Surface acoustic wave device
AssigneeMitsubishi Denki Kabushiki Kaisha
InventorsYoshiko Tera, Kouji Morishima, Atsushi Sakai
Life of this patent
Estimating the term…
Abstract
To obtain a surface acoustic wave device which can be produced with ease at a low cost and can be reduced in size without causing deterioration of characteristics, a surface acoustic wave device having input and output transducers arranged alternately on the surface of a substrate for propagating a surface acoustic wave includes metal patterns provided outside the transducers along the extension line of the propagation path of the surface acoustic wave and having at least one surface inclined at an angle .theta. (5.degree.<.theta.<85.degree. or -85.degree.<.theta.<-5.degree.) with respect to the propagation direction of the surface acoustic wave.
Claims22
A surface acoustic wave device comprising a substrate for propagating a surface acoustic wave, input transducers for electric and acoustic conversions which are formed on the surface of said substrate, output transducers for electric and acoustic conversions which are formed on the surface of said substrate and arranged alternately with said input transducers in the propagation direction of the surface acoustic wave, and metal patterns which are located outside both said input transducers and said output transducers along the extension line of the propagation direction of the surface acoustic wave, characterized in that
- each of said metal patterns has an inclined side with respect to the propagation direction of the surface acoustic wave;
- wherein each of said metal patterns has at least one side inclined at an angle of .theta. (5.degree.<.theta.<85.degree. or -85.degree.<.theta.<-5.degree.) with respect to the propagation direction of the surface acoustic wave;
- and
- wherein each of said metal patterns has a first side that the surface acoustic wave propagating from said transducer reaches first and a second side that the surface acoustic wave reaches after passing through an area where said metal pattern is located, both sides being located at the boundary between said metal pattern and said substrate, said first side being perpendicular to the propagation direction of the surface acoustic wave and said second side being inclined.
A surface acoustic wave device comprising a substrate for propagating a surface acoustic wave, input transducers for electric and acoustic conversions which are formed on the surface of said substrate, output transducers for electric and acoustic conversions which are formed on the surface of said substrate and arranged alternately with said input transducers in the direction of the surface acoustic wave, grating reflectors which are located outside both said input transducers and said output transducers along the extension line of the propagation direction of the surface acoustic wave, and metal patterns which are located outside said grating reflectors along the extension line of the propagation direction of the surface acoustic wave, characterized in that
- each of said metal patterns has an inclined side with respect to the propagation direction of the surface acoustic wave.
Dependencies are inferred from the claim text.