Appeal No. 1997-4033 Application No. 08/589,584 claims, under 35 U.S.C. § 103. We reverse and enter a new2 ground of rejection under 35 U.S.C. § 112. The invention The invention is an improved Mach-Zehnder optical modulator, which is depicted in appellant's Figure 1. A single input is branched by a Y-shaped branching structure in the first passive region 121, whereafter the light is conveyed along two parallel straight phase modulator sections in the active region 122, which sections are rejoined by a second Y- shaped branching structure in the second passive region 123 (Brief at 2). Application of a driving voltage to one or both electrodes 110a and 110b overlying the parallel modulator sections in the active region allows controlled variation of the refractive index of the waveguide material (id.). The Brief further explains (at 2): The present invention seeks to achieve the conflicting objects of minimizing the driving voltage which must be applied to the electrodes in the active region, while also minimizing light propagation loss from the wave-guide (see, for example, page 6, lines 10-15 [of the specification]). That is, the necessary driving 2The new ground of rejection of claims 22-26 under 35 U.S.C. § 112 entered in the Answer (paper No. 23) was withdrawn in paper No. 25, mailed August 20, 1997. 2Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 NextLast modified: November 3, 2007