JP2011114790A - Detection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a detection system capable of reducing a commercial price by comparing whether or not laser light is radiated with a detectable range, and further, even when any other light than laser light is present, detecting the light with high accuracy. <P>SOLUTION: In a detection system 1, a transmitter 3i irradiates a solar cell of a receiver 5 with laser light to which fluctuation has been given corresponding to a digital signal of a digital signal generating part. The receiver 5 receives light utilizing power generation by the solar cell in a solar cell power generator and further efficiently removes influences of disturbance utilizing a detection signal of an environmental light detecting part, in a differential part. Thus, an irradiation determining part can highly accurately determine whether or not the solar cell is irradiated with laser light. Moreover, in a data extracting part, processing for extracting digital data included in laser light, with which the solar cell is irradiated, can be implemented. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a detection system, and more particularly to a detection system including a transmission device that generates laser light and a reception device that receives light other than laser light by a solar cell and generates power.

  2. Description of the Related Art Conventionally, for example, a photo IC that detects whether or not a laser beam is irradiated is known (see Non-Patent Document 1).

Hamamatsu Photonics Co., Ltd., “Photo IC”, [online], Internet <URL: http://jp.hamamatsu.com/products/sensor-ssd/pd089/index_en.html>

  However, the conventional laser beam irradiation detection device is expensive. Therefore, when detecting the presence / absence of irradiation in a wide range as compared with the cross section of the laser beam, it is enormously expensive and difficult to commercialize.

  Therefore, the present invention proposes a detection system that can reduce the realization cost compared to a range in which the presence or absence of laser light irradiation can be detected, and can detect with high accuracy even if light other than laser light is present. For the purpose.

  The invention according to claim 1 is a detection system including a transmitting device that generates laser light and a receiving device that generates light by receiving light other than the laser light by a solar cell, and the receiving device has a light receiving area. Is wider than the cross section of the laser beam, and generates an electric power generation signal indicating the amount of electric power generated by receiving light by the solar cell, and an environment for generating a detection signal indicating the detected amount by detecting the received light amount The power generation signal and the detection signal are compared with the light detection means in a state where the laser beam is not received, and the power generation signal or / and the detection signal are amplified or / and attenuated, and the two match. Adjusting means for adjusting so that the transmission device generates a digital signal corresponding to the digital data, a power supply means for supplying power, and the laser light And a light emission control means for controlling the light emission of the light emission means by giving fluctuation to the power supplied by the power supply means corresponding to the digital signal when the light emission means is caused to emit light. The solar cell power generation means is irradiated with the laser light after adjustment by the adjustment means, and the receiver subtracts the detection signal from the power generation signal after adjustment by the adjustment means. Or, a difference unit that subtracts the power generation signal from the detection signal to extract a difference signal, and an irradiation determination unit that determines whether the laser light is irradiated on the solar cell power generation unit based on the difference signal; And a data extracting means for obtaining digital data from the difference signal when it is irradiated.

  The invention according to claim 2 is the detection system according to claim 1, wherein there are a plurality of the transmission devices, and each of the data generation means generates a digital signal corresponding to digital data different from other transmission devices. Each of the light emission control means has a first voltage that is greater than a light emission limit voltage of the light emission means and less than a laser rated output voltage, and a second voltage that is greater than the first voltage and less than or equal to the laser rated output voltage. The laser light is generated by adjusting the voltage applied to the light emitting means corresponding to each bit of the digital data generated by the digital signal generating means to the first voltage or the second voltage to generate the laser light. Voltage level converting means for generating the data without interruption, and the receiving device is configured to perform the duplication based on the digital data obtained by the data extracting means. Of the transmission device comprises a data processing means for identifying the transmitting apparatus is irradiated with laser light to the solar cell power generation means.

  The invention of the present application may be regarded as a transmission device invention, a reception device invention, a detection method invention, a program invention, and a computer-readable recording medium recording the program.

According to the invention according to each claim of the present application, when detecting the presence / absence of laser light irradiation in an environment where disturbance (miscellaneous light) such as sunlight or room light exists, the presence / absence of laser light is detected using a solar cell. By detecting, the realization price can be greatly reduced compared to the detectable range. For example, in the case of a conventional photo IC, the size is 0.5 × 0.5 mm (0.25 mm ² ) and the price is ¥ 250. On the other hand, the solar cell has a size of 50x30 mm (1,500 mm ² ) and a price of 100 yen. Therefore, the cost of the photo IC corresponding to the solar cell area is 15,000 times.

  Furthermore, for radio waves and the like, a technique for transmitting a signal on a carrier wave and transmitting it far away is known. For example, even if light from a light bulb or the like is focused by a lens, it may be possible to transfer analog data such as sound. However, with a light source such as a light bulb, it is difficult to transfer while clearly distinguishing 0 and 1 necessary for digital data transfer. The laser light has a constant wavelength and excellent directivity. Furthermore, it has become clear that laser light has a high response to hysteresis during the development process of the inventors. Therefore, in the present invention, by using laser light, it becomes possible to transfer digital data stably and at high speed. Further, it is easy to specify a communication target, information can be sent only to an irradiation target, and information leakage occurs. It has an advantage over it.

  However, if the laser light is detected only by the solar cell, it reacts sensitively to light such as a fluorescent lamp or an incandescent lamp, and the signal is not stable. Therefore, even if digital data is placed on a laser beam and received by a solar cell to generate power, it is difficult to efficiently remove the influence of disturbance with accuracy that enables digital data transfer. According to the present invention, by obtaining the differential signal using the detection signal of the ambient light detection means, it is possible to realize high-performance digital data transfer with a simple configuration and excluding the influence of disturbance.

  Furthermore, as in the invention according to claim 2 of the present application, when there are a plurality of transmitting devices, each transmitting device transfers unique digital data to the receiving device, so that the receiving device irradiates the solar cell. Can be identified.

It is a block diagram which shows the outline | summary of a structure of the detection system 1 which concerns on the Example of this invention. It is a block diagram which shows an example of a structure of the transmitter 3 _i of FIG. An example of voltage level conversion of the voltage level converter 19 _i of FIG. 2 will be described. It is a block diagram which shows the outline | summary of a structure of the receiver 5 of FIG. FIG. 5 is a flowchart showing an example of the operation of the receiving device 5 in FIG. 4. It is a graph which shows an example of the electric power generation signal of the solar cell power generation part 31 of FIG. It is a graph which shows an example of the signal which the ambient light detection part 33 of FIG. 4 detected. It is a graph which shows the signal after the voltage level conversion by the voltage level conversion part 49 of FIG.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to this embodiment.

First, with reference to FIG. 1, the structure of the detection system 1 which concerns on the Example of this invention is demonstrated. The detection system 1 includes N transmission devices 3 ₁ ,..., 3 _N (hereinafter, subscripts are omitted when there are a plurality of transmission devices 3 ₁ ,. And a receiving device 5 that generates light by receiving light other than laser light by a solar cell. The transmission device 3 _i (i is a natural number equal to or less than N) is, for example, a laser pointer that is carried by the user and irradiates the receiving device 5 with the laser beam 7, and the user controls whether or not the laser beam is irradiated. It is possible to change the irradiation direction when it is irradiated. For example, the receiving device 5 determines the presence or absence of laser light irradiation, or identifies the transmitting device 3 that has irradiated the laser light 7. The N transmitting devices 3 and the receiving devices 5 are, for example, N players 9 ₁ ,..., 9 _N and 1 player 9 _{N + 1} each having two attackers and defenders. Used for games divided into teams. In this game, each attacking player 9 _i has a transmitting device 3 _i , and the defending player 2 _{N + 1} has a receiving device 5.

Next, with reference to FIG. 2, each transmission device 3 _{i in} FIG. 1 will be specifically described. Each transmission device 3 _i includes a digital signal generation unit 11 _i that generates a digital signal corresponding to predetermined digital data (for example, digital data different from other transmission devices), a power supply unit 13 _i that supplies power, A light emitting unit 15 _i that emits laser light (for example, a semiconductor laser), whether or not the light emitting unit 15 _i emits light, and the power source unit 13 _i corresponding to the digital data generated by the digital signal generating unit 11 _i when emitting light. Has a light emission control unit 17 _i for controlling the light emission of the light emitting unit 15 _i by fluctuating the electric power supplied by the.

The light emission control unit 17 _i includes a voltage level conversion unit 19 _i that converts the voltage level of the digital signal indicating the digital data generated by the digital signal generation unit 11 _i , and the converted signal and voltage of the voltage level conversion unit 19 _i. A mixing unit 21 _i (for example, a mixer) that mixes the electric power of the unit 13 _i is included.

Subsequently, the voltage level conversion processing of the voltage level conversion unit 19 _i will be described with reference to FIG. When the light emitting unit 15 _i falls below the light emission limit voltage, the resonance circuit that generates laser light is not driven, and thus the laser light is cut off (Off). That is, as shown in FIG. 3, when the TTL threshold value of the digital signal is lower than the light emission limit voltage, the laser light is interrupted even if the digital signal is input to the laser light emitting unit without changing the TTL level. Similarly, TTL Hi is usually different from the laser rated output level. This causes noise on the digital data, and the user cannot confirm the laser beam. Therefore, the voltage level converter 19 _i sets the laser digital signal level and converts the level of the TTL level digital data. That is, the voltage level applied to the light emitting portion 15 _i by mixing unit 21 _i, set the Hi level to the laser rated output voltage, adjusts the Lo level emission limit voltage. By setting the voltage level in this way, it is possible to transfer the signal without interrupting the laser beam (that is, the laser beam can be generated by giving fluctuations).

  The laser light has a constant wavelength and excellent directivity. Furthermore, in the development process of the inventors, the laser beam has a high response to hysteresis (that is, the Hi and Lo levels are rapidly reproduced even when laser light having a uniform wavelength is applied with data by the light emitting unit 13). It was revealed that the following ability is high. In the data transmission in the negative logic circuit, the high followability from Hi → Lo → Hi increases the reliability of data transmission. Due to this characteristic, the detection system 1 can cope with high-speed digital communication. Therefore, by using laser light, it is easy to specify the communication target, information can be sent only to the irradiation target, and there is an advantage over information leakage, and furthermore, digital data can be transferred stably and at high speed. It becomes possible.

Note that the digital signal generation unit 11 _i of this embodiment is realized by an embedded microcomputer and the like, and digital data is assumed to be predetermined, but the present invention is not limited to this. For example, the digital signal generation unit may be one that receives digital data generated by another device such as a personal computer, or one that converts analog data detected by a sensor or the like into digital data. Further, the voltage level converter 19 _i corresponds to two different voltages between the laser rated output voltage and the emission limit voltage corresponding to the Hi level and the Lo level of the digital signal level for laser (the first level of the claims of this application). It may be adjusted so as to be an example of a voltage and a second voltage.

  Referring to FIG. 1, the receiving device 5 detects the amount of light detected by detecting the amount of light received by the solar cell power generation unit 31 as a main sensor that generates a power generation signal indicating the amount of power generated by receiving light from the solar cell. An ambient light detector 33 as a secondary sensor for generating a detection signal indicating

  The solar cell power generation unit 31 is realized by a solar cell panel, for example. The light receivable area of the solar cell panel of the solar cell power generation unit 31 is wider than the cross section of the laser beam generated by the light emitting unit 13. Thus, by detecting laser light using a solar cell panel, it becomes possible to significantly reduce the realization price compared to the detectable range.

  The ambient light detection unit 33 is realized by, for example, a semiconductor panel (for example, a CdS photoconductive cell). If the laser light is detected only by a solar cell, it reacts sensitively to a fluorescent lamp or an incandescent lamp, and the signal is not stable. Therefore, even if digital data is placed on a laser beam and received by a solar cell to generate power, it is difficult to efficiently remove the influence of disturbance with accuracy that enables digital data transfer. In this embodiment, both the solar cell panel and the semiconductor panel change in the current flow when receiving light. Therefore, the miscellaneous light is detected by both the main sensor and the sub sensor, and the laser light is detected by the main sensor. Therefore, by obtaining the differential signal using the detection signal of the ambient light detection unit 23, it is possible to detect the signal from the laser light without the influence of disturbance and perform high-performance digital data transfer.

  The receiving device 5 further compares the power generation signal with the detection signal in a state where no laser beam is received, amplifies or attenuates the detection signal, and adjusts the two so that they match. It has the adjustment part 35 which maintains the state of amplification or attenuation. The solar cell power generation unit 21 is irradiated with laser light after adjustment by the adjustment unit 35.

  The receiving device 5 further performs a filtering process such as subtracting the detection signal adjusted by the adjusting unit 35 from the power generation signal to extract a difference signal, and removing a carry signal (carrier wave) from the difference signal. A filter processing unit 39 having a digital signal processing unit 47 to perform, a determination unit 41 for determining whether the solar cell power generation unit 31 is irradiated with laser light based on the difference signal after the filter processing, and irradiation. In some cases, the data extraction unit 43 that obtains digital data from the difference signal, and the solar cell power generation unit 31 that is irradiated with laser light among the plurality of transmission devices 3 based on the digital data obtained by the data extraction unit 43, for example A data processing unit 45 for identifying

The data extraction unit 43 includes a voltage level conversion unit 49 that changes the voltage level of the difference signal processed by the filter processing unit 39 when it is determined that the irradiation determination unit 41 is irradiated. This is, for example, a conversion opposite to that of the voltage level conversion unit 19 _i in FIG. 2, which converts the laser rated output voltage to the TTL Hi level and converts the laser emission limit to the TTL Lo level.

  Next, an example of the operation of the detection system 1 will be described with reference to FIG.

  First, the adjustment unit 35 attenuates the output of the ambient light detection unit 33. Then, the adjustment unit 35 compares the power generation signal and the detection signal with reference to the difference signal in a state where the solar cell power generation unit 31 does not receive the laser light (step ST1), and determines whether they match (step ST1). ST2) If they do not match, the gain of the output signal from the ambient light detection unit 33 is increased (step ST3), and the process returns to step ST1. In step ST2, the matching stage is the adjustment stage, and when the adjustment stage ends, the adjustment unit 35 maintains the amplification or attenuation state of the detection signal.

In step ST2, the after match, the emission control unit 17 _i of each transmission device 3 _i, for example the user 9 _i of each transmission device 3 _i is in response to performing the operation on / off switch, the light emitting The unit 15 _i is controlled to generate laser light corresponding to the digital data. Further, the laser light has directivity, and even if the laser light is generated, it is not always irradiated to the solar cell panel. User 9 _i of each transmission device 3 _i is adjusted so that by using the visibility of the laser beam is irradiated with laser light to the solar cell panel.

  The difference unit 37 subtracts the detection signal from the power generation signal to extract a difference signal (step ST4). The filter processing unit 39 performs filter processing on the difference signal (step ST5). The irradiation determination unit 41 determines whether the solar cell power generation unit 31 is irradiated with laser light based on the difference signal after the filter processing (step ST6). If not, the process returns to step ST4. If it is irradiated, the data extraction unit 43 obtains digital data from the difference signal (step ST7), and returns to step ST4.

  In addition, the solar cell power generation unit 31 and the ambient light detection unit 33 may be realized by an integrated device, or the solar cell power generation unit 31 and the ambient light detection unit 33 are realized in separate devices. May be. Furthermore, all or part of the solar cell power generation unit 31 and the ambient light detection unit 33 may be realized so as to exist in a separate device from the other units of the reception device 5.

  Further, the adjustment unit 35 may amplify or attenuate the power generation signal, or may perform processing on both the power generation signal and the detection signal so as to amplify the power generation signal and attenuate the detection signal. .

  Next, an example of a signal when digital data is received by serial communication in the reception device 5 of FIG. 4 will be described with reference to FIGS. 6 to 8, the X axis indicates time, and one scale is 1.0 second. The Y axis indicates voltage, and one scale is 1.0V. The first grid line from the bottom is 0.0V. Here, a case where the transfer rate is transmitted by serial communication will be described as an example, but the present invention is not limited to such serial communication or the like.

FIG. 6 is a graph showing the power generation signal of the solar cell power generation unit 31 of FIG. 4 measured in the room during the daytime. The digital data of the transmitter 3 is character information of several bytes, and this is repeatedly transferred. Laser light loaded with digital data is irradiated at an arbitrary timing. This experiment was conducted under adverse conditions with strong natural light. In fact, in FIG. 6, the power generation signal confirms power generation near 3.6 V, which is the upper limit of electromotive force until time t ₀₁ (in particular, the maximum power generation amount can be confirmed for a moment). Thereafter, although power generation decreases from t ₀₁ to t ₀₂ , power generation near the upper limit of electromotive force is confirmed again from t ₀₂ to t ₀₃ , and power generation decreases after t ₀₃ .

  Under such strong light, the power generation voltage of the solar cell is maximized, and it may be difficult to extract digital data. Therefore, under strong natural light, for example, the system receiver is placed in a dark acrylic box, and a filter typified by sunglasses is added to the surface of the solar cell to reduce the input to the solar cell, and the laser light. Can be detected. Furthermore, change the color (red, green) and output of the semiconductor laser, select a filter (color and darkness) according to the conditions under which this system is used, and change the type (electromotive force) of the solar cell. It may be. By taking such measures, sufficient detection can be performed not only indoors but also outdoors where there is sunlight such as intense western sunlight.

  FIG. 7 is a detection signal of the ambient light detection unit 33 in FIG. It is confirmed from this detection signal that a change in indoor brightness has been detected. However, in FIG. 6 and FIG. 7, the change is the same, but the resulting voltage is different. The adjustment unit 35 adjusts this difference.

  FIG. 8 is a graph showing a signal after conversion by the voltage level conversion unit 49 of FIG. The presence / absence of light reception from the laser beam is detected from the differential signal after adjustment by the adjustment unit 35, and further, the laser emission limit power and the laser rated output voltage are converted (in this experiment, 0.0 V and 5.0 V, respectively). However, the present invention is not limited to this conversion.) Thereby, it can be confirmed that digital data can be extracted.

  Based on the digital data obtained by the data extraction unit 35, the data processing unit 37 performs data processing (for example, identification processing of the plurality of transmission devices 3 that irradiate the solar cell power generation unit 21 with laser light). . By such data processing, for example, each transmitting device 3 transfers unique digital data to the receiving device, and the receiving device 5 can identify the transmitting device that irradiates the solar cell.

  Therefore, for example, the present invention can determine who has irradiated in a battle game using laser light, and can make the battle game more interesting. Furthermore, in museums and art galleries, if the transmission device of the present invention is realized by a laser pointer that can be carried by each visitor, and the visitor irradiates a predetermined solar cell with the laser pointer, an explanation according to each visitor is provided. Services such as performing can be realized.

1 detection system, 3 _1, · · ·, 3 _N transmission apparatus, 5 receiving apparatus, 11 _1, · · ·, 11 _N digital signal generating unit, 13 _1, · · ·, 13 _N Power unit, 15 _1, · · ·, 15 _N-emitting portion, 17 _1, · · ·, 17 _N light emission control section, 19 _1, · · ·, 19 _N voltage level converting unit, 21 _1, · · ·, 21 _N mixing unit, 31 solar cell Power generation unit, 33 Ambient light detection unit, 35 Adjustment unit, 37 Difference unit, 41 Irradiation determination unit, 45 Data extraction unit, 47 Data processing unit

Claims (2)

A detection system comprising a transmitter for generating laser light and a receiver for receiving light other than the laser light by a solar cell to generate power,
The receiving device is:
A solar cell power generation means for generating a power generation signal indicating a power generation amount received by the solar cell and generated by receiving light from the solar cell, the light receiving area being wider than the cross section of the laser beam;
An ambient light detection means for detecting a light amount received and generating a detection signal indicating a detection amount;
The power generation signal and the detection signal are compared without receiving the laser beam, and the power generation signal or / and the detection signal are amplified or / and attenuated and adjusted so that they match. Adjustment means,
The transmitter is
Digital signal generating means for generating a digital signal corresponding to the digital data;
Power supply means for supplying power;
A light emitting means for generating the laser light;
Whether to emit light from the light emitting means, and when emitting light, has a light emission control means for controlling the light emission of the light emitting means by giving fluctuation to the power supplied by the power supply means corresponding to the digital signal,
The solar cell power generation means is irradiated with the laser light after adjustment by the adjustment means,
The receiving device is:
Subtracting the detection signal from the power generation signal after adjustment by the adjustment means or subtracting the power generation signal from the detection signal to extract a difference signal;
Irradiation determining means for determining whether or not the laser light is irradiated on the solar cell power generation means based on the difference signal;
A detection system comprising data extraction means for obtaining digital data from the difference signal when irradiated. There are a plurality of the transmission devices, the user can control the presence or absence of laser light irradiation and can change the irradiation direction when irradiated,
Each of the data generation means generates a digital signal corresponding to digital data different from other transmission devices,
Each of the light emission control means has the digital signal generating means for a first voltage that is greater than a light emission limit voltage of the light emission means and less than a laser rated output voltage and a second voltage that is greater than the first voltage and less than or equal to the laser rated output voltage By adjusting the voltage applied to the light emitting means corresponding to each bit of the digital data generated by the above to the first voltage or the second voltage and generating the laser light, the laser light is not interrupted. Voltage level conversion means for generating,
The receiving device has data processing means for identifying a transmitting device that irradiates the solar cell power generation means with laser light, based on the digital data obtained by the data extracting means. Item 2. The detection system according to Item 1.

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