Measuring system

• US 9,377,348 B2
• Filed: 06/12/2013
• Issued: 06/28/2016
• Est. Priority Date: 06/15/2012
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kataoka, Kenichi
• Primary Examiner(s): SAINT SURIN, JACQUES M
• Application Number:
  US13/916,128
• Publication Number:
  US 20130333477A1
• Time in Patent Office: 1,112 Days
• Field of Search: 736/55
• US Class Current: 1/1
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61B 34/30 Surgical robots
• CPC Class Codes: A61B 5/0042 for the brain
• CPC Class Codes: A61B 5/0046 Arrangements of imaging apparatus in a room, e.g. room provided with shielding or for improved access to apparatus
• CPC Class Codes: A61B 5/0051 by applying vibrations
• CPC Class Codes: A61B 5/055 involving electronic [EMR] or nuclear [NMR] magnetic resonance, e.g. magnetic resonance imaging
• CPC Class Codes: A61B 5/245 specially adapted for magnetoencephalographic [MEG] signals
• CPC Class Codes: A61B 5/7217 of noise originating from a therapeutic or surgical apparatus, e.g. from a pacemaker
• CPC Class Codes: G01H 9/00 Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves by using radiation-sensitive means, e.g. optical means
• CPC Class Codes: G01R 33/285 Invasive instruments, e.g. catheters or biopsy needles, specially adapted for tracking, guiding or visualization by NMR
• CPC Class Codes: G01R 33/565 Correction of image distortions, e.g. due to magnetic field inhomogeneities
• CPC Class Codes: H02N 2/142 Small signal circuits; Means for controlling position or derived quantities, e.g. speed, torque, starting, stopping, reversing
• CPC Class Codes: H02N 2/147 Multi-phase circuits
• CPC Class Codes: H02N 2/163 Motors with ring stator

Abstract

A measuring system for measuring a physical quantity related to one of an electromagnetic wave and a magnetic field includes a vibration-type actuator, a waveform generating unit configured to generate a driving waveform signal of the vibration-type actuator, an optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into an optical signal, an optical receiver unit configured to receive the optical signal and convert the optical signal into an alternating-current voltage signal, and a drive circuit configured to receive the alternating-current voltage signal and apply the alternating-current voltage signal to the vibration-type actuator. The waveform generating unit and the optical transmitter unit are disposed outside a magnetic shield room. The optical receiver unit, the drive circuit, and the vibration-type actuator are disposed inside the magnetic shield room, and the optical signal is transmitted between the optical transmitter unit and the optical receiver unit.

Claims

1. A measuring system for measuring a physical quantity related to one of an electromagnetic wave and a magnetic field comprising:

a vibration-type actuator;

a waveform generating unit configured to generate a driving waveform signal of the vibration-type actuator;

an optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into an optical signal;

an optical receiver unit configured to receive the optical signal and convert the optical signal into an alternating-current voltage signal; and

a drive circuit configured to receive the alternating-current voltage signal and output a drive voltage to be applied to the vibration-type actuator,

wherein the waveform generating unit and the optical transmitter unit are disposed outside a magnetic shield room, the optical receiver unit, the drive circuit, and the vibration-type actuator are disposed inside the magnetic shield room, and the optical signal is transmitted between the optical transmitter unit and the optical receiver unit.

2. The measuring system according to claim 1, further comprising:

an optical combining unit; and

an optical distribution unit,

wherein the waveform generating unit generates a plurality of driving waveform signals, the optical transmitter unit converts each of the driving waveform signals into one of a plurality of optical signals having different wavelengths, the optical combining unit combines the optical signals, and the optical distribution unit separates the combined optical signal by wavelength into the optical signals.

3. The measuring system according to claim 1, further comprising:

an optical waveguide unit configured to transfer the optical signal.

4. The measuring system according to claim 1, wherein the waveform generating unit outputs a pulse signal as the driving waveform signal.

5. The measuring system according to claim 4, wherein the waveform generating unit outputs, as the driving waveform signal, a pulse signal obtained by performing pulse modulation on a sine wave.

6. The measuring system according to claim 4, wherein the drive circuit includes a low-pass filter, and

the drive circuit converts the pulse signal into an analog signal using the low-pass filter.

7. The measuring system according to claim 4, wherein the drive circuit includes a D/A converter, and

the drive circuit converts the pulse signal into an analog signal using the D/A converter.

8. The measuring system according to claim 5, further comprising:

a receiving unit configured to receive an electromagnetic wave from an examinee located inside of the magnetic shield room,

wherein the waveform generating unit outputs a pulse signal obtained by performing one of pulse width modulation and pulse amplitude modulation on a sine wave as the driving waveform signal, and

wherein a frequency that is an integer multiple of a modulation frequency of the pulse signal is not included in a Larmor frequency range.

9. A measuring system for measuring a physical quantity related to one of an electromagnetic wave and a magnetic field comprising:

a vibration-type actuator;

a waveform generating unit configured to generate a driving waveform signal of the vibration-type actuator;

a first optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into a first optical signal;

a first optical receiver unit configured to receive the first optical signal and convert the first optical signal into a first alternating-current voltage signal;

a drive circuit configured to receive the first alternating-current voltage signal and apply the first alternating-current voltage signal to the vibration-type actuator;

a detecting unit configured to detect a drive state of a driven member that is driven by the vibration-type actuator;

a second optical transmitter unit configured to convert a detection signal output from the detecting unit into a second optical signal;

a second optical receiver unit configured to receive the second optical signal and convert the second optical signal into a second alternating-current voltage signal; and

a control unit configured to control at least one of a frequency, a phase, and an amplitude of the driving waveform signal on the basis of the second alternating-current voltage signal,

wherein the waveform generating unit, the first optical transmitter unit, the second optical receiver unit, and the control unit are disposed outside a magnetic shield room,

wherein the first optical receiver unit, the drive circuit, the vibration-type actuator, the detecting unit, and the second optical transmitter unit are disposed inside the magnetic shield room, and

wherein the optical signal is transmitted between the first optical transmitter unit and the first optical receiver unit and between the second optical transmitter unit and the second optical receiver unit.

10. The measuring system according to claim 9, further comprising:

a first optical combining unit;

a first optical distribution unit;

a second optical combining unit; and

a second optical distribution unit,

wherein the waveform generating unit generates a plurality of the driving waveform signals, the first optical transmitter unit converts each of the driving waveform signals into one of a plurality of first optical signals having different wavelengths, the detecting unit outputs a plurality of detection signals, the second optical transmitter unit converts each of the detection signals into one of the second optical signals having different wavelengths, and

wherein the first optical combining unit combines the first optical signals, the first optical distribution unit separates the combined first optical signals by wavelength, the second optical combining unit combines the second optical signals, and the second optical distribution unit separates the combined second optical signals by wavelength.

11. The measuring system according to claim 9, further comprising:

an optical waveguide unit configured to transmit the first and second optical signals.

12. The measuring system according to claim 11, wherein the first and second optical signals are transmitted using the same optical waveguide unit.

13. The measuring system according to claim 9, wherein the waveform generating unit outputs a pulse signal as the driving waveform signal.

14. The measuring system according to claim 13, wherein the waveform generating unit outputs, as the driving waveform signal, a pulse signal obtained by performing pulse modulation on a sine wave.

15. The measuring system according to claim 13, wherein the drive circuit includes a low-pass filter, and

the drive circuit converts the pulse signal into an analog signal using the low-pass filter.

16. The measuring system according to claim 13, wherein the drive circuit includes a D/A converter, and

the drive circuit converts the pulse signal into an analog signal using the D/A converter.

17. The measuring system according to claim 9, wherein the detecting unit outputs, as the detection signal, a pulse signal obtained by performing pulse modulation on a sine wave, the second optical transmitter unit converts the pulse signal output from the detecting unit into the second optical signal,

the second optical receiver unit outputs a pulse signal as the second alternating-current voltage signal, and

the control unit obtains a waveform of a sine wave of the detection signal on the basis of the second alternating-current voltage signal and obtains the drive state.

18. The measuring system according to claim 14, further comprising:

a receiving unit configured to receive an electromagnetic wave from an examinee located inside of the magnetic shield room,

wherein the waveform generating unit outputs, as the driving waveform signal, a pulse signal obtained by performing one of pulse width modulation and pulse amplitude modulation on a sine wave, and

wherein a frequency that is an integer multiple of a modulation frequency of the pulse signal is not included in a Larmor frequency range.

19. A system comprising:

a vibration-type actuator;

a waveform generating unit configured to generate a driving waveform signal transmitting a waveform of a drive voltage to be applied to the vibration-type actuator;

an optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into an optical signal;

an optical receiver unit configured to receive the optical signal and convert the optical signal into an alternating-current voltage signal; and

a drive circuit configured to receive the alternating-current voltage signal and output the drive voltage to be applied to the vibration-type actuator.

20. A system comprising:

a vibration-type actuator;

a waveform generating unit configured to generate a driving waveform signal transmitting a waveform of a drive voltage to be applied to the vibration-type actuator;

a first optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into a first optical signal;

a first optical receiver unit configured to receive the first optical signal and convert the first optical signal into a first alternating-current voltage signal;

a drive circuit configured to receive the first alternating-current voltage signal and apply the first alternating-current voltage signal to the vibration-type actuator;

a detecting unit configured to detect a drive state of a driven member that is driven by the vibration-type actuator;

a second optical transmitter unit configured to convert a detection signal output from the detecting unit into a second optical signal;

a second optical receiver unit configured to receive the second optical signal and convert the second optical signal into a second alternating-current voltage signal; and

a control unit configured to control at least one of a frequency, a phase, and an amplitude of the driving waveform signal on the basis of the second alternating-current voltage signal.

21. A measuring system for measuring a physical quantity related to one of an electromagnetic wave and a magnetic field comprising:

a vibration-type actuator;

a waveform generating unit configured to generate a driving waveform signal transmitting a waveform of a drive voltage to be applied to the vibration-type actuator;

an optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into an optical signal;

an optical receiver unit configured to receive the optical signal and convert the optical signal into an alternating-current voltage signal; and

a drive circuit configured to receive the alternating-current voltage signal and output the drive voltage to be applied to the vibration-type actuator,

wherein the waveform generating unit and the optical transmitter unit are disposed outside a magnetic shield room, the optical receiver unit, the drive circuit, and the vibration-type actuator are disposed inside the magnetic shield room, and the optical signal is transmitted between the optical transmitter unit and the optical receiver unit.

22. A measuring system for measuring a physical quantity related to one of an electromagnetic wave and a magnetic field comprising:

a vibration-type actuator;

a waveform generating unit configured to generate a driving waveform signal transmitting a waveform of a drive voltage to be applied to the vibration-type actuator;

a first optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into a first optical signal;

a first optical receiver unit configured to receive the first optical signal and convert the first optical signal into a first alternating-current voltage signal;

a drive circuit configured to receive the first alternating-current voltage signal and apply the first alternating-current voltage signal to the vibration-type actuator;

a detecting unit configured to detect a drive state of a driven member that is driven by the vibration-type actuator;

a second optical transmitter unit configured to convert a detection signal output from the detecting unit into a second optical signal;

a second optical receiver unit configured to receive the second optical signal and convert the second optical signal into a second alternating-current voltage signal; and

a control unit configured to control at least one of a frequency, a phase, and an amplitude of the driving waveform signal on the basis of the second alternating-current voltage signal,

wherein the waveform generating unit, the first optical transmitter unit, the second optical receiver unit, and the control unit are disposed outside a magnetic shield room,

wherein the first optical receiver unit, the drive circuit, the vibration-type actuator, the detecting unit, and the second optical transmitter unit are disposed inside the magnetic shield room, and

wherein the optical signal is transmitted between the first optical transmitter unit and the first optical receiver unit and between the second optical transmitter unit and the second optical receiver unit.

23. A system comprising:

a vibration-type actuator;

a waveform generating unit configured to generate a driving waveform signal transmitting a waveform of a drive voltage to be applied to the vibration-type actuator;

an optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into an optical signal;

an optical receiver unit configured to receive the optical signal and convert the optical signal into an alternating-current voltage signal; and

a drive circuit configured to receive the alternating-current voltage signal and output the drive voltage to be applied to the vibration-type actuator,

wherein the waveform generating unit and the optical transmitter unit are disposed outside a magnetic shield room, the optical receiver unit, the drive circuit, and the vibration-type actuator are disposed inside the magnetic shield room, and the optical signal is transmitted between the optical transmitter unit and the optical receiver unit.

24. A system comprising:

a vibration-type actuator;

a waveform generating unit configured to generate a driving waveform signal transmitting a waveform of a drive voltage to be applied to the vibration-type actuator;

a first optical transmitter unit configured to receive the driving waveform signal and convert the driving waveform signal into a first optical signal;

a first optical receiver unit configured to receive the first optical signal and convert the first optical signal into a first alternating-current voltage signal;

a drive circuit configured to receive the first alternating-current voltage signal and apply the first alternating-current voltage signal to the vibration-type actuator;

a detecting unit configured to detect a drive state of a driven member that is driven by the vibration-type actuator;

a second optical transmitter unit configured to convert a detection signal output from the detecting unit into a second optical signal;

a second optical receiver unit configured to receive the second optical signal and convert the second optical signal into a second alternating-current voltage signal; and

a control unit configured to control at least one of a frequency, a phase, and an amplitude of the driving waveform signal on the basis of the second alternating-current voltage signal,

wherein the waveform generating unit, the first optical transmitter unit, the second optical receiver unit, and the control unit are disposed outside a magnetic shield room,

wherein the first optical receiver unit, the drive circuit, the vibration-type actuator, the detecting unit, and the second optical transmitter unit are disposed inside the magnetic shield room, and

wherein the optical signal is transmitted between the first optical transmitter unit and the first optical receiver unit and between the second optical transmitter unit and the second optical receiver unit.