BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a partial block diagram of an embodiment 1 of the present invention;
FIG. 2 is a plan view of the embodiment 1 of the present invention;
FIG. 3 is a plan view of an embodiment 2 of the present invention;
FIG. 4 is a plan view of an embodiment 3 of the present invention;
FIG. 5 is a plan view of an embodiment 4 of the present invention;
FIG. 6 is a plan view of an embodiment 5 of the present invention;
FIG. 7 is a plan view of an embodiment 6 of the present invention;
FIG. 8 is an image diagram of a ray transmitted or reflected in the embodiment 1 of the present invention and photographed by an image sensor; and
FIG. 9 is an explanatory graph showing a relation between an electric signal outputted from the embodiment 1 of the present invention and a float.