the specification of the ’645 patent to be a voltage sensing means (48) comprised of a transistor (Ql) and a Zener diode (D5) and a controlled load means (50) comprised of a transistor (Q2) and a resistor (60). ’645, 7:40 to 8:3. The specification explains their operation thus: The clamping circuit 24 works by using the sensing transistor Ql and the Zener diode D5 (the voltage sensing means 48 of FIG. 6a) to determine if the line voltage is below a certain magnitude (typically 40 volts).... If the Zener diode D5 does not conduct, the transistor'Q2 is turned on to place the load resistor 60 [across] the power lines 22 causing the leakage voltage to drop below 10 volts. The transistor Q2 and the resistor 60 are the controlled load means 50 of FIG. 6a. Whenever the traffic signal controller relay “closes”, the line voltage appearing at the input to the adaptive clamping circuit 24 rises to nominally 120 volts and the sensing circuit (Ql and D5) turn off the controlling transistor Q2, removing the resistor 60 from the circuit thereby preventing unnecessary dissipation of power. ’645, 7:53 to 8:1. 5.Claim 6 Claim 6, which depends from claim 5, merely recites the specific structure presented in the specification. Accordingly, claim 6 is similar if not identical in scope to claim 5, in spite of the doctrine of claim differentiation. See Laitram Corp. v. Rexnord, Inc., 939 F.2d 1533, 1538 (Fed.Cir.1991) (finding that the doctrine of “claim differentiation” cannot override section 112, paragraph 6). B. The ’909 Patent Relume’s ’909 patent describes an apparatus, as well as a method, that maintains the luminous intensity of an LED. The patent has 18 claims. Claims 1-3, 6, 7, 9-12, 15, 16, and 18 are at issue in the parties’ motions. They read as follows: 1. A circuit for maintaining the luminous output of a light emitting diode, said circuit comprising: at least one light emitting diode (LED)(12) for producing a luminous output; a sensor (22, 24) for sensing a condition proportional to said luminous output of said LED (12) and for producing a luminous output signal; a power supply (16) electrically connected to said LED (12) for supplying ON/OFF pulses of electrical energy to produce the luminous output of said LED (12); and said power supply (16) including a switching device responsive to said luminous output signal for adjusting the electrical energy supplied by said pulses per unit of time to adjust the average of said current passing through said LED (12) to maintain the luminous output of said LED (12) at a predetermined level. 2. A circuit as set forth in claim 1 wherein said sensor (22) includes means for sensing changes in temperature of said LED (12). 3. A circuit as set forth in claim 2 wherein said sensor (22) includes a predetermined temperature behavior model to establish the increase in said current passing through said LED (12) as a function of the operating temperature of said LED (12) integrated with said predetermined temperature behavior model. ‡ ‡ ‡ ‡ ‡ $ 6. A circuit as set forth in claim 1 wherein said switching device includes means for adjusting the electrical energy supplied by said pulses per unit of time by adjusting the frequency of said pulses. 7. A circuit as set forth in claim 1 wherein said switching device includes means for adjusting the electrical energy supplied by said pulses per unit of time by adjusting the width of said pulses. % í|C íjí ÍJÍ # 9. A circuit as set forth in claim 1 including a filter for filtering the electrical energy supplied by said pulses into substantially d.c. supplied to said LED for producing said luminous output. 10. A method of maintaining the luminous output of a light emitting diode (LED) comprising the steps of: supplying ON/OFF pulses of electrical energy from an adjustable power supply (16) for establishing electrical current passing through the LED (12); sensing (22, 24) a condition proportional to the luminous output of the LED (12); and adjusting the electrical energy supplied by the ON pulses per unit of time to adjust the average of the current passing through the LED (12) to maintain the luminous output of the LED (12) at a predetermined level. 11. A method as set forth in claim 10 wherein sensing a condition is further defined as sensing changes in temperature of the LED (12). 12. A method as set forth in claim 10 further defined as establishing a predetermined temperature behavior model and increasing' the current passing through the LED (12) as a function of the operating temperature of the LED (12) integrated with the predetermined temperature behavior model. ****** 15. A method as set forth in claim 10 further defined as adjusting the electrical energy supplied by said pulses per unit of time by adjusting the frequency of said pulses. 16. A method as set forth in claim 10 further defined as adjusting the electrical energy. supplied by said pulses per unit of time by adjusting the width of said pulses. * * * * * * 18. A method as set forth in claim 10 including filtering the output of the power supply for, filtering the electrical energy supplied by said pulses into substantially d.c. supplied to the LED for producing said luminous output. ’909, 6:64-67, 7:all, and 8:all. 1. Claim 1 a. “condition proportional” Ecolux construes “condition proportional” to mean directly proportional or having “the same or constant ratio.” Ecolux believes this construction requires the invention’s temperature sensor to be located on the LED circuit board, as opposed to somewhere else in the invention’s circuitry. Relume argues that this locational requirement is an unnecessary limitation on the claimed invention. Relume believes that the scope of “condition proportional” includes temperature sensors that are sensitive to the ambient temperature surrounding the LEDs. Claim 1 does not recite a limitation on the location of its sensor. It describes the “sensor” as performing two functions: “sensing a condition proportional to said luminous output of said LED (12) and... producing a luminous output signal.” ’909, 7:1-3. This language limits the possible universe of conditions that could be sensed by the sensor to those that have a “proportional” relationship to the light output of the LEDs. Webster’s most relevant definition of “proportional” is “having the same or a constant ratio;” this is, in fact, Ecolux’s proposed definition. The key to understanding its scope is in the meaning of “ratio.” Webster’s defines it as “the fixed or approximate relation of one thing to another.” Therefore all that claim 1 requires its sensor to do is sense a condition that has a “fixed relation” to the light emitted from.the LEDs; this function does not imply a locational requirement for the invention’s temperature sensor. Despite the fact that the language of claim 1 neither explicitly or implicitly recites a location for the sensor, Ecolux nevertheless argues that such a requirement exists because the preferred embodiment diagram of the temperature sensor depicts it on the LED circuit board. Aside from this diagram, I find no support in the patent’s specification for a locational requirement. Ecolux’s argument is therefore an attempt to restrict claim language that is broader in scope than the preferred embodiment. The rules of claim construction do not permit this. See Electro Med. Sys. S.A. v. Cooper Life Sciences, 34 F.3d 1048, 1054 (Fed.Cir.1994) (“particular embodiments appearing in a specification will not be read into the claims when the. claim language is broader than such embodiments”). Accordingly, I hold that a person of ordinary skill in the art of LEDs would understand “condition proportional” to mean that the sensor must sense a condition that has some fixed relationship with the LEDs’ light output, but would not understand the phrase to require a certain location for the sensor. b. “ON/OFF pulses” On the basis-of some of the invention’s preferred embodiments, Eeolux argues that the “ON/OFF pulses” of electrical energy called for by claim 1 must have a rectangular wave form. Relume contends that the “ON/OFF pulses” limitation does not require a specific wave form but only that the invention’s power supply employ a switching action to control the current delivered to the LEDs. Ecolux’s construction ignores the clear meaning of both the claim language and the specification. Claim 1 recites no limitation on the shape of the pulses’ wave form. Nor does the specification. In fact, it notes that at least two types of wave forms can be utilized by the invention: rectangular and a.c. sinusoidal. Accordingly, I hold that one of ordinary skill in the art of LEDs would understand that “ON/OFF pulses” does not limit the shape of the pulses’ wave form but instead requires that a switching power supply create the pulses by turning a switch on and off. c. “said power supply (16) including a switching device” Relume contends that this phrase requires the switch to be, located in the invention’s power supply. Lumileds disagrees, arguing that the word “including” does not necessarily mean “in.” The ordinary meaning of “including” supports Relume. Webster’s defines it as “serving to enclose or cover.” Reference to the definition of the verb “include” is also helpful, revealing nuances like “to shut up: CONFINE, ENCLOSE, BOUND,” “to place, list, or rate as a part or component of a whole,” and “to take in, enfold, or comprise as a discrete or subordinate part.” These definitions clearly convey the idea that the power supply of the ’909 patent embraces a switch as one of its components.' The specification reflects this.' By repeatedly describing the power supply as including a switch, it emphasizes to one of ordinary skill in the art that the switch is a part of the power supply. But there is a more basic point. By having the power supply include a switch, the intrinsic evidence of the ’909 patent is simply instructing a person of ordinary skill in the art that the power supply of the claimed invention must be a switching power supply. Thus the “including” limitation is less a locational requirement than a componentry requirement. So the specification of the ’909 patent speaks frequently of the invention’s use of “a switch mode power supply.” ’909, .4:66-67. And it claims a great advantage from the inherent efficiency of such a power supply. ’909, 4:50-51. Yet it displays no concern for the location of the switch within the power supply. As the specification states: “It will be appreciated that such a switch mode power supply can take many forms. Within the scope of the present invention, switch mode supplies' include any power source 16 that is turned on and off at a frequency consistent with the other operating parameters of the system.” ’909, 4:66 to 5:3. Accordingly, I hold that a person of ordinary skill in the art would understand “said power supply (16) including a switching device” to mean that the invention of claim 1 requires a switching power supply. d. “maintain ... at a predetermined level” Lumileds argues, that the phrase— “maintain .the luminous output of said LED (12) at a predetermined level” — requires claim l’s switching power supply to adjust the current supplied to the LEDs so that their luminous output is essentially constant. Focusing solely on the meaning of the word “predetermined,” Relume argues that the disputed phrase requires only that the switching power supply maintain LED light intensity at amounts that are known or modeled in advance. The drafter’s use of the word “maintain” exposes the error of Relume’s construction. The idea of uniform or constant output inheres in the word’s ordinary meaning. Webster’s defines “maintain” as “to keep in a state of repair, efficiency, or validity: preserve from failure or decline.” And it defines “predetermine” as “to settle beforehand: settle in advance.” Taken together, these definitions establish that the phrase, “maintain the luminous output of said LED (12) at a predetermined level,” simply means to keep the LEDs’ luminous output at a level chosen beforehand. The specification does not alter this construction. It states that “[t]he present invention relates to a hew method of maintaining an essentially constant luminous output from an LED array, irrespective of operating temperature.” ’909, 4:42-44. It later observes that either of its contemplated sensors — the light sensor or the temperature sensor — “can be used to modulate the average current through the LED array ■ to maintain essentially constant luminous output, irrespective of operating temperature.” ’909, 5:17-20. It also describes how the invention’s preferred embodiment uses a temperature behavior model “in order to keep the luminous output of the LED array essentially constant at a predetermined level.” ’909, 3:66-67. Nowhere does the specification indicate that the invention of the ’909 patent has the ability to produce anything other than essentially constant LED output. In the end, the clear language of claim 1 and the equally clear specification of the ’909 patent demonstrate that Relume’s construction- of “maintain the luminous output of said LED (12) at a predetermined level” is incomplete and at odds with the ordinary meaning of “maintain.” It is not enough, as Relume did in its response brief, to offer a definition for “predetermined” and then ignore the more important and relevant meaning of “maintain.” The disputed phrase must be examined in its entirety in order to comprehend its full scope. Accordingly, I hold that a person of ordinary skill in the art would understand the claim language “maintain the luminous output of the said LED (12) at a predetermined level” to charge the invention of claim 1 with the task of keeping, or preserving from decline, the luminous output of its LEDs at an amount chosen beforehand. 2. Claims 2, 3, 6, 7, and 9 The parties do not dispute the meaning of these claims, all of which depend from claim 1. Claim 2 requires that the “sensor” recited in claim 1 “include[ ] means for sensing changes in temperature of said LED (12).” ’909, 7:13-15. Claim 3 requires that the temperature feedback sys-tern of the ’909 patent use a “predetermined temperature behavior model.” ’909, 7:20-21. Claim 6 specifies that the invention’s switching power supply must adjust its ON/OFF pulses “by adjusting the frequency of said pulses.” ’909, 7:31-32. Claim 7 alternatively teaches a switching power supply that adjusts its ON/OFF pulses “by adjusting the width of said pulses.” ’909, 7:35-36. Finally, claim 9 requires that the invention of claim 1 include a filter for converting the ON/OFF pulses into d.c. power for the LEDs. ’909, 7:41-44. 3. Claim 10 Claim 10 is an independent claim that recites a three-step method for “maintaining the luminous output of a light emitting diode (LED).” ’909, 8:1-2. Dialight and Relume dispute the meaning of a phrase— “adjustable power supply” — in the claim’s first step, which teaches “supplying ON/ OFF pulses of electrical energy from an adjustable power supply (16) for establishing electrical current passing through the LED (12).” ’909, 8:3-5. Dialight argues that the disputed phrase requires the use of a switching power supply that adjusts the frequency or pulse width of its ON/ OFF current pulses in response to feedback from a sensor. Relume asserts that the “adjustable” limitation only requires a power supply that is adjustable in some broad sense, “e.g., as a voltage regulator.” (Pl.’s Consolidated Opp. at 32.) The ordinary meaning of the adjective “adjustable” provides valuable guidance, though it does not resolve the dispute. Webster’s defines the word to mean “capable of being adjusted,” .Thus to label the invention’s power supply as “adjustable” is to say that it is capable of being adjusted. I note that this implies that something acts on the power supply to adjust it. The specification sharpens the reader’s understanding of “adjustable” by detailing how the invention’s power supply is capable of being adjusted. Thus in summarizing the claimed invention, the specification describes the power supply as including “a switching device responsive to the luminous intensity signal for adjusting the electrical energy supplied by the pulses per unit of time to adjust the average of the current passing through the LED to maintain the luminous intensity of the LED at a predetermined level.” ’909, 2:12-17. The specification also later observes that “[t]he primary purpose of the present invention is to increase the average current through the LED array with increasing temperature, by adjusting the pulse width or frequency of LED switch mode power supply.” ’909, 4:62-65. These overarching statements about the invention of the ’909 patent establish that the specification sets forth a specific meaning for “adjustable power supply.” See Zebco, 175 F.3d at 990. Under that meaning, “adjustable” requires the invention’s switching power supply to be'responsive to a luminous intensity signal from a sensor so that the ON/OFF current pulses supplied by the power supply can be adjusted in their frequency or pulse width. In other words, the invention’s power supply must be capable of being adjusted by the feedback from a sensor that measures, either directly or indirectly, the amount of light emitted by the LEDs. For these reasons, I reject Relume’s construction of “adjustable power supply.” Its construction gives' a vague and irrelevant meaning to the phrase that conveniently ignores the specification’s description of the patent’s invention. The intrinsic evidence of the ’909 patent gives full support to Dialight’s construction of the disputed phrase. I therefore hold that a person of ordinary skill in the art would understand the phrase “adjustable power supply” to mean that the invention’s switching power supply must be capable of being adjusted by the luminous intensity signal of a sensor. 4. Claims 11,12,15,16, and 18 The parties do not dispute the meanings of these method claims, all of which depend from claim 10. Each parallels a dependent apparatus claim. For example, claim 11 takes the substance of claim 2 and gives it the nomenclature of a method claim. Likewise, claim 12 parallels claim 3, claim 15 parallels claim 6, claim 16 parallels claim 7, and claim 18 parallels claim 9. V. Comparison with Accused Products I now turn to the second step of the literal infringement analysis: comparing the properly construed claims with the product or process accused of infringement. See Markman, 52 F.3d at 976. Many infringement arguments are now moot in light of my claim construction. I address only those that survive. A. The ’645 Patent 1. Dialight’s Accused Products Relume has accused two Dialight products of literally infringing claim 1 of its ’645 patent: Dialight’s 8" and 12" LED traffic signals. Dialight argues that its products do not literally infringe claim 1 because, inter alia, they lack a required element — they do not generate regulated voltage. Dialight’s supporting evidence consists of a declaration by its expert, Rand Eikel-berger, who is Dialight’s Vice President for Engineering, and circuitry diagrams attached as exhibits to Eikelberger’s declaration. Referring to these diagrams, Eik-elberger states in his declaration that Dia-light’s accused products use “a current regulator circuit,” the output of which is “regulated (i.e., constant total) current.” (Eikelberger Decl. at ¶ 4.) He explains that the regulator uses current sense resistors to provide feedback about its output so that it can change the ON/OFF ratio of its switching and thereby alter the current flowing to the LED array. (See id. at ¶¶ 11-13.) He states that he witnessed tests of Dialight’s accused products, in which some strings of the LED array were purposefully shorted, and saw that the current output of the regulator remained essentially constant despite the short circuits in the array. (See id. at ¶¶ 7-8 & Ex. 2.) And he also points out that the lack of ballast resistors in Dialight’s accused products is further evidence of current regulation because ballast resistors are current controlling devices that are unnecessary, even wasteful, in arrays already supplied current regulated power by a switching power supply. (See id. at ¶¶ 15-18.) Dialight’s evidence satisfies its Rule 56(c) burden of showing that no genuine issue of material fact exists because that evidence establishes that Dialight’s “converter means” is designed to generate stabilized current. See Celotex, 477 U.S. at 323, 106 S.Ct. 2548. In other words, Dia-light has met its burden of showing that its accused products do not generate regulated voltage within the meaning of claim 1 of the ’645 patent. This consequently triggers Relume’s Rule 56(e) burden “to set forth specific facts showing that there is a genuine issue for trial.” Relume lists the following as evidence of Dialight’s voltage regulation: 1) an advertisement and a marketing press release that state that Dialight’s accused products have voltage regu