signal lines 11 and 12 is formed on the substrate 1 which is disposed on the front side the other is formed on the substrate 2 in general the signal lines formed on the substrate 2 are made of a plurality of strips of transparent conductive film which are provided perpendicularly to the signal lines formed on the substrate 1 with the liquid crystal layer 3 interposed therebetween each strip of transparent conductive film also functions as a counter electrode therefore in this case it is unnecessary to additionally provide a counter electrode on the substrate 2 moreover the reduction ofthe specific resistance of the signal line used for information input output can attain the same effects as those attained in the case where an active element having a mobility of 5 cm 2 v s or more is used in the above example the display circuit and the information input output circuit are formed as is shown in fig2 alternatively it is possible toform them as shown in fig4 in fig4 the pixel electrodes 14 are formedon the scanning signal lines 11 and the data signal lines 12 of the displaycircuit and on the signal lines 15 and 16 of the information input output circuit the electrodes 18 of the information input output circuit is formed on the scanning signal lines 11 and the signal lines 15 and 16 in.