Gary E. Rhine appeals the judgment of the United States District Court for the Northern District of Ohio, Case No. 96CV7524, which granted Casio, Inc. and Casio Computer Co., Ltd. (collectively “Casio”) summary judgment of nonin-fringemеnt. Because the court improperly construed the claim, we reverse the judgment and remand the case.
*1344 Background
Rhine owns U.S. Patent No. 4,910,652, which is directed to a wrist watch containing a flashlight having a time delay circuit. The time delay circuit turns the flashlight off after a set period of time. The only asserted claim, claim 1, recites: “A time keeping and displaying wrist mountable watch having a flashlight mounted in the case thereof, said flashlight comprising a power supply for supplying electrical power to said flashlight, said power supply electrically connected to at least one light source, and time delay means for automatically extinguishing said light source after a time delay following the energization of said light source by the electrical deenergi-zation of said light source.” Because Casio sells and/or manufactures a wrist watch whose face illuminates with sufficient brightness to light up an area beyond the watch face itself, Rhine sued it for infringement of claim 1.
Following an initial settlement conference, the court ordered Rhine to file a motion to construe the claim, purporting to follow the procedure suggested by
Markman v. Westview Instruments, Inc.,
“Because of th[e] limiting prior art,” the court construed claim 1 “as covering a flashlight that is distinct from the light source thаt illuminates the face of the watch, in combination with a time delay device that automatically extinguishes the flashlight.” ■ This limiting prior art includes a Japanese reference, which disclosеs “a wristwatch having an illumination lamp for lighting a time display unit and for providing illumination outside of the casing.” In addition, the Patent and Trademark Office noted during prosecution that “both mounting search lights and flashlights on a user’s wrist and enabling users to check the time by means of watch dial illumination were known in the prior art, although not in combination.” The court reasoned that, because the Jaрanese reference discloses a single illumination source capable of illuminating both the watch face and an area surrounding the watch face, the flashlight limitation of claim 1 could not be construed to cover this type of single light source.
The court denied Casio’s motion for summary judgment of invalidity, however, because there are genuine issues of material fаct about whether the claim, as construed, is obvious over the prior art. Casio then filed a motion for summary judgment of noninfringement, arguing that its light source was not distinct from the one illuminating the watch face. Based on its claim construction and the undisputed evidence about the accused product’s design and operation, the court granted Casio summary judgment of non-infringement. This appeal followed.
Discussion
We review a district court’s decision to grant summary judgment
de novo. See Gasser Chair Co. v. Infanti Chair Mfg.
*1345
Corp.,
In construing claim 1, the district court ostensibly applied the familiar axiom that “[cjlaims should be so construed, if possible, as to sustain their validity.”
Carman Indus., Inc. v. Wahl,
We, too, have consistently employed the caveat, “if possible,” to our instruction that claims should be construed to sustain their validity.
See, e.g., Whittaker Corp. v. UNR Indus., Inc.,
In the case before us, the court misapplied the аxiom and adopted a construction of “flashlight” that is at odds with the clear language of the claim and the written description. In holding that the recited “flashlight ... is distinct from the light source that illuminates thе face of the watch,” the court construed the claim to require at least
two
light sources — one that illuminates an area beyond the watch face and one that illuminates only the wаtch face (a face illuminator). However, claim 1 recites a flashlight comprising “at least
one
light source.” (Emphasis added). Use of the phrase “at least one” means that there could be only one or more than one.
See Kistler Instrumente AG. v. United States,
*1346 To give meaning to the phrase “at least one light source,” we must construe claim 1 to cover a device that has only one light source or a device that has more than one light source, assuming that the “device” is a “flashlight,” as that tеrm is used in the claim. According to the written description, the flashlight 8 is a light that is bright enough “to illuminate a small room or to otherwise serve satisfactorily as a flashlight.” Col. 2, 11. 46-53. The face illumi-nator 9, in contrаst, is a light that “enable[s] reading the time without turning on [the flashlight] 8 if desired.” Col. 2,11. 58-62. According to the written description, the flashlight 8 and the face illuminator 9 are different elements. However, the written description further explains that light from the flashlight 8 can be used to illuminate the watch face 4 in the absence of a distinct face illuminator. See col. 2,11. 49-54 (“[T]he brightness of lamps 8 and the disposition of lamps 8 abоut case 3 should be arranged to illuminate timepiece face 4 so that the watch hands can be seen in the absence of otherwise provided light and so that the time indicative numbers and dots are also then visible.”). Therefore, properly construed, the flashlight limitation is met by a wrist watch whose only light source illuminates both the watch face and a' significant area beyоnd the watch face. This definition is consistent with the term’s ordinary meaning. See American Heritage Dictionary 511 (2d College ed.1982) (defining “flashlight” as a “small, portable lamp usually powered by batteries”).
Casiо argues that the claim cannot cover a watch without a separate face illuminator because the preferred embodiment includes one. However, “particular embodiments appearing in a specification will not be read into the claims when the claim language is broader than such embodiments.”
Electro Med. Sys. S.A. v. Cooper Life Sciences,
Casio also argues that, under our construction, claim 1 is invalid'because the recited combination is obvious. This argument is premature. Casio cannot avoid a full-blown validity analysis by raising the specter of invalidity during the claim construction phase. Although the court appeared to believe that sevеral pieces of prior art, when viewed in combination, disclose all the limitations of claim 1, it did not conduct a validity analysis.
See Graham v. John Deere Co.,
Conclusion
Accordingly, the judgment of United States District Court for the Northern District of Ohio is reversed and the case is remanded for further proceedings consistent with this opinion.
REVERSED AND REMANDED
