peak portion p 1 is as represented by a curve viii in fig9 b from which it will be understood that the pass band ripples have disappeared fig6 b 6d 7b and 7d illustrate embodiments in which the leading electrode 11a is grounded and fig6 a 6c and 7c illustrate embodiments in which the leader terminal 11b is grounded fig6 a 6d 7a and 7d illustrate constructions by which the induced level in the output terminal 3a fig3 is increased and fig6 b 6c 7b and 7c illustrate constructions by which the induced level in the output terminal 36 fig 3 is increased as mentioned above after determining the positions where the patterns 30 and 31 are to be formed and the desired capacitance value of the coupling between the patterns 30 and 31 an exposure mask not shown for the manufacturing is formed and the filter chip for the product is manufactured by a process such as that illustrated in fig8 a 8b and 8c in the above mentioned embodiments one electrode of the input transducer 2 and one electrode of the output transducer 3 are coupled together but the present invention is not limited to these embodiments for example by combining the embodiments illustrated in fig6 a and 6b that is by coupling both electrodes of the input transducer 2 to the output transducer 3 and by adjusting the coupling capacitances the induced level in the output terminals can be equalized the surface acoustic wave filter device according to a further embodiment of the present invention is discussed below with reference to fig1 this embodiment is different from the afore mentioned embodiment and this embodiment is most suitable for applications such as in fig2 b when the filter.