Opinion ID: 785735
Heading Depth: 3
Heading Rank: 1

Heading: A laser system for eroding a surface, said laser system comprising:

Text: 7 laser means for generating pulses of laser light along a beam path at an energy level, such that the pulses can be absorbed at a surface to induce photoablation; 8 support means for aligning a surface relative to the laser means; and 9 beam dimension control means disposed along said laser beam path, including optical means for optically varying an area on the surface to which the pulses of laser energy are delivered while maintaining a substantially constant energy per unit area during each pulse. 10 Marshall '093 patent, col. 24, ll. 15-29 (emphasis added). The other two independent claims, claims 15 and 25, are method claims with similar limitations. The limitations of claims 15 and 25 corresponding to the beam dimension control means of claim 1 are nearly identical and not separately discussed by the parties. 11 In construing the disputed beam dimension control means limitation as a means-plus-function limitation subject to 35 U.S.C. § 112, ¶ 6, the district court stated: 12 The function of this limitation is, using optical component(s) in the path of the laser beam, to vary an area on the surface to which pulses from the laser are delivered but, at the same time, to have each pulse delivered to the surface have substantially the same energy per unit area. Pulses delivered to the surface have substantially the same energy per unit area if they each ablate approximately the same depth of material. There are a number of beam dimension control and optical means described in the patent which perform or assist in performing this function ... including a variable aperture iris diaphragm. 13 Summit Tech., Inc. v. Nidek Co., No. 98-CV-12611-EFH, slip op. at 2 (D.Mass. June 25, 2002) ( Claim Construction Order ). 14 The Azema '330 patent issued on November 27, 1990, and was later acquired by Summit. Of the asserted claims of the Azema '330 patent found to be infringed, only claim 21 is independent. Claim 21 recites, with the disputed term underlined: 15 21. A surgical apparatus useful in performing in situ ophthalmological operations to optimize the curvature of the anterior surface of an area of the cornea of an eye, having an optical axis comprising: 16 (a) a light source having a wavelength in the ultraviolet range, said light source being capable of effecting photochemical decomposition of corneal material; 17 (b) means for selecting out of the light produced by said light source, a portion of light which is essentially unidirectional in nature, whereby a beam of light having an outer portion and a center is formed; 18 (c) means for focusing said beam of light onto the anterior surface of a patient's cornea, whereby a light spot having an area a configuration [sic] is formed, the area of said light spot having a maximum area at least as large as the area of the cornea desired to be operated upon, whereby within the area of the corneal surface impinged by said light spot, ablation of a portion of the corneal material occurs by means of photochemical decomposition, said ablation being time-dependent, whereby, the longer a particular portion of the cornea surface is impinged by said light spot the greater the amount of corneal material ablated; and, 19 (d) means for changing the configuration of said light spot, whereby size or shape of said light spot may be varied or a portion of said light spot may be obscured such that, as a function of time, varying portions of the cornea surface may be made to receive varying amounts of total photoradiant energy, whereby a lenticular lamina of cornea material having a smooth anterior surface may be removed by ablation, thereby locally adjusting the radius of curvature of the cornea surface. 20 Azema '330 patent, col. 11, ll. 14-51 (emphasis added). 21 In construing the disputed means for focusing limitation of the Azema '330 patent as a means-plus-function limitation subject to 35 U.S.C. § 112, ¶ 6, the district court stated: 22 The function of this limitation is to focus the beam to direct a spot of light onto the front surface of the cornea. The area of the spot is at least as large as the area of the cornea one wishes to operate upon. The means structure described in the patent specification for performing this function is a lens. 23 Claim Construction Order, slip op. at 4.