JPS59178028A - System for transmitting specific information - Google Patents

Abstract

PURPOSE:To attain transmission of information without using a modulator by providing a means reflecting incident light in a direction identical to the incident direction regardless of an incident angle and a means scanning turnably light having a sharp directivity toward an optical reflecting means. CONSTITUTION:A mobile body 2 includes a laser scanner 21. When a laser light irradiated from the laser scanner 21 scanning turnably the laser light toward an external part come into contact with a corner cube 10, the corner cube 10 reflects the laser light in a direction identical to the incident direction, i.e., the direction toward the laser scanner 21. The laser scanner 21 is provided with a photodetector, which converts the reflected light from the corner cube 10 into an electric signal. The output of the photodetector is counted by a counter 22 and fed to a discriminator 23. The discriminator 23 analyzes the information transmitted from the corner cube 10 based on the counter output of the counter 22. The result of discrimination of the discriminator 23 is fed to a device 24 for utilizing the result of discrimination.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a unique information transmission system, and more particularly to a system for transmitting unique information using, for example, sharply directional light.

Description of Prior Art Conventionally, light reflecting devices have been put into practical use that reflect incident light in the same direction as the incident light regardless of its angle of incidence. This is, for example, called a corner cube and is commercially available.

FIG. 1 is an illustrative diagram for explaining the optical properties of the above-mentioned corner cube. Although not shown in the figure, the corner cube 1 is constructed by, for example, three-dimensionally combining a plurality of light-reflecting mirror surfaces. Therefore, the light incident on the corner cube 1 is reflected multiple times by the light reflecting mirror surface inside the corner cube 1 and exits to the outside. Now, the angle of incidence θ1 on corner cube 1 is
Let's consider the incident light. This incident light A is reflected by the light reflecting mirror surface inside the corner cube 1, and the reflected light A'
It emits as. At this time, the reflected light A' is parallel to the incident light Δ, and its reflection angle is equal to the incident angle of the incident light A. Therefore, the reflected light A' is reflected in the same direction as the direction in which the incident light A has entered. This relationship holds true regardless of the angle of incidence of the incident light. For example, the incident light B and the reflected light B' are parallel, and the incident angle of the incident light B and the reflection angle of the reflected light B' are both equal to 02.

As mentioned above, since corner cubes have unique optical properties, they can be used in various fields, and methods of using them are currently being actively researched and developed.

By the way, there has been a request to transmit information using the reflected light of this corner cube. however,
Since the corner cube only has the function of reflecting incident light in the same direction, it cannot transmit information by itself.

Therefore, it was necessary to newly provide a modulation device for modulating the reflected light from the corner cube.

Although such a modulation device is effective in transmitting complex information, it has the drawback that it is too large and expensive to transmit simple information.

OBJECTS OF THE INVENTION Therefore, the main object of the present invention is to provide a unique information transmission system which allows information to be transmitted without the use of any modulation device.

Summary of the Invention In summary, the present invention includes a light reflecting means that reflects incident light in the same direction as the direction of the incident light regardless of the incident angle, and a rotating scanning device that directs sharply directional light toward the light reflecting means. A mask is formed in a predetermined area of the light reflecting mirror surface of the light reflecting means, thereby causing the reflected light of the light reflecting means to include unique information.

The above objects and other objects and features of the present invention will become more apparent from the following detailed description with reference to the drawings.

DESCRIPTION OF THE EMBODIMENT FIG. 2 is a schematic block diagram showing an embodiment of the present invention. In the figure, the moving body 2 includes a laser scanner 21. This laser scanner 21 rotates and scans a laser beam toward the outside. When the laser beam emitted from the laser scanner 21 hits the corner cube 10, the corner cube 1o reflects the laser beam in the same direction as the direction of incidence, that is, in the direction of the laser scanner 21. laser scanner 2
1 is provided with a light receiving element (not shown), which converts light reflected from the corner cube 1o into an electrical signal.

The output of this light receiving element is given to a counter 22 and counted. The count output of the counter 22 is given to the judgment device 23. This judgment device 23 analyzes the information transmitted from the corner cube 10 based on the count output of the counter 22.The judgment result of the judgment device 23 is sent to a utilization device (for example, a position calculation device, an automatic steering device 1 display device, etc.) 24. Given.

FIG. 3 is a diagram showing the relationship between the light reflecting mirror surface of the corner cube 1o shown in FIG. 2 and the reflected light. Note that this FIG. 3 shows a top view of the corner cube 1o. The light reflecting mirror surface 11 is formed by, for example, three light reflecting mirror surfaces 11a to 11C being three-dimensionally combined. Light reflecting mirror surface 11a
For some parts, for example, paint or paper, J, mask 1
2 is formed to prevent light from hitting it. This mask 12 is formed so that it looks like a sector when viewed from above the corner cube 10.

Since the light incident on the portion where the mask 12 is formed does not hit the light reflecting mirror surface 11a, it is not reflected in the same direction as the direction of the incident light. By the way, the region 13' indicated by the dotted line in FIG. 3 is optically affected by the mask 12 (
This is an area where That is, the light incident on this region 13' is not reflected in the same direction as the direction of the incident light. This is because, as explained in Fig. 1, the light incident on the corner cube is reflected multiple times by the internal reflecting mirror surface and then exits from a different position from where it entered.
This is because the light incident on 3' hits the mask 12 while being reflected multiple times by the light reflecting mirror surfaces 118 to 11C. In addition,
Of course, the same effect can be obtained even if a mask is formed in the region 13'.

Suppose now that the laser beam LB from the laser scanner 21 crosses the light reflecting mirror surface 11 in the direction of the arrow.

In this case, when the laser beam LB hits the portion a, the laser beam 1B is reflected in the direction of the laser scanner 21. Next, when the laser beam 1B crosses the mask 12 and its symmetrical region 13', that is, t5b; . Also, when the laser beam LB crosses the part d, the laser beam B is opposite to the direction of the laser scanner 21! ) Iξ can be. Therefore, the reflected light from the corner cube 10 has two
The pulse and su components will be 0. Here,
Even if the direction in which the light 1B traverses is slightly changed, the reflected light from the corner cube 10 always contains two pulses.

The counter 22 of the moving body 2 counts the pulse components included in this reflected light.

FIG. 4 is a diagram showing another example of the light reflecting mirror surface of the corner cube 10. In this example, two rows of masks 14 and 15 are formed on the light reflecting mirror surface 11a.

Note that regions 14' and 15' indicated by dotted lines are regions that are optically affected by the masks 14 and 15, respectively, and the light incident on these regions is reflected in the region 13 described above.
As in the case of ', it is not reflected in the direction of the incident light. When the laser beam LB traverses such light reflecting mirror surfaces 11a to 11c as shown by the arrows, the reflected light from the corner cube 10 will contain five pulse components.

FIG. 5 is an illustrative diagram showing an example of a moving body position detection system using the present invention. In the figure, corner cubes 108 to 10d are arranged in the moving area of the moving body 2. As described above, a mask is formed on the light reflecting mirror surface of each corner cube 108-10d. Here, this mask is formed so that the reflected light of each of the corner cubes 10a to 10 (I) reflects a different number of pulse components.

Therefore, the reflected light from each of the corner cubes 108 to 10d contains unique information.

This unique information, that is, the number of pulse components, is divided by the counter 22 of the moving body 2 and is given to the judgment device @23. The determination device 23 stores in advance information specific to each of the corner cubes 1Qa to 10υ. Therefore, judgment device 2
3, it is determined from which corner cube the reflected light ζ is received by comparing the 5j number of the counter 22 with the unique information stored in advance. Judgment device 2
The YiJ cutting result of 3 is given to the (・υ equipment H24. The utilization device 24, for example,
The counter position information of d is stored in advance. Then, based on the determination result given by the determination device 23, the corresponding absolute device information is read out, and the current position of the moving object 2 is determined or displayed. At this time, the corner cube 'l Oa ~ 10
If the rotation angle (α1, α2) of the laser skier V 21 upon receiving the reflected light from d is used as a parameter for position calculation, very accurate position calculation can be performed.

In the embodiment described above, the unique information is expressed by the number of pulse components included in the reflected light from the corner cube 10, but instead of this, the unique information may be expressed by the pulse width of the pulse components included in the reflected light. You can also do this. In this case, a pulse width detection circuit may be used in place of the counter 22 to detect the unique information.

Effects of the Invention As described above, according to the present invention, specific information can be included in the reflected light of the light reflecting means without providing any modulation device, and information can be transmitted.

Therefore, the device becomes very simple and inexpensive.

Furthermore, since no modulation device is provided, there is no need for adjustments, maintenance, and inspections.

[Brief explanation of drawings]

FIG. 1 is an illustrative diagram for explaining the optical properties of a corner cube. FIG. 2 is a schematic block diagram showing one embodiment of the present invention. FIG. 3 is a diagram showing the relationship between the mirror surface of the corner cube 0 shown in FIG. 2 and its reflected light. FIG. 4 is a diagram showing an example of a pond on the light reflecting mirror surface of the corner cube 10. FIG. 5 is an illustrative diagram showing an example of a moving body position detection system using the present invention. In the figure, 10 is a corner cube, 11a to 11C are light reflecting mirror surfaces, 12, 14 and 15 are mass blocks, and 21 is a laser scanner. Patent applicant Toshihiro Okimura

Claims (2)

[Claims] (1) A light reflecting means having a light reflecting mirror surface and reflecting light incident on the light reflecting mirror surface in the same direction as the direction of the incident light regardless of the angle of incidence, and directing sharply directional light toward the light reflecting means. (a light scanning means for rotating and scanning the light reflecting means; and a mask formed in a predetermined area of the light reflecting mirror surface of the light reflecting means in order to include unique information in the reflected light of the light reflecting means; A unique information transmission system that transmits unique information from a light reflecting means side to the optical scanning means side. (2) Unique information according to claim 1, characterized in that a plurality of the light reflecting means are arranged, and the mask is formed so that the reflected light of each light reflecting means contains different information. transmission system.