Acoustic surface-wave velocity transformation

Claim 2

A structure for generating an acoustic surface wave in a nonpiezoelectric substrate comprising: a. a non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a thin piezoelectric layer having substantially uniform thickness formed over a first region on one surface of said substrate, said piezoelectric layer having an axis along which the velocity of surface wave propagation is different from said first velocity, said layer defining a boundary interface with said substrate along said axis, said boundary interface having an effective cross-sectional width which is tapered from a maximum to a point; and c. means for generating an acoustic surface wave in said piezoelectric material and said substrate thereunder that propagates along said axis.

Claim 3

A structure for generating an acoustic surface wave in a non-piezoelectric substrate comprising: a. a non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a thin piezoelectric layer formed over a first region on one surface of said substrate, said piezoelectric layer having an axis along which the velocity of surface wave propagation is greater than said first velocity, a portion of said layer intersecting said axis terminating in a V shaped boundary, the vertex of which is directed along said axis; and c. means on said layer for generating an acoustic surface wave in said piezoelectric layer and said substrate thereunder having a propagation path along said axis, said means disposed adjacent said vertex.

Claim 4

A structure for generating an acoustic surface wave in a non-piezoelectric substrate comprising: a. a non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a thin piezoelectric layer formed over a first region on one surface of said substrate, said piezoelectric layer having an axis along which the velocity of surface wave propagation is greater than said first velocity, a portion of said layer intersecting said axis terminating in a V shaped boundary, the vertex of which is directed along said axis; and c. means on said layer for generating an acoustic surface wave in said piezoelectric layer and said substrate thereunder having a propagation path along said axis, said means disposed adjacent said vertex.

Claim 5

A structure for generating an acoustic surface wave in a non-piezoelectric substrate comprising: a. a non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a thin piezoelectric layer formed over a first region on one surface of said substrate, said piezoelectric layer having an axis along which the velocity of surface wave propagation is less than said first velocity, the side of said layer intersecting said axis terminating in a V shaped boundary, the vertex of which is directed along said axis away from the inner portion of said layer; and c. means for generating an acoustic surface wave in said piezoelectric layer and said substrate thereunder that propagates along said axis.

Claim 6

A structure for generating an acoustic surface wave in a non-piezoelectric substrate comprising: a. a non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a thin piezoelectric layer formed over a first region on one surface of said substrate, said piezoelectric layer having an axis along which the velocity of surface wave propagation is less than said first velocity, the side of said layer intersecting said axis terminating in a V shaped boundary, the vertex of which is directed along said axis away from the inner portion of said layer; and c. means for generating an acoustic surface wave in said piezoelectric layer and said substrate thereunder that propagates along said axis.

Claim 7

A structure for guiding an acoustic surface wave in a non-piezoelectric substrate comprising in combination: a. a substantially isotropic non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a first relatively narrow elongated thin layer of material on said substrate capable of propagating an acoustic surface wave at a second velocity that is slower than said first velocity, said first layer defining a waveguide one end of which is tapered in width; c. a second relatively wide elongated thin layer of piezoelectric material capable of propagating an acoustic surface wave at a velocity intermediate said first and second velocities, one end of said second layer enclosing at least a portion of said tapered end; and d. means for generating an acoustic surface wave in said second layer along a path in alignment with said waveguide.

Claim 8

A structure for guiding an acoustic surface wave in a non-piezoelectric substrate comprising in combination: a. a substantially isotropic non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a first relatively narrow elongated thin layer of material on said substrate capable of propagating an acoustic surface wave at a second velocity that is slower than said first velocity, said first layer defining a waveguide one end of which is tapered in width; c. a second relatively wide elongated thin layer of piezoelectric material capable of propagating an acoustic surface wave at a velocity intermediate said first and second velocities, one end of said second layer enclosing at least a portion of said tapered end; and d. means for generating an acoustic surface wave in said second layer along a path in alignment with said waveguide.

Claim 9

A structure for guiding an acoustic surface wave comprising: a. a piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity along an axis thereof; b. means on said substrate for generating an acoustic surface wave; and c. a relatively thin elongated layer of substantially uniform thickness capable of propagating an acoustic surface wave at a second velocity which is slower than said first velocity positioned along said axis on one surface of said substrate, the end of said elongated layer adjacent said surface wave generating means tapered to a point in cross-section width.

Claim 10

A structure for guiding an acoustic surface wave comprising: a. a piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity along an axis thereof; b. means on said substrate for generating an acoustic surface wave; and c. a relatively thin elongated layer of substantially uniform thickness capable of propagating an acoustic surface wave at a second velocity which is slower than said first velocity positioned along said axis on one surface of said substrate, the end of said elongated layer adjacent said surface wave generating means tapered to a point in cross-section width.

Claim 11

A structure for guiding an acoustic surface wave in a non-piezoelectric substrate comprising in combination: a. a substantially isotropic non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a first relatively narrow elongated thin layer of material on said substrate capable of propagating an acoustic surface wave at a second velocity that is slower than said first velocity, said first layer defining a waveguide, one end of which is tapered in width to a point; c. a second relatively wide elongated thin layer of piezoelectric material capable of propagating an acoustic surface wave along an axis at a velocity intermediate said first and second velocities, one end of said second layer being tapered to a point and spaced opposite from said tapered end of said waveguide along said axis; and d. means for generating an acoustic surface wave in said second layer along said axis.

Claim 12

A structure for guiding an acoustic surface wave in a non-piezoelectric substrate comprising in combination: a. a substantially isotropic non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a first relatively narrow elongated thin layer of material on said substrate capable of propagating an acoustic surface wave at a second velocity that is slower than said first velocity, said first layer defining a waveguide, one end of which is tapered in width to a point; c. a second relatively wide elongated thin layer of piezoelectric material capable of propagating an acoustic surface wave along an axis at a velocity intermediate said first and second velocities, one end of said second layer being tapered to a point and spaced opposite from said tapered end of said waveguide along said axis; and d. means for generating an acoustic surface wave in said second layer along said axis.

Claim 13

A structure for guiding an acoustic surface wave in a non-piezoelectric substrate comprising in combination; a. a substantially isotropic non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a thin layer of piezoelectric material covering one surface of said substrate having an elongated aperture therethrough exposing a region of said substrate, one end of said aperture being tapered in width, said layer having a surface wave propagation velocity which is greater than said first velocity; and c. means for generating an acoustic surface wave in said layer, said means in alignment with the tapered end of said aperture and spaced therefrom.

Claim 14

A structure for guiding an acoustic surface wave in a non-piezoelectric substrate comprising in combination; a. a substantially isotropic non-piezoelectric substrate capable of propagating an acoustic surface wave at a first velocity; b. a thin layer of piezoelectric material covering one surface of said substrate having an elongated aperture therethrough exposing a region of said substrate, one end of said aperture being tapered in width, said layer having a surface wave propagation velocity which is greater than said first velocity; and c. means for generating an acoustic surface wave in said layer, said means in alignment with the tapered end of said aperture and spaced therefrom.

Claim 15

An acoustic surface wave propagating structure comprising a thin layer characterized by a first acoustic surface wave propagating velocity, said layer defined on a substrate characterized by a second different surface wave propagating velocity, said layer disposed on said substrate along the path traversed by an acoustic surface wave, said layer defining a boundary interface with said substrate in said path of propagation, said boundary interface having an effective cross sectional width through which said surface wave propagates which tapers from a maximum to zero, the boundary walls of said tapered portion defined at an angle to said path of propagation such that acoustic surface wave reflection therefrom is substantially reduced upon said surface wave being transformed from propagation at one velocity to propagation at the other velocity.

Claim 16

An acoustic surface wave propagating structure comprising a thin layer characterized by a first acoustic surface wave propagating velocity, said layer defined on a substrate characterized by a second different surface wave propagating velocity, said layer disposed on said substrate along the path traversed by an acoustic surface wave, said layer defining a boundary interface with said substrate in said path of propagation, said boundary interface having an effective cross sectional width through which said surface wave propagates which tapers from a maximum to zero, the boundary walls of said tapered portion defined at an angle to said path of propagation such that acoustic surface wave reflection therefrom is substantially reduced upon said surface wave being transformed from propagation at one velocity to propagation at the other velocity.