JPS5967942A - Apparatus for ultrasonic scanning of body cavity - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an intrabody cavity ultrasonic scanning device which includes an ultrasonic mirror or an ultrasonic probe rotation angle detection means and which depicts an ultrasonic cross-sectional image.

FIG. 1 is an external view of an intrabody cavity ultrasonic diagnostic apparatus equipped with a conventional intrabody cavity ultrasonic scanning device.

As shown in FIG. 1, the intracorporeal ultrasound diagnostic apparatus includes an endoscope 1, a control processing circuit 2, and a monitor device 3. The endoscope 1 includes a flexible insertion section 4, an observation section 5, and an operation handle 6.
The insertion section 4 has a storage section 7, an illumination window 8, and an observation window 9 at its distal end.

In the intrabody cavity ultrasound diagnostic apparatus configured as described above, an ultrasound probe, an ultrasound reflector, etc. are housed in the housing section 7, and together with the control processing circuit 2, an ultrasound probe in the body cavity is used. configuring the device. Therefore, this housing section 7 is inserted into the body cavity, the ultrasonic beam is radiated and collected, and the control processing circuit 2
By performing image processing at , it becomes possible to display an ultrasonic tomographic image on the monitor device 3.

At this time, it is necessary to detect the rotation angle of the ultrasonic probe or the ultrasonic reflector in order to perform radial scanning. As a well-known technique of this rotation angle detection method, Japanese Patent Application Laid-Open No. 57-52
There is one disclosed in No. 444.

FIG. 2 is a diagram for explaining the above technique, and is an enlarged sectional view showing the internal structure of the distal end of the insertion section 4 in FIG. 1. Hereinafter, the same parts in FIGS. 1 to 14 will be denoted by the same reference numerals, and the description of the parts that have already been explained will be omitted.

In FIG. 2, light from a light source (not shown) passes through the entire light guide 10 and is irradiated into the body cavity from the illumination window 8. Further, the optical image from the observation window 9 can be visually observed from the observation section 5 in FIG. 1 through the entire image guide II.

On the other hand, inside the storage part 7, a cylinder is placed at an angle of 45° with respect to its central axis.
An ultrasonic reflecting mirror 12 having a shape cut in the direction shown in FIG. Further, a rotation angle detection plate 14 is fixed to the rotation shaft 13, and is rotated together with the ultrasonic reflecting mirror 12 by a motor (not shown) via a power transmission member 15 such as a coil wire.

Further, an ultrasonic probe 1 is placed opposite the ultrasonic reflector 12.
6 is provided and guided to the control processing circuit 2 by a conductive wire 17 connected to a part thereof. fclB
is made of balloon rubber made of organic resin or the like, and is crimped to the outer wall of the insertion portion 4 by a ring 19 at its opening. This balloon rubber 18 is filled with an ultrasonic transmission medium 20 such as oil or water.

In the intrabody cavity ultrasonic scanning device configured as described above, the rotational driving force given by the motor (not shown) is transmitted to the power transmission member 1.
The ultrasonic reflecting mirror 12 is rotationally driven through the mirror 5. The high frequency noculus guided from the control processing circuit 2 via the conductor 17 is converted into an ultrasonic beam by the ultrasonic probe 16, passes through the ultrasonic transmission medium 20, and is directed to the ultrasonic reflecting mirror I2.
corresponds to Further, the direction of this ultrasonic beam is changed by 90°, and as the ultrasonic reflecting mirror 12 rotates, it is continuously radiated inside the body in the radial direction. The ultrasonic echo signal reflected from the object inside the body is reflected again by the ultrasonic reflector 12 and collected by the ultrasonic probe 16 again. Thus, the ultrasonic probe 16 converts the ultrasonic echo signal into an electric signal and sends it to the control processing circuit 2 via the conductor 17, thereby rendering an ultrasonic tomographic image on the monitor device 3.

FIG. 3 is a perspective view showing only the rotation angle detection mechanism comprised of the ultrasonic reflecting mirror 12, rotation angle detection plate 14, etc. in FIG. 2.

In FIG. 3, the rotation angle detection plate 14 has its detection surface 24a.
is formed in a tenon shape with respect to the direction of rotation, and an optical fiber 21. is formed opposite to this detection surface 24a.
22 are arranged in parallel. These optical fibers 2
A light emitting element 23 and a light receiving element 2 are installed at one end of 1.22, respectively.
4 is connected. Therefore, the light emitted from the light emitting element 23 passes through the optical fiber 21 and is irradiated toward the detection surface 14m of the rotation angle detection plate 14. Furthermore, the light reflected by the detection surface 14h is transferred to the optical fiber 2.
2 and enters the light receiving element 24.

On the other hand, as described above, the detection surface 14a of the rotation angle detection plate I4
is formed in a tapered shape with respect to the rotation direction, so when the rotation angle detection plate 14 is rotated, the output end surface of the optical fiber 21 and the input end surface of the optical fiber 22 are aligned with the groove 4 and the detection surface. The distance between 24m and 24m changes continuously. As a result, the amount of light incident on the light receiving element 24 also changes, so the light receiving element 24 transmits an output voltage to the control processing circuit 2 according to the rotation angle of the rotation angle detection plate, that is, the rotation angle of the ultrasonic reflecting mirror 12. It turns out. Note that 25 is a motor that rotationally drives the ultrasonic reflecting mirror 12 via a power transmission member I5.

FIG. 4 shows a block diagram of the control processing circuit 2 and the monitor device 3.

In FIG. 4, the motor 25 is driven to rotate at a constant speed by a motor drive power source 30. In FIG. The rotation angle of the rotation angle detection plate 14 rotationally driven by the motor 25 is determined by the light emitting element 23, the light receiving element 24, and the optical fiber 21.2.
It is detected by a rotation angle detector 31 having a rotation angle θ, and becomes a signal corresponding to the rotation angle θ of the ultrasonic reflecting mirror 12.

This signal is supplied to the self-question generation circuit 32 and the cos function generation circuit 33, and becomes a signal converted into blood θ and cos θ.

On the other hand, the output signal of the rotation angle detector 31 is also supplied to the comparison circuit 35 of the ultrasonic wave transmission/reception signal processing circuit 34, and when the rotation angle of the ultrasonic reflector 12 exceeds a certain angle θ0, a trigger pulse for the next stage is generated. An output signal is sent to circuit 36. This signal is converted into a trigger pulse by the trigger pulse generation circuit 36 and is supplied to the sawtooth wave generation circuit 37.

The sawtooth wave generated here and the image θ and cos
The θ signal is supplied to a sweep signal generation circuit 38 composed of a multiplier and the like, and is converted into an X deflection signal and an X deflection signal for the monitor device 3 via an amplifier 39.

On the other hand, the trigger pulse generated by the trigger pulse generation circuit 36 is also supplied to the high frequency pulse generation circuit 40. The high frequency pulse generated by the high frequency pulse generating circuit 40 is amplified by an amplifier 41 and then supplied to the ultrasound probe 16. The ultrasonic probe 16 irradiates ultrasonic waves into the human body using this high frequency wave, and further converts reflected and returned ultrasonic echo signals into electrical signals. This signal is detected by a detection circuit 42, amplified by an amplifier 43, and then supplied to the monitor device 3 as a biaxial, ie, brightness modulated signal. In this way, a radially scanned sector-shaped ultrasonic tomographic image is displayed on the monitor device 1≦7.

In the conventional intrabody cavity ultrasonic scanning device having the above configuration, the rotation angle detection method of the ultrasonic reflecting mirror 12 is based on photoelectric conversion. The detected value varies depending on the relative position. Therefore, high precision is required when these rotational angle detection mechanisms are installed in the apparatus, and additional noise will be generated if the detection surface 14a of the rotational angle detection plate I4 is not sufficiently uniform. As a result, there was a problem that the device itself became complicated. Furthermore, since the rotation angle detection plate 14 is used as described above, there is a problem that the apparatus cannot be made into a shed. In addition, there is a problem in that the accuracy of detecting the rotation angle is low, resulting in blurred images and blurred images.

The present invention was made based on these problems, and its purpose is to provide a clear image and simplify the device itself by detecting the rotation angle of an ultrasonic reflector or an ultrasonic probe with high precision. Another object of the present invention is to provide a miniaturized intrabody cavity ultrasonic scanning device.

In order to achieve the above-mentioned object, the present invention generates a noise by sliding a plurality of dielectric bits disposed on the cylindrical bottom or side surface of an ultrasonic reflector or an ultrasonic probe on a slider. The present invention is characterized in that the change in capacitance of the ultrasonic reflector or the ultrasonic probe is detected as a digital quantity, thereby improving the rotation angle detection accuracy.

DESCRIPTION OF THE PREFERRED EMBODIMENTS An intrabody cavity ultrasonic scanning device, which is an embodiment of the present invention, will be described below with reference to FIGS. 5 to 12.

FIG. 5 is a sectional view showing the internal structure at the distal end of the insertion section of the intrabody cavity ultrasound diagnostic apparatus using the intrabody cavity ultrasound scanning apparatus of this embodiment.

The difference in FIG. 5 from FIG. 2 is that the rotation angle detection plate 1
4 is removed, and a bright ultrasonic reflecting mirror 51 is used, in which a bit array 50 having a plurality of concave and convex portions is provided on the cylindrical bottom surface of the ultrasonic reflecting mirror 12.

Fig. 6 is a perspective view of this ultrasonic reflecting mirror 51, Fig. 7 (=)
(b) shows a front view and a side view of the same, FIG. 8 shows an enlarged perspective view of the slider 52 shown in FIG. 5, and FIG. 9 shows the sliding state of the bit string 50 and the slider 52. Figures are shown respectively.

As shown in FIGS. 6 and 7(a) and (b), a ground electrode 5, which is a first electrode, is attached to the bottom of the cylinder of the ultrasonic reflector 510.
A bit string 50 having a plurality of concavities and convexities is provided through 3f. The material of the ground electrode 53 is aluminum or tantalum, and is fixed on the end surface of the ultrasonic mirror 50 by a method such as vapor deposition or sputtering. This ground electrode 53 is grounded through a rotating shaft 54 and a bearing portion 55 in FIG. Further, the bit string 50
is made of a dielectric material such as polystyrene, and is made into a polymer by glow discharge in a vacuum to make the surface stronger. Note that the bit string 50 may be made of alumite. Further, as shown in FIG. 7(a), one pit 50a of the bit string 50 has a longer length in the circumferential direction than other pits.

FIG. 8 is an enlarged perspective view of the slider 52. The width 522L is a wire made of a good conductor such as phosphor bronze, and is connected to a control processing circuit (not shown) by a conductive wire. Also, 52b
is sapphire (At2o3).

The electrode protection material 52c, such as diamond, has such a shape and size that it cannot be fixed to the electrode protection material 52b by sputtering or the like. The sliding state of the slider 52 and the bit string 50 is as shown in FIG.

FIG. 10 shows a new control processing circuit 56 and monitor device 3 for detecting the rotation angle from the ultrasonic reflecting mirror 51 and slider 52 configured as described above, and depicting an ultrasonic tomographic image on the monitor device 3. It is a block diagram.

Now, when the ultrasonic reflecting mirror 51 is rotated, each pit of the bit string 50 and the slider 52 slide.
The capacitance between the electrode 52c of the slider 52 and the ground electrode 53 changes in accordance with the change in the depth of the pit. This situation can be considered equivalent to the variable capacitor 60 in FIG. Therefore, a coil 61 is connected in parallel with this variable capacitance capacitor to form a resonant circuit. In this resonant circuit, the resonant frequency changes alternately between fx and fz in response to the above-mentioned change in capacitance.

Furthermore, this resonance frequency f! and fz is also a high frequency f
.

The output of a high frequency oscillator 62 which oscillates at is applied to the resonant circuit.

FIG. 11 is a diagram showing the frequency characteristics of Koi A/610 at this time.

As is clear from FIG. 11, the resonance frequency J'l
, fz, the amplitude of the resonant circuit also changes A I
+A2.

Furthermore, in FIG. 10, the output of this resonant circuit is amplified by an amplifier 63 and full-wave rectified by a detection circuit 64.

This full-wave rectified signal is subjected to low-frequency extraction by a rotor or filter 5, and further converted into a binary rectangular wave by a comparator 66.

FIG. 12 is a waveform diagram for explaining the above process, in which A is the output waveform of the amplifier circuit 63, B is the output waveform of the detection circuit 64, and C is the output waveform of the low-pass filter 65. , respectively show the output waveforms of the Did comparator 66 in the figure.

On the other hand, as explained with reference to FIG. 7, one pit 50g of the bit string 50 is formed to have a longer length in the circumferential direction than the other pits. Therefore, this pit 501L is the electrode 52
Only during the period when the comparator 66 is sliding with respect to J? The width of the loop is also wider. For this reason, the above-mentioned pulse is used as a staft noculus and is distinguished from other noculus.

Returning to FIG. 10 again, an explanation will be added.

In FIG. 10, when the above-mentioned start pulse from the comparator 66 is input to the retrig pull-marteno repeater 7 (hereinafter simply abbreviated as RMV), the RMV 67
RMV 67 because no retrigger is applied during the metastable period of
The output of is inverted. Therefore, this becomes a reset signal and is output to scan converter 68.

On the other hand, a transmitting circuit 69 having a high frequency oscillator and an amplifier circuit #
sends out a high frequency noculus to the ultrasonic probe 16. This high frequency pulse is converted into an ultrasonic beam by the ultrasonic probe I6, and is emitted in the radial direction as the ultrasonic reflecting mirror 51 rotates. Furthermore, the ultrasonic echo signal reflected from the object inside the body is collected again by the ultrasonic probe I6 and converted into an electrical signal. This signal is logarithmically amplified by a logarithmic compression amplifier 70 and detected by a detection circuit 71. Furthermore, this detected signal is processed by a signal processing circuit 72 as an STC (Sens
time control).

AG C (Automatic Galn Conto)
rol) etc., and the scan converter 6
8. The scan converter 68 is triggered by the reset signal and outputs a video signal to the next stage synchronous separation circuit 73, and also sends this video signal to the monitor R3 as a biaxial brightness modulation signal. The synchronization signal separated by the synchronization separation circuit 73 is supplied to the monitor device 3 as an X-axis deflection signal and a Y-axis deflection signal by a sweep signal generation circuit 74. In this way, an ultrasonic tomographic image is drawn on the monitor device 3.

As described above, according to this embodiment, the ultrasonic reflecting mirror 51
Since the rotation angle of the sensor can be detected digitally, detection accuracy is greatly improved, and subsequent signal processing can be performed easily. Furthermore, since there is no need to use a rotation angle detection plate as in the conventional case, the device itself becomes smaller. Furthermore, temperature characteristics are also improved.

FIG. 13 shows a second embodiment of the present invention.

In this embodiment, a bit string 80 is provided on the cylindrical side surface of an ultrasonic reflecting mirror 820 via a ground electrode 81.

According to the second embodiment, the length of the distal end of the insertion section in the intracorporeal ultrasound diagnostic apparatus can be shortened.

Further, FIG. 14 shows a third embodiment of the present invention.

In this embodiment, the ultrasonic probe 90 is directly rotated without using an ultrasonic reflector to perform radial scanning, and the bit row 91 formed at the edge of the cylindrical bottom surface of the ultrasonic probe 90 is used to perform radial scanning. This rotation angle is detected. At that time, this ultrasonic probe 90
Electrical signals are supplied to the connector 92 via a connector 92.

According to this embodiment, compared to the first and second embodiments, the shape of the distal end of the insertion portion of the intracorporeal ultrasonic diagnostic apparatus is further reduced in size.

In addition, in the first to third embodiments, explanations are given using radial scanning with unidirectional rotation as an example, but the method is not limited to this scanning method, and is not limited to ultrasonic scanning using reciprocating rotational motion such as the Galber-Skiina. Needless to say, the present invention can also be applied to scanning methods.

As described above, according to the present invention, the rotation angle of the ultrasonic wave transmitting/receiving unit such as an ultrasonic probe or an ultrasonic reflector can be detected as a digital quantity, so the detection accuracy can be greatly improved, thereby making it possible to improve the image quality. It is possible to provide an intrabody cavity ultrasonic scanning device that can provide clear images while simplifying and downsizing the device itself.

[Brief explanation of the drawing]

Figure 1 is an external view of a conventional intrabody cavity ultrasound diagnostic device, Figure 2 is an enlarged sectional view of the tip of the insertion section in Figure 1, and Figure 3 is a perspective view of only the rotation angle detection mechanism in Figure 2. FIG. 4 is a block diagram showing a control processing circuit etc. in a conventional ultrasound scanning device, and FIGS. 5 to 12 are diagrams showing a first embodiment of the present invention. Enlarged sectional view of the tip of the insertion section in the internal ultrasound diagnostic device, FIGS. 6 and 7
Figures (,) (b) are a perspective view, front view, and side view of the ultrasonic reflector in Figure 5; Figure 8 is an enlarged perspective view of the slider in Figure 5; Figure 9 is an enlarged perspective view of the slider in Figure 5; Fig. 10 is a block diagram showing the control processing circuit, etc. Fig. 11 is a diagram showing the frequency characteristics of the resonant circuit according to the rotation of the ultrasonic reflecting mirror. FIG. 12 is a waveform diagram showing the operation of the block diagram in FIG. 1O, and FIGS. 13 and 14 are diagrams showing second and third embodiments of the present invention, respectively. J... Endoscope, 2... Control processing circuit, 3... Monitor device, L... Insertion section, 7... Storage section, 8... Illumination window, 9... Observation window, 10... light guide,
11...Imeno guide, 12,51.82...Ultrasonic reflector, 14...Rotation angle detection plate, 16.90.
...Ultrasonic probe, 18...Balloon rubber, 2o...
・Ultrasonic transmission medium, 21, 22°°° optical fiber, 23... Light emitting element, 24... Light receiving purple element, 50
, 80°91... Bit string, 52.83... Slider, 53°81... Ground electrode, 92... Connector. Applicant's representative Patent attorney Takehiko Suzue Figure 1 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Procedural amendments November 1, 1939 Commissioner of the Japan Patent Office Kazuo Wakasugi 1. Indication of the case Patent Application No. 57-176644 No. 2 Title of the invention Intrabody cavity ultrasonic scanning device 3 Relationship to the case of the person making the amendment Patent applicant (037) Olympus Optical Industry Co., Ltd. 4 Agent address 1 Toranomon, Minato-ku, Tokyo Chome 26-5 No. 17 Mori Pill 〒105 Phone 03 (502) 3181 (
Main representative) 6. Subject of correction

Claims (5)

[Claims] (1) A rotatable or rotatable ultrasonic wave transmitting/receiving unit, a plate-shaped first electrode provided along the rotational direction of the ultrasonic wave transmitting/receiving unit, and a plate-shaped first electrode arranged at a predetermined interval on the first electrode. A bit string consisting of a plurality of dielectric bits arranged in the circumferential direction, a second electrode provided so as to be in sequential sliding contact with each bit of the bit string, and a second electrode formed by rotation or rotation of the ultrasonic wave transmitting/receiving section. - and a means for detecting a change in capacitance occurring between the second electrodes and generating a digital pulse according to the rotation or rotation angle of the ultrasonic wave transmitting/receiving section. Ultrasonic scanning device. (2) The intrabody cavity ultrasonic scanning device according to claim (1), wherein the ultrasonic wave transmitting/receiving section is a rotatable or rotatable ultrasonic reflecting mirror. (3) Claim (1) characterized in that the ultrasonic wave transmitter/receiver is a rotatable or rotatable ultrasonic probe.
The intrabody cavity ultrasonic scanning device described in Section 1. (4) The intrabody cavity ultrasonic scanning device according to claim (1), wherein the bit string is provided on the cylindrical bottom surface or the cylindrical side wall of the ultrasonic wave transmitting/receiving section. (5) Claim No. (1) characterized in that the specific bit of the bit string has a different shape from other bits.
The intrabody cavity ultrasonic scanning device described in Section 1.