Pitney Bowes Inc. v. Hewlett-Packard Co.

• Citation: 51 USPQ2d 1161,182 F.3d 1298
• Decision Date: 23 June 1999
• Docket Number: HEWLETT-PACKARD
• Parties: (Fed. Cir. 1999) PITNEY BOWES, INC., Plaintiff-Appellant, v.COMPANY, Defendant-Cross Appellant. 98-1298, -1347 Decided:
• Court: United States Courts of Appeals. United States Court of Appeals for the Federal Circuit

Page 1298

182 F.3d 1298 (Fed. Cir. 1999)

PITNEY BOWES, INC., Plaintiff-Appellant, v. HEWLETT-PACKARD COMPANY, Defendant-Cross Appellant.

98-1298, -1347

United States Court of Appeals for the Federal Circuit

Decided: June 23, 1999

Appealed from: U.S. District Court for the District of Connecticut, Chief Judge Alfred V. Covello

[Copyrighted Material Omitted]

Michael V. Ciresi, Robins, Kaplan, Miller & Ciresi L.L.P., of Minneapolis, Minnesota, argued for plaintiff-appellant. With him on the brief were Thomas L. Hamlin, Jan M. Conlin, and Katie Crosby Lehmann. Of counsel on the brief was Michael J. Dorney, Tyler, Cooper & Alcorn, of New Haven, Connecticut.

John J. Lauter, Pennie & Edmonds LLP, of New York, New York, argued for defendant-cross appellant. With him on the brief were Jonathan A. Marshall, Edmond R. Bannon, Michael J. Lyons, and Leo Merken. Of counsel was James G. Green, Jr., Pepe & Hazard, of Hartford, Connecticut.

Before MICHEL, PLAGER, and RADER, Circuit Judges.

Opinion for the court filed by Circuit Judge MICHEL, in which PLAGER and RADER, Circuit Judges, join. Additional views filed by Circuit Judge RADER, in which Circuit Judge PLAGER joins.

MICHEL, Circuit Judge.

This appeal arises from a patent infringement action brought by Pitney Bowes, Inc., against Hewlett-Packard Company in the United States District Court for the District of Connecticut. Hewlett-Packard counterclaimed for a declaratory judgment that the patent-in-suit was invalid, unenforceable, and not infringed. Pitney Bowes appeals from the grant of summary judgment of non-infringement to Hewlett-Packard. See Pitney Bowes, Inc. v. Hewlett-Packard Co., No. 3:95CV01764 (AVC) (D. Conn. Mar. 23, 1998) (the "March Non-Infringement Ruling"). Hewlett-Packard cross-appeals from the denial of its two earlier summary judgment motions with respect to non-infringement, based, respectively, upon different claim language and invalidity. See Pitney Bowes, Inc. v. Hewlett-Packard Co., No. 3:95CV01764 (AVC) (D. Conn. Feb. 9, 1998) (the "February Non-Infringement Ruling"); Pitney Bowes, Inc. v. Hewlett-Packard Co., No. 3:95CV01764 (AVC) (D. Conn. Feb. 9, 1998) (the "February Invalidity Ruling"). Our review of the claims, written description and prosecution history of the patent-in-suit leads us to conclude that, in its March Non-Infringement Ruling, the district court incorrectly construed the claim term "spots" to refer to spots of light generated by a laser beam, rather than spots of electrically discharged area on a photoreceptor. Because the grant of summary judgment of non-infringement was derived from the erroneous claim construction, we vacate the March Non-Infringement Ruling and remand for further proceedings in light of the correct claim construction. Because we vacate the grant of summary judgment and remand the case, Hewlett-Packard's cross-appeal from the denials of its two other summary judgment motions, not appealable independently, no longer arises from appealable orders and, therefore, we must dismiss both parts of the cross-appeal without addressing their merits.

BACKGROUND

The patent-in-suit, United States Patent No. 4,386,272 (the "'272 patent"), was issued on May 31, 1983 to Frank T. Cheek, Jr. and Ronald P. Sansome and assigned to Pitney Bowes. The '272 patent is entitled "Apparatus and Method for Generating Images by Producing Light Spots of Different Sizes" and is directed towards the technology of laser printing.

Laser printers, including the accused Hewlett-Packard devices in the instant case, convert electronic information into hard copy representations of images and characters, such as words and numbers. In general, laser printers operate by directing laser light onto a photoreceptor. Specifically, the photoreceptor consists of a drum, the surface of which is evenly covered with an electrical charge. When a beam of laser light strikes the drum, it dissipates a small area of the charge on the drum surface. This discharged area attracts charged toner, which is then transferred from the drum to the paper (by melting the toner particles into the paper fibers), thereby creating the final, permanent image. The photoreceptor drum is then cleaned and recharged so that the process can begin again. Each image (such as a letter or number) is composed of hundreds or thousands of these small dots of toner particles.

As a result of using similarly sized toner dots, the corners and edges of certain characters generated by laser printers can have an uneven appearance. This problem is known in the printing industry as "jaggies." The '272 patent teaches an apparatus and method for combating the problem of jaggies by using toner dots of different sizes. Indeed, the specification of the '272 patent explains that it can be used "to avoid roughened edges and improve character formation." '272 pat., col. 6, ll. 4-5.

Figure 1 of the '272 patent is illustrative of the laser printer apparatus which can be used to create such different sized toner dots:

[Tabular or Graphical Material Omitted]

As explained by reference to the numbering system depicted in Figure 1 of the '272 patent, a light source 10, such as a laser, generates a beam of light 12, which is directed through a neutral density filter 14 to control the light intensity. After passing through the neutral density filter, the light beam passes through several lenses 20, 22 and 24, until it reaches the reflecting face or facet 26 of a rotating polygonal mirror 28. The rotating polygonal mirror reflects multiple light beams 12, which then scan across, rather like a raster, onto a photoreceptor 32 mounted on a spinning drum. Each of these beams of light strikes the photoreceptor at a different location, causing the formation of a small discharged area at that point. As explained above, toner is attracted to each of these discharged areas and the image is then transferred to paper.

The '272 patent teaches two methods for varying toner dot size. First, as illustrated in Figure 1 of the '272 patent, an intensity modulator 64 can be attached to the source of the light beam. The degree of exposure on the photoreceptor is determined by two factors: (1) the intensity of the beam of light; and (2) the length of time that the beam of light remains in contact with the surface of the photoreceptor (which factor is termed the "pulse width"). Thus, as the intensity modulator increases or decreases the intensity of the beam of light, the greater or fewer the number of electrons that will be displaced on the photoreceptor. Because the size of toner dot that is ultimately produced on the paper correlates with the size of exposed area generated on the photoreceptor, the intensity modulator can be used to control toner dot size.

The second method taught by the '272 patent for varying toner dot size is that "[t]he system of this invention can also employ two power sources using parallel laser beams with each of the beams being of a different diameter and corresponding spot size." '272 pat., col. 6, ll. 5-8. Again, because different sized exposed areas are generated on the photoreceptor, this alternative, multiple beam embodiment creates different sized dots of toner on the paper, thereby reducing the problem of jaggies.

The first three claims of the '272 patent are the only claims at issue in this appeal. They claim:

1. A method of producing on a photoreceptor an image of generated shapes made up of spots, comprising:

directing a plurality of beams of light towards a photoreceptor, each beam of light generating a spot on the photoreceptor and controlling a parameter of the light beams to produce spots of different sizes whereby the appearance of smoothed edges are given to the generated shapes.

2. The method of claim 1 wherein the parameter controlled is light beam intensity.

3. Apparatus for producing on a photoreceptor an image of generated shapes made up of spots, comprising:

means for directing a plurality of beams of light toward a photoreceptor to generating [sic] a plurality of spots on the photoreceptor and means for generating spots of different sizes whereby the appearance of smoothed edges are given to the generated shapes.

'272 pat., col. 6, ll. 21-41.

The disclosure contained in the specification of the '272 patent also formed the disclosure used in the specification of two additional patents. The '272 patent stems from a parent application filed in July 1978. United States Patent No. 4,214,157 (the "'157 patent") also issued from that application and claims an invention for correcting imperfections in the polygonal mirror during the scanning process. A divisional application, filed from the same parent application, issued as United States Patent No. 4,310,757 (the "'757 patent") and claims an invention for correcting the scanning speed during the scanning process. The '272 patent resulted from a continuation application filed in connection with the application which issued as the '757 patent. A continuation-in-part application was also filed in connection with the '757 patent, which subsequently issued as United States Patent No. 4,809,021 (the "'021 patent"). The '021 patent claims an apparatus and method for smoothing the edges of laser printed characters by using toner dots of three different sizes. The description of the preferred embodiment contained in the specification of the '272 patent is apparently identical, or virtually identical, to that contained in the specifications of the '157 and the '757 patents.

On August 23, 1995, Pitney Bowes filed a complaint in the District of Connecticut alleging infringement of the '272 patent by Hewlett-Packard. In particular, Pitney Bowes contended that claims 1, 2 and 3 of the '272 patent were infringed by laser printers "manufactured, used and/or sold" by Hewlett-Packard. Complaint, 5 (Aug. 23, 1995). The accused devices are laser printers, which all incorporate Hewlett-Packard's "Resolution Enhancement technology" or "REt"...