An acoustic touch apparatus, comprising: a substrate (5, 105, 305) having a first surface (15, 115, 315) and a second surface (10, 110), the first and second surfaces capable of propagating surface acoustic waves, the second surface (10, 110) comprising a touch region and the first and second surfaces coupled via a rounded connecting surface; at least one acoustic wave transducer (35, 135, 335) on the first surface (15, 115, 315); and at least one reflective array (40, 140, 340) on the first surface (15, 115, 315), said transducer (35, 135, 335) capable of transmitting or receiving surface acoustic waves to and from said reflective array (40, 140, 340), said substrate (5, 105, 305) and said reflective array (40, 140, 340) capable of acoustically coupling surface acoustic waves to propagate between the first and second surfaces, and said substrate (5, 105, 305) having a border region on the first surface (15, 115, 315) that is adapted to hide from view through the substrate (5, 105, 305) the transducer (35, 135, 335) and the reflective array (40, 140, 340), said border region is adapted to preclude distortion of surface acoustic waves propagating over a window (156, 356) in the border region, characterized in that the border region comprises a border layer on the first surface (15, 115, 315) and includes an acoustic lens (160, 360) that counteracts a phase shift of surface acoustic waves propagating over the window (156, 356) the window being an uncoated area in the border layer (27, 14'), wherein a height of the acoustic lens (160,360) is specified by the following: y ′ x = Ycorr ⋅ y x where x is a coordinate along the width of the window, where y'(x) is the height along an Y-coordinate of the acoustic lens along direction of propagation of the surface acoustic waves; y(x) is the known height of the window (156, 356) along the Y-coordinate; and Ycorr is a constant, dependent only on the surface acoustic wave velocities of propagation, defined as follows: Ycorr = V 2 / V 0 ⋅ V 0 − V 1 / V 1 − V 2 where V 0 is the surface acoustic wave phase velocity in the window (156, 356); V 1 is the surface acoustic wave phase velocity on the border layer except on the window (156, 356); and V 2 is the surface acoustic wave phase velocity of the acoustic lens on the border layer. a substrate (5, 105, 305) having a first surface (15, 115, 315) and a second surface (10, 110), the first and second surfaces capable of propagating surface acoustic waves, the second surface (10, 110) comprising a touch region and the first and second surfaces coupled via a rounded connecting surface; at least one acoustic wave transducer (35, 135, 335) on the first surface (15, 115, 315); and at least one reflective array (40, 140, 340) on the first surface (15, 115, 315), said transducer (35, 135, 335) capable of transmitting or receiving surface acoustic waves to and from said reflective array (40, 140, 340), said substrate (5, 105, 305) and said reflective array (40, 140, 340) capable of acoustically coupling surface acoustic waves to propagate between the first and second surfaces, and said substrate (5, 105, 305) having a border region on the first surface (15, 115, 315) that is adapted to hide from view through the substrate (5, 105, 305) the transducer (35, 135, 335) and the reflective array (40, 140, 340), said border region is adapted to preclude distortion of surface acoustic waves propagating over a window (156, 356) in the border region, the border region comprises a border layer on the first surface (15, 115, 315) and includes an acoustic lens (160, 360) that counteracts a phase shift of surface acoustic waves propagating over the window (156, 356) the window being an uncoated area in the border layer (27, 14'), wherein a height of the acoustic lens (160,360) is specified by the following: y ′ x = Ycorr ⋅ y x where x is a coordinate along the width of the window, where y'(x) is the height along an Y-coordinate of the acoustic lens along direction of propagation of the surface acoustic waves; y(x) is the known height of the window (156, 356) along the Y-coordinate; and Ycorr is a constant, dependent only on the surface acoustic wave velocities of propagation, defined as follows: Ycorr = V 2 / V 0 ⋅ V 0 − V 1 / V 1 − V 2 where V 0 is the surface acoustic wave phase velocity in the window (156, 356); V 1 is the surface acoustic wave phase velocity on the border layer except on the window (156, 356); and V 2 is the surface acoustic wave phase velocity of the acoustic lens on the border layer. where x is a coordinate along the width of the window, where y'(x) is the height along an Y-coordinate of the acoustic lens along direction of propagation of the surface acoustic waves; y(x) is the known height of the window (156, 356) along the Y-coordinate; and Ycorr is a constant, dependent only on the surface acoustic wave velocities of propagation, defined as follows: Ycorr = V 2 / V 0 ⋅ V 0 − V 1 / V 1 − V 2