Detection device
According to an aspect, a detection device includes: a substrate; a plurality of first electrodes arranged on a first principal surface of the substrate; a plurality of photodiodes provided corresponding to the first electrodes, and each including a first carrier transport layer, an active layer, and a second carrier transport layer; a second electrode provided across the photodiodes; a backlight provided on a second principal surface side opposite to the first principal surface of the substrate; a plurality of light-blocking layers provided between the backlight and the photodiodes; and a light-transmitting area formed between adjacent light-blocking layers of the light-blocking layers.
1. A detection device comprising:
a substrate;
a plurality of first electrodes arranged on a first principal surface of the substrate;
a plurality of photodiodes provided corresponding to the first electrodes, and each comprising a first carrier transport layer, an active layer, and a second carrier transport layer;
a second electrode provided across the photodiodes;
a backlight provided on a second principal surface side opposite to the first principal surface of the substrate;
a plurality of light-blocking layers provided between the backlight and the photodiodes; and
a light-transmitting area formed between adjacent light-blocking layers of the light-blocking layers;
a plurality of gate lines extending in a first direction; and
a plurality of signal lines extending in a second direction,
wherein
a first distance, which is a distance of the light-transmitting area in the second direction between one of the light-blocking layers and one of the gate lines adjacent to the one of the light blocking layers in the second direction, is greater than a half of a distance of the first electrode in the second direction,
a second distance, which is a distance of the light-transmitting area in the first direction between the one of the light-blocking layers and one of the signal lines adjacent to the one of the light blocking layers in the first direction, is greater than a half of a distance of the first electrode in the first direction, and
the light-transmitting area is continuous and L-shaped.
2. The detection device according to claim 1 , wherein, in an area overlapping each of the light-blocking layers, the first electrode, the first carrier transport layer, the active layer, the second carrier transport layer, and the second electrode are stacked in the order as listed, in a direction orthogonal to the first principal surface of the substrate.
3. The detection device according to claim 1 , wherein
the first carrier transport layer of each photodiode is provided so as to cover an upper surface and side surfaces of the first electrode provided for the photodiode,
the active layer of the photodiode is provided so as to cover an upper surface and side surfaces of the first carrier transport layer of the photodiode,
the second carrier transport layer of the photodiode is provided so as to cover an upper surface and side surfaces of the active layer of the photodiode, and
the second electrode is provided so as to cover an upper surface and side surfaces of the second carrier transport layer of the photodiode.
4. The detection device according to claim 1 , further comprising:
a plurality of switching elements provided corresponding to the photodiodes; and
a plurality of gate lines and a plurality of signal lines coupled to the switching elements, wherein
the first carrier transport layer, the active layer, and the second carrier transport layer that form each photodiode are formed individually for each area surrounded by the gate lines and the signal lines.
5. The detection device according to claim 1 , wherein
the first carrier transport layer of each photodiode is provided so as to cover side surfaces of the first electrode provided for the photodiode,
the first carrier transport layer, the active layer, the second carrier transport layer, and the second electrode are stacked to have the same width, and
the detection device further comprises an insulating film that covers side surfaces of each of the first carrier transport layer, the active layer, the second carrier transport layer, and the second electrode.
6. The detection device according to claim 5 , further comprising:
a plurality of switching elements provided corresponding to the photodiodes; and
a plurality of gate lines extending in a first direction and a plurality of signal lines extending in a second direction intersecting the first direction, the gate lines and the signal lines being coupled to the switching elements, wherein
the first electrodes are formed individually for respective areas surrounded by the signal lines and the gate lines,
the first carrier transport layer, the active layer, and the second carrier transport layer are continuously formed over the first electrodes arranged in the second direction, and
the first carrier transport layers, the active layers, and the second carrier transport layers that form photodiodes adjacent in the first direction of the photodiodes are coupled together through a coupling portion provided so as to overlap a corresponding one of the gate lines.
7. The detection device according to claim 1 , further comprising shield wiring provided so as to surround the first electrodes and configured to be supplied with a fixed potential, wherein
the first carrier transport layer, the active layer, and the second carrier transport layer of each photodiode are provided so as to cover the shield wiring and the first electrode provided for the photodiode.
8. The detection device according to claim 7 , wherein
the shield wiring is provided for each of the first electrodes,
the detection device further comprises:
a first coupling line that extends in a first direction and couples together a plurality of pieces of the shield wiring adjacent in the first direction; and
a second coupling line that extends in a second direction intersecting the first direction and couples together a plurality of pieces of the shield wiring adjacent in the second direction, and
a plurality of the first coupling lines and a plurality of the second coupling lines are provided in a grid pattern.
9. The detection device according to claim 7 , wherein
the shield wiring is provided so as to overlap each of the light-blocking layers, and
the shield wiring is disposed inside an outer perimeter of the light-blocking layer in a plan view in a direction orthogonal to the substrate.
10. The detection device according to claim 7 , further comprising a counter electrode that is provided so as to overlap each of the light-blocking layers and is provided between the light-blocking layer and the substrate, wherein
the counter electrode is electrically coupled to the shield wiring.
11. The detection device according to claim 7 , further comprising:
a plurality of switching elements provided corresponding to the photodiodes; and
a plurality of gate lines and a plurality of signal lines coupled to the switching elements, wherein
the first electrodes are formed individually for respective areas surrounded by the signal lines and the gate lines,
the shield wiring is formed individually for each of the areas surrounded by the signal lines and the gate lines, and
the first carrier transport layer, the active layer, and the second carrier transport layer are continuously formed over the first electrodes and a plurality of pieces of the shield wiring.
12. The detection device according to claim 1 , wherein each first electrode, the second electrode, or both are made of a light-transmitting conductive material.
13. The detection device according to claim 1 , wherein each of the first electrodes is formed of a metal material.
14. The detection device according to claim 1 , wherein an area ratio of light receiving portion of each of the photodiodes to the light-transmitting area is in a range from 0.8:1.0 to 1.0:0.8.
15. The detection device according to claim 1 , wherein
either each first electrode or the second electrode is a cathode electrode, and
another of the first electrode and the second electrode is an anode electrode.
16. The detection device according to claim 1 , further comprising a light guide portion provided so as to overlap the photodiodes, wherein
the light guide portion comprises light guide paths, at least some of which overlapping the photodiodes, and comprises a light-blocking portion that has higher optical absorbance than that of the light guide paths.
17. The detection device according to claim 1 , wherein the backlight is a flexible organic light-emitting diode (OLED) light source.