JPS5932830B2 - Line shape direction detection eye - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an element that optically detects the direction of a line pattern.

Conventionally, when reading a line figure drawn on a drawing using a computer, etc., there is a method in which a part of the figure is read using a two-dimensional array of photoelectric conversion elements as an input device and processed programmatically. Are known.

In fact, such processing must be performed in the case of complex figures, but there are also cases where the target figure has regularity and it is only necessary to know in which direction a straight line passes through a given position. be. For example, design drawings for electronic circuits, etc.
If the drawing is written on graph paper and only allows drawing of wiring in two directions (vertical and horizontal), when reading the drawing,
All you need to know is whether there are vertical or horizontal lines on the grid points of the graph paper. Even in such a case, if the above-mentioned programmatic processing method is used, it will take a non-negligible amount of time on a conventional computer. An object of the present invention is to provide a line pattern direction detecting eye that instantly detects lines in one direction.

Another object of the present invention is to provide a line figure detection eye that can omit the process of detecting the direction of line figures using a computer or the like. FIG. 1 shows the configuration of the present invention.

The direction detecting eye 10 has a planar configuration. One end of the group of rectangular photoelectric conversion elements 1 is grounded, and the other end is connected to a power source via a resistor 2. An output line 3 is drawn out from the connection point between each photoelectric conversion element 1 and the resistor 2,
A direction detecting section 4 detects a line in a certain direction (vertical direction in the form shown in FIG. 1), and outputs it to a detection signal line 5.
By adopting such a configuration, when a line figure parallel to the photoelectric conversion element 1 is projected as shown in FIG. 1, the output line connected to the photoelectric conversion element 1 covered by the line image 25 is 3 and the output voltage value of the output line 3 connected to the unobscured photoelectric conversion element 1 of the line image 25.

Utilizing this, it is possible to detect the existence of a line figure parallel to the photoelectric conversion element 1, that is, the presence of the line figure and its direction. Furthermore, by scanning the present invention over a drawing or the like where it is necessary to determine the direction of a line figure, it is possible to determine whether the line figure is oriented in a certain predetermined direction. Furthermore, by preparing a plurality of photoelectric conversion elements 1 of the present invention with different directions, or by scanning by rotating the direction of one element 1 of the present invention, each of the line figures drawn on a drawing etc. You can get the direction at the position. Next, the principle of the present invention will be explained with reference to FIGS. 1 and 2. A line figure 22 is drawn on a screen 21, which is illuminated by an illumination lamp 23, and whose image 25 is projected by a lens system 24 onto a direction detecting eye 10 on a surface. This line image 25 reduces the amount of light irradiated onto the diagonally shaded portion of the photoelectric conversion element 1 as shown in FIG. Figure 3a is a graph of the current values flowing through each of the ten photoelectric conversion elements 1 (in this example) at this time, and Figure 3b is a graph of the current values flowing through each of the ten photoelectric conversion elements 1 at this time (in this example).
is a graph of the voltage value of the output line 3. At this time, a photoconductor is used as the photoelectric conversion element. That is, the resistance value of the portion irradiated with light decreases. As can be seen, the output voltage of each element exhibits a particularly large value only when a vertical line image exists, and a large difference occurs between the outputs of each element. FIG. 3c shows the output voltage when a horizontal line image is projected onto the detection eye. In this case, since all elements project the line image portion in the same way, no element exhibits a particularly large value, and there is no large difference between the outputs of each element. As can be seen from the above, the magnitude of the output depends on the area occupied by the line image of each photoelectric conversion element. Therefore, by using a rectangular photoelectric conversion element that is sufficiently longer than the thickness of the line figure on the screen and sufficiently narrower than the thickness of the line figure, the direction of the line figure can be sensitively reflected in the output voltage. . Furthermore, when such an element is used, it has the advantage of being resistant to noise. In general, even if vertical straight lines are drawn in drawings, if you look closely, there are often gaps or cuts inside as shown in Figure 5, which shows that the image is continuous from top to bottom without any gaps. If detection is performed as a premise, the stability of detection will be poor. In contrast, in the present invention,
A "vertical straight line" only assumes that the black parts are lined up vertically with sufficient density, so it is hardly affected by small gaps or cuts. The direction detection unit 4 detects from the signal of the output line 3 that ``If a line in a certain direction exists, an output voltage of a particularly large value will appear'' and if a line in a certain direction exists, a large difference will occur between the outputs of each element. ] The detection signal is output to the signal line 5 by utilizing the characteristics. FIG. 4 shows an embodiment of the direction detection section 4.

Each of the output line groups 3 is connected to a Schmitt trigger 41, and the output of the Schmitt trigger is shown in Fig. 3B and c.
It is adjusted so that when a voltage higher than t appears in human power, when it is lower than HighVt, it is 10Wt. Then, the output corresponding to FIG. 3b becomes as shown in FIG. 3d. The output of each Schmitt trigger 41 is connected to the 0R date 42, and if any one becomes 'High', the output of the 0R gate, that is, the detection signal becomes High2 and is output to the signal line 5. The detection method can theoretically work even if there is only one photoelectric conversion element, but in that case, accuracy is required to actually align the drawing with the detection eye.According to the present invention, the line In the case of the image 25 shown in Figs. 1 and 2, stable detection is performed even if the image 25 is slightly shifted left and right.
A second embodiment of the direction detection section 4 is shown in the figure.

Here, 43 is an exclusive OR circuit which outputs a high potential 2 signal only when one of the outputs of the adjacent Schmitt triggers 41 is a high potential and the other is a low potential 2. In this example, the output of OR gate 42 corresponds to the detection of an edge of the line image. The output of the exclusive OR circuit 43 corresponding to FIG. 3d is as shown in FIG. 3e. As shown in FIG. 3b, the present invention can be achieved by detecting only the output of a turn from low potential 2 to high potential 7 and back to low potential 2 when viewed from the left output. Greater than array 1 range. The direction detecting section 4 which does not detect the black-filled portion as the red line 2 can also be configured in a simple manner using the prior art. Furthermore, when the number of elements increases, it is also possible to perform similar processing by scanning the output signal with a multiplexer without placing a Schmitt trigger in parallel as described above.
However, in this case, it takes some extra time. In the above example, the output signal is first digitized by a Schmidt trigger, and post-processing is done by a logic circuit, but as in the second example, when detecting the difference between the outputs of adjacent elements, It is also possible to receive the signals from two adjacent output lines analogously with a differential amplifier and use the output. Next, with reference to FIGS. 7 and 8, the operation of a drawing reading apparatus that uses the present invention to detect the direction of line figures and read drawings will be described.

In the example shown in FIG. 7, a line figure 6 is drawn on a grid with intervals of a, and only two directions of the lines, vertical and horizontal, are allowed. That is, the figure is composed only of lines passing through the lattice points indicated by the O mark 7 in the vertical or horizontal direction. FIG. 8 shows an example of scanning of the direction detecting eye of the present invention for reading such a drawing. In FIG. 8, the mark 8, which is a square with a horizontal bar, indicates the direction of the photoelectric conversion element 1 of the present invention in the left-right direction, and is, for example, a position where scanning is performed in the horizontal direction. Marks 9 marked with ``mark'' indicate that the direction of the photoelectric conversion element 1 of the present invention is the vertical direction, and are, for example, positions where scanning is performed in the lateral direction. In this case, the direction of the direction detecting eye may be rotated alternately between the position of mark 8 and the position of mark 9, or the two direction detecting eyes may be arranged at right angles to each other to determine the position of mark 8 and mark 9. They may be switched or scanned simultaneously. By examining the connections between each grid point 7 according to the present invention in this way, the line figure on the drawing can be read as a set of connections between the grid points. The information read is stable and highly accurate due to the nature of the invention. As described above, by using the present invention, a line in a desired direction can be detected instantaneously.

Since no computer processing is required for direction detection, an inexpensive and high-speed linear direction detector can be constructed.

[Brief explanation of drawings]

Fig. 1 is a configuration diagram of the present invention, Fig. 2 is an explanatory diagram of how to use the present invention, Fig. 3 a to e are graphs of signals of each part of the present invention,
FIG. 4 shows one embodiment of the direction detection section of the present invention, FIG. 6 shows another embodiment, and FIG. 5 shows an enlarged example of a line image for explaining the present invention. FIGS. 7 and 8 are explanatory diagrams of an example of operation when the present invention is applied to a drawing reading device. In the figure, 1
is a rectangular photoelectric conversion element, 2 is a load resistance, 3 is an output line,
4 is a direction detection section, 5 is a detection signal line, and 10 is a direction detection eye of the present invention.

Claims (1)

[Claims] 1. A photoelectric conversion means in which a plurality of rectangular photoelectric conversion elements are arranged side by side on a plane, means for projecting an optical image of a part of a line figure onto a light receiving surface of the photoelectric conversion means, and a photoelectric conversion element of the photoelectric conversion means. means for receiving and determining the direction of the output signal of the
An eye for detecting the direction of a line figure, characterized in that it detects whether the direction of the line figure is in a predetermined direction.