Test Equipment and Portable Test Device

• US 20080097712A1
• Filed: 02/08/2003
• Published: 04/24/2008
• Est. Priority Date: 02/08/2002
• Status: Active Grant

• Current Assignee: Forstgarten International Holding GmbH
• Original Assignee: 3D Diagnostic Imaging, PLC
• Inventors: Bruce, Peter George, Longbottom, Christopher, Christie, Alasdair McCall, Ferrier, Stephen, Pitts, Nigel Berry
• Granted Patent: US 8,359,179 B2
• Time in Patent Office: Days
• US Class Current: 702/77
• CPC Class Codes: A61B 5/0534 for testing vitality of teeth
• CPC Class Codes: A61B 5/7257 using Fourier transforms

Abstract

The present invention relates to an equipment, device (10; 110) and apparatus for applying electrical stimuli to a system and acquiring a system response. According to the present invention there is provided a test equipment such as a portable test device (10; 110) for testing a system, the equipment comprising: signal generation means, signal receiving means, and signal processing means, wherein, in use, the signal generation means generates a signal to be applied to a system to be tested and the signal receiving means receives a response signal of the system, and the generated and response signals undergo processing by the signal processing means so as to provide a measure of a characteristic of the system, wherein further the generated signal comprises a plurality of periodic signals each of different frequency and phase and which are applied to the system simultaneously. The equipment finds particular use in the field of dentistry, but also finds other uses, e.g. in medicine and also in corrosion detection and battery testing.

Claims

1. A dental, clinical, medical or veterinary test equipment for testing a system comprising a subject, the equipment comprising:

signal generation means,

signal receiving means, and

signal processing means,

wherein, in use, the signal generation means generates a signal to be applied to a subject to be tested and the signal receiving means receives a response signal of the subject, and the generated and response signals undergo processing by the signal processing means so as to provide a measure of a characteristic of the subject, wherein further the generated signal comprises a plurality of periodic signals each of different frequency and phase and which are applied to the subject simultaneously.

2. A test equipment as claimed in claim 1, wherein the characteristic of the subject comprises an AC determined characteristic selected from imittence, impedance, admittance, permittivity or electronic modulus.

3. A test equipment as claimed in claim 1, wherein the signal generation means comprises a signal assembly unit that is software controllable and operates at least in one mode according to an algorithm:

$E_k=a_o<br><br>\underset{i=1}{\overset{n}{\sum <br><br>}}<br><br>\sin <br><br>\left(2<br><br><br><br>\mathrm{\pi <br><br>}<br><br><br><br>i<br><br><br><br>f_0<br><br>t_k+{\mathrm{\theta <br><br>}}_i\right)$

where E_k=voltage at any given time t_k,

θ

_i=phase randomised for each periodic signal so as to provide the plurality of periodic output signals.

4. A test equipment as claimed in claim 1, wherein each of the plurality of periodic signals optionally comprises a sine wave, and the signal processing means performs a Fast Fourier Transform (FFT) analysis on the generated and response signals.

5. A test equipment as claimed in claim 1, wherein the phase of each of the plurality of periodic signals generated by the signal generation means is random.

6. A test equipment as claimed in claim 1, wherein one of the periodic signals has a frequency f_o, and each other periodic signal has a frequency which is a multiple of frequency f_o.

7. A test equipment as claimed in claim 6, wherein the generated signal is applied to the system for a period of time comprising at least 1/f_o or a multiple of 1/f_o.

8. A test equipment as claimed in claim 1, wherein each point k of the generated signal is given by:

$E_k=a_o<br><br>\underset{i=1}{\overset{n}{\sum <br><br>}}<br><br>\sin <br><br>\left(2<br><br><br><br>\mathrm{\pi <br><br>}<br><br><br><br>i<br><br><br><br>f_0<br><br>t_k+{\mathrm{\theta <br><br>}}_i\right)$

where E_k=voltage at any given time t_k,

θ

_i=phase randomised for each periodic signal.

9. A test equipment as claimed in claim 1, wherein there are provided means to control the signal generation means.

10. A test equipment as claimed in claim 9, wherein the means to control the signal generation means allows a user to select, switch or program the signal generation means to operate in a different mode to generate a different electrical signal, optionally selected from at least one or more of a single signal, a DC signal or a periodic signal such as a single sine wave or swept sine wave.

11. A test equipment as claimed in claim 1, wherein the test equipment is portable.

12. A test equipment as claimed in claim 1, wherein the test equipment comprises a portable test device, and wherein the signal generation means, signal receiving means and signal processing means are provided within a common casing.

13. A test equipment as claimed in claim 1, wherein the test equipment comprises a computer means providing the signal processing means, and a module including the signal generation means and/or the signal receiving means, the computer means and the module being separate/separable one from the other.

14. A test equipment as claimed in claim 13, wherein the test equipment also includes an isolation unit to electrically isolate the patient from the module and/or computer means, in use.

15. A test equipment as claimed in claim 13, wherein there are provided means for electrically connecting or electrically docking the computer means and the module one to the other.

16. A test equipment as claimed in claim 13, wherein the computer means comprises a notebook or laptop PC.

17. A dental, clinical, medical or veterinary test apparatus such as a portable test apparatus for testing a system comprising a subject, the apparatus comprising:

a test equipment according to claim 1;

electrode means which, in use, apply the generated signal to the subject and receive the response signal from the subject.

18. A test equipment as claimed in claim 17, wherein the electrode means are, in use, applied to the system in a non-invasive and non-destructive manner.

31. Use of a test apparatus such as a portable test apparatus in the detection of dental states or conditions such as dental caries, the apparatus comprising:

a test equipment according to claim 1;

electrode means which, in use, apply the generated signal to the tooth and receive the response signal from the tooth.

32. Use of a test apparatus such as a portable test apparatus in the detection of medical states or conditions, the apparatus comprising:

a test equipment according to claim 1;

electrode means which, in use, apply the generated signal to the medical system and receive the response signal from the system.

33. Use of a test apparatus such as a portable test apparatus in the detection of a state or condition of a non-dental/non-medical system, the apparatus comprising:

a test equipment according to claim 1;

electrode means which, in use, apply the generated signal to the system and receive the response signal from the system.

34. Use of a test apparatus as claimed in claim 31, wherein the electrode means are, in use, applied to the tooth in a non-invasive and non-destructive manner.

35. A method of detecting dental states or conditions such as dental caries comprising the steps of:

providing a test apparatus according to claim 17;

generating an electrical signal and applying said electrical signal to a tooth;

detecting a response electrical signal; and

processing the generated and response signals so as to provide a measure of a characteristic of the tooth.

36. A method of detecting medical states or conditions comprising the steps of:

providing a test equipment according to claim 17;

generating an electrical signal and applying said electrical signal to a medical system;

detecting a response electrical signal;

processing the generated and response signals so as to provide a measure of a characteristic of the system.

37. A method of detecting a state or condition of a non-dental/non-medical system comprising the steps of:

providing a test equipment according to claim 17;

generating an electrical signal and applying said electrical signal to a system;

detecting a response electrical signal;

processing the generated and response signals so as to provide a measure of a characteristic of the system.

51. A portable test device as claimed in claim 13, wherein the device is provided with one input/output port wherein the device cannot be connected to an external power supply and a system to be tested simultaneously.

57. A portable test device as claimed in claim 13, wherein the applied signal is of a single frequency.

60. A test equipment or portable test device as claimed in claim 1, wherein the signal processing means or means for analysing the applied signal and received signal performs Fast Fourier Transform (FFT) spectrum analysis upon the applied signal and received signal.

61. A test equipment or portable test device as claimed in claim 1, wherein the equipment device is adapted for use detecting a dental or medical condition in vivo in a system comprising at least in part biological materials or tissues, e.g. at least part of a human or animal body.

62. A test equipment or portable test device as claimed in claim 1, wherein the equipment or device is adapted for use with a system selected from a battery, fuel cell or the like.

63. A test equipment or portable test device as claimed in claim 1, wherein the equipment or device is adapted for use in detecting corrosion or the condition of coatings such as paints and polymers using non-destructive testing techniques.

64. A test equipment or portable device as claimed in claim 1, wherein tests carried out using the equipment or device generating a signal having a frequency in the range of DC-100 kHz provide results for measurements made involving systems characterised by low frequency response such as polymers, dielectrics and electrode processes or other high impedance media.

65. A test equipment or portable test device as claimed in claim 1, wherein tests performed using the equipment or device generating a signal in a range above 100 kHz provides results for measurements made involving systems characterised by high frequency response such as highly conducting electrolytes or other low impedance media.

113. A test equipment as claimed in claim 1, wherein the test equipment comprises a port which can be used as a link to other devices to allow wireless data transfer or printing.

114. A test equipment as claimed in claim 1, wherein the test equipment comprises a battery(ies).

115. A test equipment as claimed in claim 1, wherein there is provided an inductive charging unit to wirelessly recharge the battery(ies).

19. Use of a test equipment such as a portable test equipment or device in the detection of dental states or conditions such as dental caries, the equipment comprising:

signal generation means,

signal receiving means, and

signal processing means, wherein, in use, the signal generation means generates a signal to be applied to a tooth to be tested and the signal receiving means receives a response signal of the tooth, and the generated and response signals undergo processing by the signal processing means so as to provide a measure of a characteristic of the tooth, wherein further the generated signal comprises a plurality of periodic signals each of different frequency and phase and which are applied to the tooth simultaneously.

22. Use of a test equipment as claimed in claim 19, wherein the characteristic of the tooth comprises an AC determined characteristic selected from imittance, impedance, admittance, permittivity or electric modulus.

23. Use of a test equipment as claimed in claim 19, wherein the signal generation means comprises a signal assembly unit that is controllable by software and operates at least in one mode according to an algorithm:

$E_k=a_o<br><br>\underset{i=1}{\overset{n}{\sum <br><br>}}<br><br>\sin <br><br>\left(2<br><br><br><br>\mathrm{\pi <br><br>}<br><br><br><br>i<br><br><br><br>f_0<br><br>t_k+{\mathrm{\theta <br><br>}}_i\right)$

where E_k=voltage at any given time t_k,

θ

_i=phase randomised for each periodic signal so as to provide the plurality of periodic output signals.

24. Use of a test equipment as claimed in claim 19, wherein each of the plurality of periodic signals optionally a sine wave, and the signal processing means performs a Fast Fourier Transform (FFT) analysis on the generated and response signals.

25. Use of a test equipment as claimed in claim 19, wherein the phase of each of the plurality of periodic signals generated by the signal generation means is random.

26. Use of a test equipment as claimed in claim 19, wherein one of the periodic signals has a frequency f_o, and each other periodic signal has a frequency which is a multiple of frequency f_o.

27. Use of a test equipment as claimed in claim 26, wherein the generated signal is applied to the tooth for a period of time comprising at least 1/f_o or a multiple of 1/f_o.

28. Use of a test equipment as claimed in claim 19, wherein each point k of the generated signal given by:

$E_k=a_o<br><br>\underset{i=1}{\overset{n}{\sum <br><br>}}<br><br>\sin <br><br>\left(2<br><br><br><br>\mathrm{\pi <br><br>}<br><br><br><br>i<br><br><br><br>f_0<br><br>t_k+{\mathrm{\theta <br><br>}}_i\right)$

where E_k=voltage at any given time t_k,

θ

_i=phase randomised for each periodic signal.

29. Use of a test equipment as claimed in claim 19, wherein there are provided means to control the signal generation means.

30. Use of a test equipment as claimed in claim 29, wherein the means to control the signal generation means allows a user to select, switch or program the signal generation means to operate in a different mode to generate a different electrical signal optionally selected from at least one or more of a single signal, a DC signal, or periodic signal such as a single sine wave or swept sine wave.

20. Use of a test equipment such as a portable test equipment or device in the detection of medical states or conditions the equipment comprising:

signal generation means,

signal receiving means, and

signal processing means, signal to be applied to a medical system to be tested and the signal receiving means receives a response signal of the system, and the generated and response signals undergo processing by the signal processing means so as to provide a measure of a characteristic of the system, wherein further the generated signal comprises a plurality of periodic signals each of different frequency and phase and which are applied to the system simultaneously.

21. Use of a test equipment such as a portable test equipment or device in the detection of a state or condition of a non-dental/non-medical system such as a metal, metal coating or a battery, the equipment comprising:

signal generation means,

signal receiving means, and

signal processing means,

wherein, in use, the signal generation means generates a signal to be applied to a system to be tested and the signal receiving means receives a response signal of the system, and the generated and response signals undergo processing by the signal processing means so as to provide a measure of a characteristic of the system, wherein further the generated signal comprises a plurality of periodic signals each of different frequency and phase and which are applied to the system simultaneously.

38. A dentist'"'"'s chair or light unit providing test equipment or having detachably attached thereto a test device, the equipment or device comprising:

signal generation means,

signal receiving means, and

signal processing means,

wherein, in use, the signal generation means generates a signal to be applied to a tooth to be tested and the signal receiving means receives a response signal of the tooth, and the generated and response signals undergo processing by the signal processing means so as to provide a measure of a characteristic of the tooth, wherein further the generated signal comprises a plurality of periodic signals each of different frequency and phase and which are applied to the tooth simultaneously.

39. A portable test device for generating an electrical signal to be applied to a system and acquiring a response signal generated by the system, the device comprising:

signal generation means,

signal receiving means, and

signal processing means,

wherein, in use, the device generates a signal to be applied to a system to be tested, and receives a response signal of the system which was tested whereby the applied and received signals undergo processing by the signal processing means to provide data.

40. A portable test device as claimed in claim 39, wherein the data is indicative of a system characteristic.

41. A portable test device as claimed in claim 39, wherein the device comprises data storage means to which the data is transferred for storage.

42. A portable test device as claimed in claim 39, wherein the device is hand held.

43. A portable test device as claimed in claim 39, wherein the device includes means for visually displaying data.

44. A portable test device as claimed in claim 39, wherein the device measures an impedance of the system.

45. A portable test device as claimed in claim 39, wherein the device is battery operated.

46. A portable test device as claimed in claim 45, wherein the device comprises means by which the device is removably connectable to a mains power supply to allow charging of the batter(ies) to take place.

47. A portable test device as claimed in claim 39, wherein the device includes means for associating the device with electrode means comprising at least a first electrode and a second electrode, wherein the first electrode applies the generated signal to the system to be tested and the second electrode collates response signals from the system response.

48. A portable test device as claimed in claim 39, wherein the device is configured or arranged such that connection to an external power supply and electrode means cannot occur simultaneously.

49. A portable test device as claimed in claim 39, wherein the device is configured or arranged such that connection to an external power supply and electrode mean can occur simultaneously.

50. A portable test device as claimed in claim 39, wherein the device is provided with safety features adapted for medical electrical equipment.

52. A portable test device as claimed in claim 39, wherein the device is provided with two or more input/output ports wherein power to the device and the signals transferring to and from the device are assigned to individual input/output ports.

53. A portable test device as claimed in claim 39, wherein the signal applied to the system comprises at least one periodic signal such as an AC signal.

54. A portable test device as claimed in claim 39, wherein the applied signal is formed of a plurality of periodic waves such as sine waves.

55. A portable test device as claimed in claim 54, wherein each of the periodic waves such as sine waves is of a different frequency and random phase.

56. A portable test device as claimed in claim 39, wherein the applied signal is a square wave or other waveform.

58. A portable test device as claimed in claim 39, wherein the means for analysing the applied signal and received signal performs Fast Fourier Transform (FFT) spectrum analysis upon the applied signal and received signal.

59. A portable test device as claimed in claim 39, wherein the signal receiving means includes data acquisition means.

66. A portable test device as claimed in claim 39, wherein the device is customised for specific end-use by embedded PC-based control software.

67. A portable test device as claimed in claim 39, wherein the device is programmed to perform a range of measurements with subsequent analysis, presentation, data storage and retrieval.

68. A portable test device as claimed in claim 39, wherein the device further comprises means for performing variable amplification on the received signal.

69. A portable apparatus for applying electrical stimulus to a system and acquiring a system response, the apparatus comprising:

signal generation means,

signal receiving means,

signal processing means, and

electrode means which are, in use, applied to the system, wherein a generated signal is applied to the system by said electrode means, a response signal of the system is detected by said electrode means and received by the signal receiving means, and the applied and received signals undergo processing by the signal processing means.

70. A portable apparatus as claimed in claim 69, wherein data generated by the signal processing means is transferred to data storage means for storage.

71. A portable apparatus as claimed in claim 69, wherein the signal processing means performs signal analysis on the generated or applied signal and response or received signal.

72. A portable apparatus as claimed in claim 69, wherein the electrode means comprises one or more electrodes and optionally comprise an array of electrodes.

73. A portable device for generating an electrical signal to be applied to a system and acquiring a response signal generated by the system, the portable device comprising:

signal generation means,

signal receiving means,

signal processing means, and

a single input/output electrical connection means, wherein optionally the electrical connection means comprises a customised multi-pin plug port which is configured such that each pin is assigned a function so that a plurality of operations can be performed by the device via the port.

74. A portable device as claimed in claim 73, wherein the device further comprise data storage means.

75. A portable device as claimed in claim 73, wherein the plurality of operations performed by the device via the port or single input/output electrical connection means include at least one of charging a battery of the device, transferring data into the device, transferring data out of the device.

76. A portable device as claimed in claim 73, wherein the port is a 12-way port or socket.

77. A portable device for generating an electrical signal to be applied to a system and acquiring a response signal generated by the system, the portable device comprising:

signal generation means,

signal receiving means,

signal processing means, and

selection means;

wherein the selection means are used to select an appropriate signal to be generated the device generates a function to be performed by the device and the appropriate signal to be applied to a system to be tested, and receives a response signal of the system which was tested whereby the applied and received signals undergo processing by the signal processing means to provide data.

78. A portable device as claimed in claim 77, wherein the data provided is transferred to data storage means for storage.

79. A portable device as claimed in claim 77, wherein the device includes means for visually displaying data.

80. A portable device as claimed in claim 77, wherein the selection means is used to select processing steps to be performed by the signal processing means.

81. A portable device as claimed in claim 77, wherein the function of the device selected is such that the device performs electrical or electrochemical measurements in the time domain.

82. A portable device as claimed in claim 77, wherein the function of the device selected is such that the device performs electrical or electrochemical measurements in the frequency domain.

83. A portable device as claimed in claim 77, wherein the generated signal is at least one AC signal.

84. A portable device as claimed in claim 77, wherein the generated signal is a DC signal.

85. A portable device for generating a complex electrical signal to be applied to a system and acquiring a response signal generated by the system, the portable device comprising:

signal generation means,

signal receiving means, and

signal processing means,

wherein the device generates a complex signal to be applied to a system to be tested and receives a response signal of the system which was tested whereby the applied and received signals undergo processing by the signal processing means to provide data indicative of a feature of the system.

86. A portable device as claimed in claim 85, wherein the data provided is transferred to data storage means for storage.

87. A portable device for generating a sequence of predetermined electrical signals to be applied to a system and acquiring a corresponding sequence of response signals generated by the system, the portable device comprising:

signal generation means,

signal receiving means, and

signal processing means,

wherein the device generates a sequence of predetermined signals to be applied to a system to be tested, and receives a corresponding sequence of response signals of the system which was tested whereby the applied and received signals undergo processing by the signal processing means to provide data indicative of a characteristic of the system.

88. A portable device as claimed in claim 87, wherein the data provided is transferred to data storage means for data storage.

89. A portable device for detecting a dental condition by generating an electrical signal to be applied to a system and acquiring a response signal generated by the system, the portable device comprising:

signal generation means,

signal receiving means, and

signal processing means,

wherein, in use, the device generates a signal to be applied to a system to be tested, and receives a response signal of the system which was tested, whereby the applied and received signals undergo processing by the signal processing means to provide data indicative of a characteristic of the system.

90. A portable device as claimed in claim 89, wherein the provided data is transferred to data storage means for storage.

91. A portable device as claimed in claim 89, wherein tests carried out using the device generating a signal(s) having a frequency(ies) in the range of 1 Hz-100 kHz provides results for measurements made involving systems characterised by low frequency response such as high impedance material or dental hard tissue and, for example, abrasion, attrition, caries, erosion or corrosion thereof, or indeed any change in the tissue by any means, eg mechanical or chemical.

92. A portable device as claimed in claim 89, wherein tests performed using the device generating a signal in a range above 100 kHz provides results for measurements made involving systems characterised by high frequency response such as soft tissue or other low impedance media.

93. A portable device for generating an electrical signal to be applied to the system and acquiring a response signal generated by the system, for use in the detection of clinical conditions, the portable device comprising:

signal generation means,

signal receiving means,

signal processing means, and

analogue circuitry, wherein the analogue circuitry includes medical safety features which allows the device to perform tests in in vivo environments wherein the device generates a signal to be applied to a system under test and receives a response signal of the system which was tested whereby the applied and received signals undergo processing by the signal processing means providing data indicative of a characteristic of the system.

94. A portable device as claimed in claim 93, wherein the provided data is transferred to data storage means for storage.

95. A portable device as claimed in claim 93, wherein tests carried out using the device generating a signal(s) having a frequency(ies) in the range of 1 Hz-100 kHz provides results for measurements made involving systems characterised by high frequency response such as bone or other hard tissue including detecting the corrosion or erosion thereof or other high impedance media.

96. A portable device as claimed in claim 93, wherein tests performed using the device generating a signal in a range above 100 kHz provides results for measurements made involving systems characterised by high frequency response such as soft tissues or other low impedance media.

97. A portable device as claimed in claim 93, wherein safety features of the analogue circuitry are adapted for medical electrical equipment.

98. A portable device as claimed in claim 93, wherein the device is provided with only one input/output port such that the device cannot be connected to an external power supply and a system to be tested simultaneously.

99. A portable device as claimed in claim 93, wherein the device is used in vivo to measure or monitor a state of a material used in reconstruction of a body part such as a prosthetic or a metal or synthetic “

pin”

or the like including the corrosion thereof.

100. A portable device for generating an electrical signal to be applied to a system and acquiring a response signal generated by the system, the portable device comprising:

signal generation means,

signal receiving means,

signal processing means, and

electrode means comprising at least a first electrode and a second electrode,

wherein the device generates a signal to be applied via the first electrode to a system to be tested, and receives via the second electrode a response signal of the system which was tested whereby the applied signal and received signal undergo processing by the signal processing means to provide data indicative of a characteristic of the system, the first and second electrodes of the device having been selected for the application and receiving of the signals in a manner which provides data.

101. A portable device as claimed in claim 100, wherein the data provided is transferred to data storage means for storage.

102. A portable device for generating an electrical signal to be applied to a system and acquiring a response signal generated by the system, the portable device comprising:

signal generation means,

signal receiving means,

signal processing means, and

selection means

wherein the device generates the signal to be applied to the system to be tested and receives the response signal of the system which was tested whereby the applied and received signals undergo processing by the signal processing means to provide data indicative of a characteristic of the system, the selection means being used to determine the applied signal and ratio obtained by the device in order to compensate for noise.

103. A portable device as claimed in claim 102, wherein the data provided is transferred to data storage means for storage.

104-112. -112. (canceled)

116. A test equipment for testing a system, the equipment comprising:

signal generation means,

signal receiving means, and

signal processing means,

wherein, in use, the signal generation means generates a signal to be applied to a system to be tested and the signal receiving means receives a response signal of the system, and the generated and response signals undergo processing by the signal processing means so as to provide a measure of a characteristic of the system, wherein further the generated signal comprises a plurality of periodic signals each of different frequency and phase and which are applied to the system simultaneously.