Fingerprint detection device and display device

1. A fingerprint detection device comprising:

a substrate;

a plurality of drive electrodes provided on one face side of the substrate and arranged in a first direction; and

a plurality of zigzag detection electrodes provided on the one face side and arranged in a second direction crossing the first direction,

the detection electrodes having:

a plurality of first line parts;

a plurality of second line parts extending in a direction crossing the first line parts; and

bent parts coupling the first line parts and the second line parts to each other, and the drive electrodes having:

a plurality of electrodes arranged spaced apart from each other in a plan view;

connecting parts coupling the electrodes adjacent to each other in the second direction to each other; and

dummy electrodes in a floating state, each of the dummy electrodes being arranged between the two electrodes arranged in the first direction between the two detection electrodes.

2. The fingerprint detection device according to claim 1 , wherein

the electrodes have a shape including two parallel sides, and

sides of the dummy electrodes facing the electrodes are parallel to the sides of the electrodes.

3. The fingerprint detection device according to claim 1 , wherein a width given by extending a center line between a side of the electrode and a side of the dummy electrode facing the electrode along the side of the electrode and causing the center line to reach any of the electrodes, the dummy electrodes, and the connecting parts is larger than one time an arrangement spacing of the two bent parts in the second direction and smaller than three times the arrangement spacing.

4. The fingerprint detection device according to claim 1 , wherein a center line between a side of the electrode and a side of the dummy electrode facing the electrode is extended along the side of the electrode, and an angle formed by the center line and the detection electrode is 90 degrees.

5. The fingerprint detection device according to claim 1 , wherein the electrodes each include:

a first electrode; and

a second electrode different in shape from the first electrode in a plan view.

6. The fingerprint detection device according to claim 5 , wherein

a shape of the first electrode in a plan view is a parallelogram having two sides parallel to a direction in which the first line parts extend, and

a shape of the second electrode in a plan view is a parallelogram having two sides parallel to a direction in which the second line parts extend and different in shape from the first electrode.

7. The fingerprint detection device according to claim 1 , wherein

the electrodes are translucent electrodes, and

the detection electrodes are metallic thin lines.

8. The fingerprint detection device according to claim 1 , wherein a ratio of an arrangement spacing of the bent parts to an arrangement spacing of the drive electrodes is 2 or less in the first direction.

9. The fingerprint detection device according to claim 1 , wherein the connecting parts are alternately arranged on one side and another side of a virtual line passing through an areal gravity center of the electrodes in the second direction.

10. A display device comprising:

a display panel; and

the fingerprint detection device according to claim 1 arranged facing the display panel.