JPH01199169A - Probe using optical fiber and light transmission device and light reception device used therefor - Google Patents

Abstract

PURPOSE:To enable the reliable transmission of a signal observed from a specimen, by using an optical fiber as a signal transmission medium. CONSTITUTION:A signal detection terminal 3 of a probe is connected to a prescribed part 2 to be observed of a specimen 1. An electric signal detected from this terminal 3 is converted into a light signal in a light transmission element 4 and transmitted through an optical fiber 5 as a signal transmission medium, and it is converted into an electric signal in a light reception element 6. This electric signal is inputted to an oscilloscope 8 through a BNC cord 7 and monitored. Since the signal is transmitted by the probe using the optical fiber in this way, it is not affected by an electromagnetic ambience around the probe, and thus the signal detected at the part to be observed can be transmitted reliably.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a probe used to guide signals observed in a harsh environment where an electromagnetic field is applied to monitoring equipment such as an oscilloscope. be.

[Prior Art] Conventionally, electric wires have been generally used as a signal transmission medium between a part to be observed such as an electric circuit using a probe and a monitoring device such as an oscilloscope.

[Problems to be Solved by the Invention] When a signal waveform is measured by a probe using an electric wire as a signal transmission medium, there are no particular problems under normal circumstances. However, for example, when measuring with a probe using an electric wire in a harsh environment where an electromagnetic field is applied, the probe itself senses noise and the signal to be measured is disturbed, making it difficult to transmit a faithful signal to an oscilloscope, etc. However, there was a drawback that it was not possible to monitor accurate waveforms. In addition, when conducting an EMI test (electric field strength test), when attempting to accurately observe the waveform of the measured object, for example, waveform changes, pulse cracking, etc. due to the EMI test, for the same reason as above, There is a problem in that it is not possible to distinguish whether the object to be measured itself malfunctions due to the application of an electric field or whether noise is picked up during the signal transmission through the probe and the signal waveform is disturbed.

Therefore, this invention was made to solve the above-mentioned problems, and the probe itself is not subjected to electromagnetic induction in an environment where an electromagnetic field is applied (and the probe is not observed from the object to be measured). The object of the present invention is to provide a probe that can faithfully transmit signals.

[Means for Solving the Problems] A probe according to the present invention uses an optical fiber to transmit an observed signal to a monitoring device such as an oscilloscope. This probe includes a signal detection section that detects a signal from a predetermined observation site, an optical transmission section that converts the electrical signal extracted from the signal detection section into an optical signal, and an optical fiber section that transmits the optical signal. and an optical receiver that converts the transmitted optical signal into an electrical signal.

Preferably, the signal detecting section, optical transmitting section, optical fiber section, and optical receiving section in the probe of the present invention constitute one connected body.

The optical transmitting device used in the probe having this optical fiber includes a light emitting element that converts an observed electrical signal into an optical signal, a driving means for driving the light emitting element, and a power source that supplies current to the driving means. It is equipped with

Preferably, the power source is constituted by a battery, and the lead frame of the light emitting element constitutes a terminal of the signal detection section of the probe. This optical transmitter also includes a connection part with the terminal of the signal detection part of the probe and a connection part with the optical fiber, and the inside thereof is filled with resin and the outside thereof is covered with conductive resin or metal. Preferably, it is integrally formed.

Furthermore, the optical receiving device used in the probe having this optical fiber includes a light receiving element that converts the received optical signal into an electrical signal, an amplifying means that amplifies the electrical signal, and a binarization of the amplified electrical signal. and a power source for operating the amplification means and the binarization means.

Preferably, the power source is constituted by a battery.

In addition, this optical receiving device includes a connector that can be connected to an oscilloscope and a connection part with an optical fiber, and is integrally formed by filling the inside with resin and covering the outside with conductive resin or metal. is desirable.

[Operation] Since the probe of this invention uses an optical fiber as a signal transmission medium, the probe itself is not subjected to electromagnetic induction by electromagnetic fields in the surrounding environment, and the signal observed from the object to be measured can be faithfully transmitted. The information is then transmitted to monitoring equipment such as an oscilloscope.

Furthermore, in the probe of the present invention, by forming the signal detecting section, optical transmitting section, optical fiber section, and optical receiving section into one connected body, similar to a probe using a conventional electric wire,
Its handling can be facilitated.

In this invention, the power supply for driving the optical transmitting device is performed by the power source provided in the device itself. Further, the device itself is also equipped with a power source as a driving source for the optical receiving device. Therefore, there is no need to connect an electric wire for power supply from the outside, and there is no influence of electromagnetic induction, which is preferable in terms of making the device more compact.

Furthermore, if the lead frame of the light emitting element in the optical transmitter is configured as the terminal of the signal detection section of the probe, there is no need to attach or detach the signal detection terminal via the connector.

It is also possible to make the overall device configuration compact by integrally forming the probe including the connection part with the terminal of the signal detection part of the probe and the connection part with the optical fiber. Also,
The optical receiving device can also be integrally formed including a connector connectable to an oscilloscope and a connecting portion to an optical fiber, thereby making it possible to make the overall device configuration compact.

[Embodiment] FIG. 1 is a diagram schematically showing a probe using an optical fiber according to the present invention, and shows an example in which the probe is used for connection between an oscilloscope and an object to be measured. In the figure, a signal detection terminal 3 of a probe is connected to a predetermined observation site 2 of an object 1 to be measured. In this connection, one end of the signal detection terminal 3 is connected to the observed part 2, and the other end is connected to GND.
Connected to the terminal. Electric signals detected from the signal detection terminals 3 connected in this way are converted into optical signals in the optical transmitter 4. This optical signal propagates through an optical fiber 5 as a signal transmission medium, and is converted back into an electrical signal at an optical receiver 6 connected to the end of the optical fiber 5. This electrical signal is inputted to an oscilloscope 8 as a monitoring device through the BNC code 7, and the waveform of the signal observed at a predetermined observation site 2 is monitored by the oscilloscope 8.

The signal waveform monitored in this way is not affected by the electromagnetic environment around the probe because the signal is transmitted by the probe using an optical fiber, and the signal detected at the observation site 2 is not affected by the electromagnetic environment around the probe. Faithful reproduction When using a probe using an optical fiber connected between an oscilloscope and a site to be observed as described above, the optical receiver 6 can be reproduced by extending the optical fiber as a transmission medium as necessary. Since the subsequent part on the oscilloscope 8 side can be placed in a normal environment (outside a shielded room, outside an anechoic chamber, inside a dedicated measurement room, etc.), extremely reliable signal observation is possible. As shown in FIG. 2, the parts after the optical receiver 6 are placed in a normal environment, the signal detection terminal 3, the optical transmitter 4 and the optical fiber 5 are placed inside the shielded chamber 10, and the probe is connected. FIG. 2 is a schematic diagram illustrating an example. In the figure, an electronic control unit (ECU; El
electronic C.

ntrol Unit) is placed in an environment exposed to radio waves 9.

In addition, in this invention, by forming the signal detection section, optical transmission section, optical fiber section, and optical reception section into a single connected body, handling is not inferior compared to a conventional probe using an electric wire. .

As the optical transmitter used in the probe having the above-mentioned optical fiber, it is conceivable to apply an optical transmitter conventionally used for optical communication, which has the configuration shown in FIGS. 6A and 6B, for example.

The illustrated optical transmitter is an example of an optical transmitter used in an optical data link. FIG. 6A is a perspective view schematically showing a conventional optical transmitter, and FIG. 6B is a schematic block diagram of the optical transmitter module shown in FIG. 6A. In the figure, an electrical signal input to the optical transmission module 14 is converted into an optical signal by a light emitting element 41. The optical transmission module 14 is connected to the optical fiber 5 via the connector 11 in order to propagate this optical signal through the optical fiber and transmit it.

The optical transmitter module as an optical transmitter used in such optical data links requires connection to a power source of approximately +5V, for example, and an electric wire must be drawn together with the optical transmitter module to supply power from the outside. I had to turn it around.

Additionally, this optical transmitter module required a connector to connect to an optical fiber. Therefore, from the above, unlike when used for optical data links, when used as an optical transmitter for a probe using optical fiber,
Wires for power supply are susceptible to electromagnetic induction.
Since the connector must be connected and disconnected each time a signal is measured, there are problems such as the handling is complicated and the overall device configuration becomes large-scale.

Therefore, an optical transmitter for a probe using an optical fiber, which solves the above problems, provides easy power supply, and has a simple device configuration is schematically shown in FIG.

In the figure, this optical transmitter 4 includes a light emitting element 41, a driving section 42 for driving the light emitting element 41, and a driving section 42.
and a battery 43 that supplies power to the. An optical signal converted into an electrical signal by the light emitting element 41 is propagated to the optical fiber 5. Further, an electrical signal input to the optical transmitter 4 is transmitted through a signal detection terminal 3a extending from the end of the lead frame of the light emitting element 41.

It is detected by the GND connection terminal 3b. Each element constituting this optical transmitter 4 is integrally molded with a transparent resin 471; at the same time, its outer periphery is covered with a case 46 made of conductive resin or metal.

FIG. 4 is a schematic diagram showing another embodiment of the optical transmitter.

The optical transmitting device 4 shown in FIG. 4 differs from the device shown in FIG. 3 in that it does not include a built-in battery as a power source.

Therefore, as an alternative to batteries, the signal detection terminal 3a
, the voltage level of the observation signal detected by the GND connection terminal 3b is converted into a current via the resistor 43b, and the light emitting element 41 is driven. diode 43
A is incorporated for the purpose of preventing destruction of the light emitting element 41 due to reverse connection, surge, etc.

Furthermore, as an optical receiver used in the above-mentioned probe having an optical fiber, it is considered to apply an optical receiver conventionally used for optical communication, for example, having the configuration shown in FIGS. 7A and 7B. It will be done. The illustrated optical receiver is an example of an optical receiver used in an optical data link. FIG. 7A is a perspective view schematically showing a conventional optical receiving device, and FIG. 7B is a schematic block diagram of the optical receiving module shown in FIG. 7A. In the figure, an optical signal transmitted by an optical fiber 5 is input to an optical receiving module 16 via a connector 11. The optical signal input to the optical receiving module 16 is converted into an electrical signal by the light receiving element 61. At this time, the electrical signal is amplified by an amplifier circuit and then converted into a binary signal by a binarization circuit.

The optical receiving module, which serves as an optical receiving device used in such optical data links, requires connection to a power source of approximately +5V, for example, and in order to supply power from the outside, an electric wire must be drawn together with the optical receiving module. I had to turn it around. Additionally, this optical receiving module required a connector to connect to an optical fiber. Further, in this optical receiving module, external connection terminals 16a (power supply, GND, output) are provided in a direction perpendicular to the insertion direction of the optical fiber, and these terminals are connected to the system PC.
The structure is such that it is inserted into B and soldered.

Therefore, unlike when used for optical data links, when used as an optical receiving device for a probe using optical fiber, it is necessary to connect to the electric wire for power supply and to attach and detach the connector for each signal measurement. Since this is necessary, there are problems such as the handling becomes complicated and the overall device configuration becomes complicated.

Therefore, an optical receiving device for a probe using an optical fiber, which solves the above problems, facilitates power supply, and has a simple device configuration is schematically shown in FIG. In the figure, this optical receiver 6 includes a light receiving element 61 that converts an optical signal into an electrical signal, an integrated circuit 62 that amplifies and binarizes the electrical signal, and a battery 63 that operates the integrated circuit 62. It consists of The optical signal transmitted through the optical fiber 5 is input to the light receiving element 61. Further, the binarized electric signal is transmitted to a BNC cord connector 6 connected to the output end of the optical receiver 6.
5 to an oscilloscope as a monitoring device. Each element constituting the optical receiver 6 is integrally molded with a transparent resin 67, and at the same time, its outer periphery is covered with a case 66 made of conductive resin or metal. In addition,
The BNC cord connector 65 is connected to the optical receiver 6 for the purpose of connecting directly to an oscilloscope via a BNC cord.
It is built into.

Therefore, the signal detection section and the light transmission section, which constitute the probe of the present invention and are the only electrical parts exposed to an environment where an electromagnetic field is applied, drive the light emitting element (LED) and the light emitting element. Since it can be easily configured with the drive section, extremely compact implementation is possible, and reliability is not compromised by this part.

[Effects of the Invention] Since the present invention is configured as described above, it produces effects as described below.

Since this probe uses optical fiber as a signal transmission medium, it is suitable for observing the effects of radio wave interference on electronic control devices, and for observing signals from electronic control devices or electronic components installed in the engine compartment of automobiles, etc. It is effective to use the probe of the present invention for signal observation in harsh environments susceptible to electromagnetic induction, such as in fields where radio waves are exposed to electromagnetic induction.

Further, since the power source for driving the optical transmitting device or the optical receiving device used in this probe is provided in the device itself, there is no need to connect an electric wire to the device for power supply from outside. Furthermore, by configuring this power source with a battery or by configuring the lead frame of the light emitting element as a terminal of the signal detection section of the probe, the overall device configuration for signal detection by the probe can be simplified.

Furthermore, by integrally forming the optical transmission device with the terminal of the signal detection part of the probe and the connection part with the optical fiber, it is possible to configure a compact device, and the probe using the optical fiber can be connected to the normal electric wire. It can be handled in the same way as a probe using By integrally forming the optical receiving device itself together with a connector connectable to an oscilloscope and a connecting portion to an optical fiber, the configuration of the device can be made compact, and the same effects as described above can be achieved.

4. Brief explanation of the drawings Figure 1 is a schematic diagram showing an embodiment in which a probe using an optical fiber according to the present invention is connected between an object to be measured and an oscilloscope, and Figure 2 is a diagram according to the present invention. A schematic diagram showing an example in which a probe using an optical fiber is connected between an object to be measured that is affected by radio waves and an oscilloscope, and FIG. 3 is an example of an optical transmission device for a probe using an optical fiber according to the present invention FIG. 4 is a schematic diagram showing another embodiment of the optical transmitter according to the present invention, and FIG. 5 is a schematic diagram showing another embodiment of the optical transmitter according to the present invention. FIG. Schematic diagrams showing embodiments; FIGS. 6A and 6B are schematic perspective views of optical transmitting devices used in conventional optical data links, etc.;
Schematic block diagram of optical transmitter module, Figures 7A and 7B
The figure is a schematic perspective view showing an optical receiving device used in a conventional optical data link, etc., and a schematic block diagram of an optical receiving module.

In the figure, 1 is the object to be measured, 2 is the part to be observed, 3 is the signal detection terminal, 4 is the optical transmitter, 5 is the optical fiber, 6 is the optical receiver, 7 is the BNC code, 8 is the oscilloscope, and 9 is the radio wave. , 10 is a shielding chamber, 41 is a light emitting element, 42 is a drive unit, 43
．． 63 is a battery, 61 is a light receiving element, and 62 is an integrated circuit.

In each figure, the same reference numerals indicate the same or corresponding parts.

Figure 3 Figure 6A Figure 68

Claims (12)

[Claims] (1) A probe that transmits observed signals to a monitoring device such as an oscilloscope, which includes a signal detection section that detects a signal from a predetermined observed part, and an electrical signal extracted from the signal detection section into an optical signal. A probe using an optical fiber, comprising: an optical transmitting section for converting the optical signal; an optical fiber section for transmitting the optical signal; and an optical receiving section for converting the transmitted optical signal into an electrical signal. (2) The probe using an optical fiber according to claim 1, wherein the signal detecting section, the optical transmitting section, the optical fiber section, and the optical receiving section constitute one connected body. (3) An optical transmission device for a probe that transmits observed signals to a monitoring device such as an oscilloscope through an optical fiber, comprising a light emitting element that converts the observed electrical signal into an optical signal, and a drive that drives the light emitting element. An optical transmission device for a probe using an optical fiber, comprising: a means for driving the drive means; and a power source for supplying current to the driving means. (4) The optical transmission device for a probe using an optical fiber according to claim 3, wherein the power source is constituted by a battery. (5) The optical transmission device for a probe using an optical fiber according to claim 3 or 4, wherein the lead frame of the light emitting element constitutes a terminal of a signal detection section of the probe. (6) The optical transmitting device uses the optical fiber according to claim 3 or 4, which is integrally formed and includes a connection part with a terminal of the signal detection part of the probe and a connection part with the optical fiber. The optical transmitter of the probe. (7) The optical transmitter has an interior filled with resin,
7. The optical transmission device for a probe using an optical fiber according to claim 6, wherein the outside thereof is integrally formed by being covered with a conductive resin or metal. (8) An optical receiving device for a probe that transmits observed signals to a monitoring device such as an oscilloscope through an optical fiber, comprising a light receiving element that converts the received optical signal into an electrical signal, and an amplifier that amplifies the electrical signal. An optical reception probe using an optical fiber, comprising: a binarizing means for binarizing the amplified electric signal; and a power source for operating the amplifying means and the binarizing means. Device. (9) The optical receiving device for a probe using an optical fiber according to claim 8, wherein the power source is constituted by a battery. (10) The optical receiving device for a probe using an optical fiber according to claim 8 or 9, wherein the optical receiving device includes a connector connectable to an oscilloscope. (11) The optical receiving device for a probe using an optical fiber according to any one of claims 8 to 10, wherein the optical receiving device includes a connecting portion with the optical fiber and is integrally formed. (12) The probe using an optical fiber according to claim 11, wherein the optical receiving device is integrally formed by filling the inside with resin and covering the outside with conductive resin or metal. Optical receiver.