Testing apparatus for detecting an image signal in radio waves leaking from an information processing system

• US 5,465,112 A
• Filed: 12/02/1993
• Issued: 11/07/1995
• Est. Priority Date: 12/02/1992
• Status: Expired due to Term

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Nakao, Tomoyuki
• Primary Examiner(s): Groody, James J.
• Assistant Examiner(s): GRANT, CHRISTOPHER C
• Application Number:
  US08/160,211
• Time in Patent Office: 705 Days
• Field of Search: 348/192, 348/193, 348/180, 348/729, 348/184, 348/189, 348/1, 348/4
• US Class Current: 725/9
• CPC Class Codes: G01R 31/2825 in household appliances or professional audio/video equipment testing LAN's H04L43/50; testing TV systems H04N17/00; testing loudspeakers H04R29/00
• CPC Class Codes: H04N 17/00 Diagnosis, testing or measuring for television systems or their details

Abstract

A testing apparatus for detecting an image from an image signal in radio waves leaking from an information processing system. The information processing system uses horizontal and vertical synchronizing signals to display the image. The testing apparatus includes a radio wave receiving mechanism which receives the radio waves. An image signal detecting mechanism detects the image signal from the received radio waves and a synchronizing signal receiving mechanism receives the horizontal and vertical synchronizing signals from the information processing system. An image reproducing mechanism reproduces the image from the detected image signal by using the received horizontal and vertical synchronizing signals and a display device is used to display the reproduced image.

Claims

1. A testing apparatus for detecting an image from an image signal in radio waves leaking from an information processing system, the information processing system using horizontal and vertical synchronizing signals to display the image, the testing apparatus comprising:

radio wave receiving means for receiving the radio waves leaking from the information processing system;

image signal detecting means for detecting the image signal from the received radio waves;

synchronizing signal receiving means for receiving the horizontal and vertical synchronizing signals from the information processing system;

image reproducing means for reproducing the image from the detected image signal by using the received horizontal and vertical synchronizing signals; and

display means for displaying the reproduced image.

2. A testing apparatus as set forth in claim 1, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable.

3. A testing apparatus as set forth in claim 1, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises:

at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable;

an electro-optical transducer which is connected to the at least one cable to receive the horizontal and vertical synchronizing signals from the at least one cable and transduces the horizontal and vertical synchronizing signals into an optical signal;

an optical fiber which receives the optical signal from the electro-optical transducer and conducts the optical signal; and

an optical-electro transducer which is connected to the optical fiber to receive the optical signal via the optical fiber and transduces the optical signal into the horizontal and vertical synchronizing signals.

4. A testing apparatus as set forth in claim 1, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises:

at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable;

a transmitter which receives the horizontal and vertical synchronizing signals via the at least one cable and modulates a carrier signal by the horizontal and vertical synchronizing signals;

a transmitting antenna which is connected to the transmitter and transmits the modulated carrier signal as radio waves;

a receiving antenna which receives the radio waves transmitted by the transmitting antenna; and

a receiver, connected to the receiving antenna, which demodulates the radio waves received by the receiving antenna and reproduces the horizontal and vertical synchronizing signals.

5. A testing apparatus as set forth in claim 4, wherein the radio wave receiving means is also the receiving antenna.

6. A testing apparatus as set forth in claim 1, wherein the display means generates a magnetic field and the synchronizing signal receiving means comprises:

a magnetic sensor which senses the magnetic field generated by the display means and converts the strength of the magnetic field into an electrical signal;

a waveform shaping circuit which shapes the waveform of the electrical signal to reproduce the horizontal synchronizing signal; and

a frequency divider which divides the horizontal synchronizing signal reproduced by the waveform shaping circuit to reproduce a vertical synchronizing signal.

7. A testing apparatus as set forth in claim 6, wherein the waveform shaping circuit comprises an amplifier and an analog-to-digital converter.

8. A testing apparatus as set forth in claim 6, wherein the frequency divider comprises a programmable down counter and a digital switch.

9. A testing apparatus as set forth in claim 6, further comprising:

an electro-optical transducer which is connected to the waveform shaping circuit and the frequency divider and transduces the horizontal and vertical synchronizing signals reproduced, respectively, by the waveform shaping circuit and the frequency divider into an optical signal;

an optical fiber which receives the optical signal from the electro-optical transducer and conducts the optical signal; and

an optical-electro transducer which is connected to the optical fiber to receive the optical signal via the optical fiber and transduces the optical signal into the horizontal and vertical synchronizing signals.

10. A testing apparatus as set forth in claim 6, further comprising:

a transmitter which is connected to the waveform shaping circuit and the frequency divider and modulates a carrier signal by the horizontal and vertical synchronizing signals reproduced, respectively, by the waveform shaping circuit and the frequency divider;

a transmitting antenna which is connected to the transmitter and transmits the modulated carrier signal as radio waves;

a receiving antenna which receives the radio waves transmitted by the transmitting antenna; and

a receiver, connected to the receiving antenna, which demodulates the radio waves received by the receiving antenna and reproduces the horizontal and vertical synchronizing signals.

11. A testing apparatus as set forth in claim 10, wherein the radio wave receiving means is also the receiving antenna.

12. A testing apparatus as set forth in claim 1, further comprising:

image pattern storing means for storing a predetermined image; and

an image pattern comparing means, connected to the image reproducing means and the image pattern storing means, for comparing the reproduced image with the predetermined image and for producing a corresponding information signal when the reproduced image is substantially the same as the predetermined image.

13. A testing apparatus as set forth in claim 12, wherein the information processing system comprises a processor, a display device and a connecting cable which connects tile processor to the display device, and the synchronizing signal receiving means comprises at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable.

14. A testing apparatus as set forth in claim 12, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises:

at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable;

an electro-optical transducer which transduces the horizontal and vertical synchronizing signals received by the at least one cable into an optical signal;

an optical fiber which receives the optical signal from the electro-optical transducer and conducts the optical signal; and

an optical-electro transducer which is connected to the optical fiber to receive the optical signal via the optical fiber and transduces the optical signal into the horizontal and vertical synchronizing signals.

15. A testing apparatus as set forth in claim 12, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises:

at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable;

a transmitter which receives the horizontal and vertical synchronizing signals via the at least one cable and modulates a carrier signal by the horizontal and vertical synchronizing signals;

a transmitting antenna which is connected to the transmitter and transmits the modulated carrier signal as radio waves;

a receiving antenna which receives the radio waves transmitted by the transmitting antenna; and

a receiver, connected to the receiving antenna, which demodulates the radio waves received by the receiving antenna and reproduces the horizontal and vertical synchronizing signals.

16. A testing apparatus for detecting an image from an image signal in radio waves leaking from an information processing system, the information processing system comprising a processor, a display device and a connecting cable which connects the processor to the display device, the processor being a specific model number and operative to use horizontal synchronizing signal and a vertical synchronizing signal to display the image on the display device, the testing apparatus comprising:

radio wave receiving means for receiving the radio waves;

image signal detecting means for detecting the image signal from the received radio waves;

pseudo-synchronizing signal generating means for generating a pseudo horizontal synchronizing signal and a pseudo vertical synchronizing signal respectively having the same periods as the horizontal synchronizing signal and the vertical synchronizing signal the pseudo-synchronizing signal generating means comprising a processor which is the same model number as the processor of the information processing system;

a phase adjuster which is connected to the pseudo-synchronizing signal generating means and adjusts the phase of the pseudo horizontal synchronizing signal and the pseudo vertical synchronizing signal to agree, respectively, with the phases of the horizontal synchronizing signal and the vertical synchronizing signal;

image reproducing means for receiving the adjusted pseudo horizontal synchronizing signal and the adjusted pseudo vertical synchronizing signal and for reproducing the image from the detected image signal by using the adjusted pseudo horizontal synchronizing signal and the adjusted pseudo vertical synchronizing signal;

and

display means for receiving the reproduced image and for displaying the reproduced image.

17. A testing apparatus as set forth in claim 16, wherein the processor of the information processing system and the processor of the pseudo-synchronizing signal generating means are both made by the same manufacturer.

18. A testing apparatus for detecting an image from an image signal in radio waves leaking from an information processing system, the information processing system using horizontal and vertical synchronizing signals to display the image, the testing apparatus comprising:

radio wave receiving means for receiving the radio waves;

image signal detecting means for detecting the image signal from the received radio waves;

synchronizing signal receiving means for receiving the horizontal and vertical synchronizing signals from the information processing system;

image reproducing means for reproducing the image from the detected image signal by using the received horizontal and vertical synchronizing signals; and

display means for displaying the reproduced image, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable.

19. A testing apparatus for detecting an image from an image signal in radio waves leaking from an information processing system, the information processing system using horizontal and vertical synchronizing signals to display the image, the testing apparatus comprising:

radio wave receiving means for receiving the radio waves;

image signal detecting means for detecting the image signal from the received radio waves;

synchronizing signal receiving means for receiving the horizontal and vertical synchronizing signals from the information processing system;

image reproducing means for reproducing the image from the detected image signal by using the received horizontal and vertical synchronizing signals; and

display means for displaying the reproduced image, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises

at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable,

an electro-optical transducer which is connected to the at least one cable to receive the horizontal and vertical synchronizing signals from the at least one cable and transduces the horizontal and vertical synchronizing signals into an optical signal,

an optical fiber which receives the optical signal from the electro-optical transducer and conducts the optical signal, and

an optical-electro transducer which is connected to the optical fiber to receive the optical signal via the optical fiber and transduces the optical signal into the horizontal and vertical synchronizing signals.

20. A testing apparatus for detecting an image from an image signal in radio waves leaking from an information processing system, the information processing system using horizontal and vertical synchronizing signals to display the image, the testing apparatus comprising:

radio wave receiving means for receiving the radio waves;

image signal detecting means for detecting the image signal from the received radio waves;

synchronizing signal receiving means for receiving the horizontal and vertical synchronizing signals from the information processing system;

image reproducing means for reproducing the image from the detected image signal by using the received horizontal and vertical synchronizing signals; and

display means for displaying the reproduced image, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises

at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable,

a transmitter which receives the horizontal and vertical synchronizing signals via the at least one cable and modulates a carrier signal by the horizontal and vertical synchronizing signals,

a transmitting antenna which is connected to the transmitter and transmits the modulated carrier signal as radio waves,

a receiving antenna which receives the radio waves transmitted by the transmitting antenna, and

a receiver, connected to the receiving antenna, which demodulates the radio waves received by the receiving antenna and reproduces the horizontal and vertical synchronizing signals.

21. A testing apparatus as set forth in claim 20, wherein the radio wave receiving means is also the receiving antenna.

22. A testing apparatus for detecting an image from an image signal in radio waves leaking from an information processing system, the information processing system using horizontal and vertical synchronizing signals to display the image, the testing apparatus comprising:

radio wave receiving means for receiving the radio waves;

image signal detecting means for detecting the image signal from the received radio waves;

synchronizing signal receiving means for receiving the horizontal and vertical synchronizing signals from the information processing system;

image reproducing means for reproducing the image from the detected image signal by using the received horizontal and vertical synchronizing signals; and

display means for displaying the reproduced image, wherein the display means generates a magnetic field and the synchronizing signal receiving means comprises

a magnetic sensor which senses the magnetic field generated by the display means and converts the strength of the magnetic field into an electrical signal,

a waveform shaping circuit which shapes the waveform of the electrical signal to reproduce the horizontal synchronizing signal, and

a frequency divider which divides the horizontal synchronizing signal reproduced by the waveform shaping circuit to reproduce a vertical synchronizing signal.

23. A testing apparatus as set forth in claim 22, wherein the waveform shaping circuit comprises an amplifier and an analog-to-digital converter.

24. A testing apparatus as set forth in claim 22, wherein the frequency divider comprises a programmable down counter and a digital switch.

25. A testing apparatus as set forth in claim 22, further comprising:

an electro-optical transducer which is connected to the waveform shaping circuit and the frequency divider and transduces the horizontal and vertical synchronizing signals reproduced, respectively, by the waveform shaping circuit and the frequency divider into an optical signal;

an optical fiber which receives the optical signal from the electro-optical transducer and conducts the optical signal; and

an optical-electro transducer which is connected to the optical fiber to receive the optical signal via the optical fiber and transduces the optical signal into the horizontal and vertical synchronizing signals.

26. A testing apparatus as set forth in claim 22, further comprising:

a transmitter which is connected to the waveform shaping circuit and the frequency divider and modulates a carrier signal by the horizontal and vertical synchronizing signals reproduced, respectively, by the waveform shaping circuit and the frequency divider;

a transmitting antenna which is connected to the transmitter and transmits the modulated carrier signal as radio waves;

a receiving antenna which receives the radio waves transmitted by the transmitting antenna; and

a receiver, connected to the receiving antenna, which demodulates the radio waves received by the receiving antenna and reproduces the horizontal and vertical synchronizing signals.

27. A testing apparatus as set forth in claim 26, wherein the radio wave receiving means is also the receiving antenna.

28. A testing apparatus for detecting an image from an image signal in radio waves leaking from an information processing system, the information processing system using horizontal and vertical synchronizing signals to display the image, the testing apparatus comprising:

radio wave receiving means for receiving the radio waves;

image signal detecting means for detecting the image signal from the received radio waves;

synchronizing signal receiving means for receiving the horizontal and vertical synchronizing signals from the information processing system;

image reproducing means for reproducing the image from the detected image signal by using the received horizontal and vertical synchronizing signals;

display means for displaying the reproduced image;

image pattern storing means for storing a predetermined image; and

an image pattern comparing means, connected to the image reproducing means and the image pattern storing means, for comparing the reproduced image with the predetermined image and for producing a corresponding information signal when the reproduced image is substantially the same as the predetermined image.

29. A testing apparatus as set forth in claim 28, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable.

30. A testing apparatus as set forth in claim 28, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises:

at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable;

an electro-optical transducer which transduces the horizontal and vertical synchronizing signals received by the at least one cable into an optical signal;

an optical fiber which receives the optical signal from the electro-optical transducer and conducts the optical signal; and

an optical-electro transducer which is connected to the optical fiber to receive the optical signal via the optical fiber and transduces the optical signal into the horizontal and vertical synchronizing signals.

31. A testing apparatus as set forth in claim 28, wherein the information processing system comprises a processor, a display device and a connecting cable which connects the processor to the display device, and the synchronizing signal receiving means comprises:

at least one cable which is bifurcated from the connecting cable of the information processing system and receives the horizontal and vertical synchronizing signals from the connecting cable;

a transmitter which receives the horizontal and vertical synchronizing signals via the at least one cable and modulates a carrier signal by the horizontal and vertical synchronizing signals;

a transmitting antenna which is connected to the transmitter and transmits the modulated carrier signal as radio waves;

a receiving antenna which receives the radio waves transmitted by the transmitting antenna; and

a receiver, connected to the receiving antenna, which demodulates the radio waves received by the receiving antenna and reproduces the horizontal and vertical synchronizing signals.