JPS6332305A - Optical position detecting element - Google Patents

Abstract

PURPOSE:To realize a detecting element of simple structure by forming resistance layers, at least one of which is made of a transparent resistance layer, on the top and reverse surfaces of an amorphous Si intrinsic semiconductor layer, and providing the respective resistance layers with electrodes. CONSTITUTION:A reverse surface transparent resistance layer 3 is formed on a substrate 1 made of glass, the amorphous Si intrinsic semiconductor layer 13 is formed thereupon, and a top surface transparent resistance layer 7 is formed further thereupon. Furthermore,electrodes 11a and 11b, and 9a and 9b are formed on the layers 7 and 3. When spot light is incident on the layer 7 at a point B, the film 13 decreases in electric resistance to increase electric conductivity, so a short-circuit state is entered on a perpendicular axis where the layers 7 and 3 contain the point B. The point where the perpendicular axis penetrates the layer 3 is denoted as C. Consequently, currents Ix1 and Ix2 flow on the layer 7 from the electrodes 11a and 11b to the point B and currents Iy1 and Iy2 flow out on the layer 3 from the point C to the electrodes 9a and 9b. For the purpose, those current values are measured to detect the (x) and (y) coordinates of the point B.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an optical position detection element.

(Prior Art) As a conventional input optical position detection element, there is one shown in FIG. 4, for example. As shown in the figure, this optical position detection element has a transparent resistance layer 3 on a substrate 1 made of glass.
A pin-type solar cell 5 is formed thereon, a transparent resistance layer 7 is formed thereon, and a metal electrode 9.11 made of aluminum is further formed on the transparent resistance layers 3 and 7.

(Problems to be Solved by the Invention) However, such an optical position detection element has a pin type solar cell 5, and this pin type solar cell 5 has a three-layer structure having a p layer and an n layer inside. Therefore, there are problems in that the structure is complicated and it takes time to manufacture.

The present invention has been made in view of these problems, and its purpose is to provide an optical position detection element with a simple structure.

(Means for Solving the Problems) In order to achieve the above object, the present invention forms resistive layers, at least one of which is a transparent resistive layer, on the upper and lower surfaces of an amorphous silicon intrinsic semiconductor film. They are characterized by having electrical and electrical connections.

(Function) This optical position detecting element has an amorphous silicon intrinsic semiconductor film formed between two resistors 1, and since this amorphous silicon intrinsic semiconductor film is one layer, the structure of this optical position detecting element is simple.

(Example) Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 1 shows the process of forming the optical position detecting element according to this embodiment, and shows a plan view of the optical position detecting element during formation. As shown in FIG. 1(a), a lower transparent resistance layer 3 is formed on a substrate 1 made of glass. Next, as shown in FIG. 1(b), an amorphous silicon intrinsic semiconductor film 13 is formed on this.
form.

Next, as shown in FIG. 1(C), a top transparent resistance layer 7 is formed. Furthermore, as shown in FIG. 1(d), electrodes 11a, 11b, 9 are provided on the upper transparent resistance layer 7 and the lower transparent resistance layer 3, respectively.
a, form 9b.

FIG. 2 is a cross-sectional view taken along line AA in FIG. 1(d) of this optical position detection element. In this way, the optical position detection element according to this example is formed.

Therefore, according to this embodiment, it is only necessary to form one layer of amorphous silicon intrinsic semiconductor film 13 between the lower transparent resistance layer 3 and the upper transparent resistance layer 7, and instead of forming three layers of PI as in the conventional case.
Since an n-type solar cell is no longer used, the structure of the optical position detection element can be simplified and manufacturing time etc. can be shortened.

FIG. 3 shows the principle of light spot detection using this optical position detection element. For simplicity, the top transparent resistance layer 7. Amorphous silicon intrinsic semiconductor film 13. The lower transparent resistance layer 3 is integrated. Equal positive voltages are applied to the electrodes 11a and 11b of the upper transparent resistance layer 7, and equal negative voltages are applied to the electrodes 9a and 9b of the lower transparent resistance layer 3, or they are grounded.

When the spot light is incident on point B of the upper transparent resistance layer 7, the electrical resistance of the amorphous silicon intrinsic semiconductor film 13 decreases and the electrical conductivity increases, so that the upper surface resistance layer 7 and the lower surface transparent resistance layer 3 are aligned on the vertical axis including point B. becomes a short circuit. This vertical axis marks the lower transparent resistive layer as a point C.

As a result, a current 11 flows from the electrodes 11a and 11b toward the point A on the upper transparent resistance layer 7, and a current II flows from the point C on the lower transparent resistance layer 3 toward the electrodes 9a and 9b. It starts to flow.

The ratio of V1'V2 current II is x1° x from electrodes 11a and 11b
2. Since it is the inverse ratio of the resistance values up to point B, the following equation holds true.

I x1/I x2=j/k,...
- (1) However, I represents the distance from the electrodes 11a and '11b to the point. Similarly, the following equation holds true on the lower transparent resistance layer 3.

1.1/I, 2=n/m ---
(2) However, m and n represent the distance from the electrodes 9a and 9b to the point C.

Therefore, according to equations (1) and (2), the current II! I
xl.

I x2. By measuring yl, 'y2, the X and y coordinates of point B are detected. This is because +j is known and m+n is also known.

Note that if there is no need to transmit the incident light, only the resistive layer serving as the incident surface may be a transparent resistive layer.

[Effects of the Invention] As described in detail above, according to the present invention, the structure of the optical position detection element can be simplified, and manufacturing time and manufacturing costs can be reduced.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the manufacturing process of the optical position detecting element according to this embodiment, and is a plan view of the optical position detecting element in each step. FIG. 2 is a sectional view of this optical position detecting element, FIG. 3 is a principle diagram of light spot detection, and FIG. 4 is a sectional view of a conventional optical position detecting element. 3... Lower surface transparent resistance layer, 7... Upper surface transparent resistance layer, 9
a, 9b, 11 a, 1 lb--electrode, 13...
・Amorphous silicon intrinsic semiconductor device Figure 1 1fh Figure 2 Figure 4

Claims (1)

[Claims] 1. An optical position detection element, characterized in that a resistance layer, at least one of which is a transparent resistance layer, is formed on the upper and lower surfaces of an amorphous silicon intrinsic semiconductor film, and an electrode is provided on each of the two resistance layers.