JPS59142460A - Ultrasonic video device - Google Patents

Abstract

PURPOSE:To improve operability of a device, and to make it small-sized by receiving an ultrasonic wave, irradiating light to an ultrasonic light transducing member for forming a standing wave, detecting a variation of quantity of light of its transmitting light or reflected light, and leading it to a light emitting part. CONSTITUTION:An ultrasonic wave from a transducer 1 transmits through an object 2, is modulated, and forms an image on an ultrasonic incident part 6 by an ultrasonic lens 3. The ultrasonic incident part is placed with regularity on a two-dimensional plane, therefore, an ultrasonic image is propagated through the inside of an ultrasonic path 5 as a spot image of the number of this ultrasonic incident part, and becomes a stationary state by being resonated in an ultrasonic light transducing member 7. On the other hand, a light of narrow wavelength width, which passes through an interference filter 9 from a light source 8, and is irradiated to the ultrasonic light transducing member 7 by a condenser lens 10 is diffracted by an ultrasonic wave of a stationary state and led to an optical fiber 11. In this way, the operability is improved and also the device becomes small-sized.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an ultrasonic imaging device that replaces and displays an image of an object to be examined using ultrasonic waves with an optical image that can be visually determined.

Conventional devices of this type arrange ultrasonic probes in a two-dimensional array as detectors on the ultrasonic image plane, scan each element sequentially, and convert it into an electrical signal proportional to the ultrasonic sound field. ,
Visualization has been achieved by lighting bright spots at locations corresponding to the positions of the elements on a CRT monitor, but as the number of elements increases, the scanning time increases, resulting in poor responsiveness. Further, there are problems in that there is interference between elements and the device becomes complicated and large.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the above-mentioned conventional examples and to provide a compact and portable ultrasound imaging device with a simple structure.

To achieve this objective, the present invention includes an ultrasonic light conversion member that receives ultrasonic waves and forms standing waves, irradiates this with light, and detects changes in the amount of transmitted light or reflected light. Furthermore, it is characterized in that direct light conversion is performed for each pixel using a plurality of ultrasonic light conversion members.

The present invention will be explained in detail below.

FIG. 1 shows an embodiment of the present invention, in which 1 is a transducer for emitting ultrasonic energy, 2 is an object to be imaged by ultrasound, 5 is an ultrasound lens, and 4 is an ultrasound path mirror. A support member 7 located at one end of the ultrasonic wave path 5 is used to support the ultrasonic wave incidence section 6 at a certain height.
It is an ultrasonic light conversion member that is ultrasonically coupled with the ultrasonic wave resonator and becomes an ultrasonic resonator and is transparent to light. Further, 8 is a light source, 9 is an interference filter for wavelength selection, 10 is a condenser lens, and 11 is a former shear bar, one end of which is optically coupled to the ultrasonic light conversion member 7, and the other end of which is connected to the ultrasonic light conversion member 7. It is held by a support member 16 in a position corresponding to the sound wave incidence section 6 . The light emitting portion 12 of the optical fiber 11 is held with regularity by the support member 16 in correspondence with the ultrasonic wave incident portion 4 . Note that 14 indicates the observer's eyes.

FIG. 2 shows a plan view of the apparatus shown in FIG.

In the figure, 10/ is a lens for irradiating the optical fiber 11 with the light beam diffracted by the ultrasonic light conversion member 7, which is used as necessary.

Here, the ultrasonic light conversion member 7 has the following structure and function.

The ultrasonic light conversion member 7 is, for example, a cell whose periphery is surrounded by glass and has a structure in which medium-pressure liquid is sealed, and whose frame walls are set at intervals of an integral multiple of a half wavelength in the medium in the ultrasonic propagation direction to form a resonant tube. It has a shaped member.

This cellular member is disposed at a part or end of the ultrasonic waveguide 5, and may be a liquid element or a solid element such as a transparent crystal set to the resonance length of the ultrasonic wave.

Here, the ultrasonic waves are continuously emitted, and the ultrasonic waves that propagated through the ultrasonic waveguide are emitted into the cellular member, where they interfere and form a stationary wave front, creating a so-called ultrasonic grating. Formed stably over time.

Here, the ultrasonic waves from the transducer 1 are transmitted through the object 2 and modulated, and an image is formed on the ultrasonic incidence section 6 by the ultrasonic lens 6. Since the ultrasound incidence parts are arranged with regularity in a two-dimensional plane, the ultrasound image propagates inside the ultrasound path 5 as a point image corresponding to the number of ultrasound incidence parts, and ultrasonic light conversion occurs. A steady state is achieved by resonating within the member 7. On the other hand, the light beam from the light source 8 passes through the interference filter 9 and is irradiated onto the ultrasonic light conversion member 7 by the condenser lens 10, and is diffracted by steady-state ultrasonic waves and guided to the source fiber 11.

That is, the light incident on the cellular member is diffracted, and the absolute amount of the light beam reaching the fiber surface facing the incident light is reduced, and the amount of light from the fiber exit portion is reduced. When converting an ultrasound image into a light image, this creates an image (negative image) that is inversely proportional to the intensity of the ultrasound.

In this example, the fiber is set at a position facing the incident light, but if the fiber is set in the diffraction direction, the amount of light to the fiber increases when the ultrasonic wave is incident,
The amount of light at the fiber exit portion increases, and an image (positive image) proportional to the intensity of the ultrasonic wave is formed by this K. Note that in the present invention, the detection of transmitted light or reflected light is not limited to optical fibers, but also uses a focusing optical fiber element (trade name SELFOC).
etc. may also be used.

Furthermore, the present invention is not necessarily limited to the phenomenon of light diffraction due to the ultrasonic wavefront, but can also utilize the reduction in light due to scattering when ultrasonic waves are continuously propagated.

Therefore, the irradiated light does not have to be a complete spectrum line, and may have a wavelength width of about 200 to 30°.

Note that the cellular member is not necessarily limited to the terminal end of the ultrasonic waveguide, but may be provided in the middle, and the ultrasonic waveguide may also serve as that function.) Also, a laser is used as the light source. It is also possible to obtain a clearer image by spreading the light flux using the optical system pressure and irradiating it onto a plurality of ultrasonic light conversion members.

Furthermore, in the present invention, binarized (digital) images based on the presence or absence of ultrasonic input are also possible.

FIG. 6 shows a different embodiment of the ultrasonic light conversion member, which uses vibration mode conversion.

- An image is obtained by dividing the pixels in the screen into nine mosaic-like parts and replacing it with light to indicate whether or not the ultrasound has propagated.The ultrasonic waveguide must be as thin as possible without interfering with the propagation of the ultrasound. is good. In this case) it is suitable to directly set a rod-shaped member or a plate-shaped member as the ultrasonic light conversion member to convert the vibration mode from longitudinal waves to transverse waves. In other words, in FIG. 3, a thin plate-shaped resonance system member 15 is disposed at a part or the end of the ultrasonic waveguide, and the vibration mode is converted here, and the vibration that occurs when the ultrasonic wave is propagated by irradiating light thereon is converted into a vibration mode. Diffuse reflection of light due to mechanical vibration of the resonance system member or change in light amount due to change in reflection angle is detected. This resonance system member 15 couples the just-propagated ultrasonic waves at an angle that allows them to be easily converted into plate waves.

Further, the fiber is set so that the light is focused on the surface of the resonant member and the specularly reflected light is detected.

The ultrasonic wave propagating through the ultrasonic waveguide propagates as a plate wave in the resonant member, causing the resonant member to vibrate in the direction of the plate thickness, and the incident light beam is swayed at an arbitrary angle and reaches the fiber trap unit. The amount of light per hour changes, and the brightness at the fiber exit port changes.

In this embodiment as well, by setting the fiber at a position shifted from the specular reflection position, it is possible to obtain an optical signal commensurate with the ultrasonic human power.

Furthermore, when detecting changes in the amount of transmitted light, a position pressure fiber corresponding to the transmitted light is set up, and a diffraction grating is provided on the surface of the resonant member that is transparent to light, or a diffraction surface is used to detect the change in the amount of transmitted light. Apply pressure to obtain a change in light amount. .

FIG. 4 shows an embodiment of mode conversion for efficient propagation when the ultrasonic waveguide is miniaturized.

If the ultrasonic velocity of the longitudinal wave 16 is vl, the incident angle is i1 mode, the ultrasonic velocity of the transverse wave 17 converted to mode is υ2, and the refraction angle is θ, 1v1 i (sin □ 2 , -1 ν2 θ=sxn (X 5inL) 1 may be satisfied.

In the same way, it is also possible to convert system vibrations in the form of ultra-thin rods.

Alternatively, an extremely thin plate with high reflectance may be bonded in a predetermined direction, and the reflected light may be detected.

Next, FIG. 5 is a diagram showing the arrangement of pixels in the ultrasound incidence part and the light emission part, where 18 is the arrangement of the ultrasound incidence part, 19.2
0 indicates the arrangement of the light emitting section.

For ultrasound imaging, the ultrasound lens 6 is used as shown in Figure 1.
When an ultrasonic image is formed using the light beam and the light emitting section 12 is directly viewed by changing the light beam, an erect image can be obtained by adopting the arrangement of 18 and 20 in FIG.

Note that the object 2 is placed in the ultrasonic incidence section 6 without using the ultrasonic lens 6.
When the trap comes in close contact with the trap, an erect image can be obtained by placing the trap in the position 18 and 9 in FIG. Here, carrying out the method without using the ultrasonic lens 6 is an effective method when the object is relatively thin, since there is no influence of scattering etc. during the propagation of the ultrasonic waves.

As explained above, in an ultrasonic imaging device for the purpose of ultrasonic light conversion, there is no need to electrically scan dotted pixels arranged in an IJ rack in a two-dimensional plane, simplifying the system. In addition to achieving compactness, the image time is reduced by 30 minutes because point pixels are transmitted to the observation system in the same time.
It is possible to improve it by about 10 times to 10 times.

Therefore, the operability of the device is greatly improved, and it can be easily used for underwater observation, which has been considered difficult in the past, as well as non-destructive testing and medical applications.

[Brief explanation of the drawing]

Fig. 1 is a diagram of an embodiment of the device according to the present invention, Fig. 2 is a plan view of the device shown in Fig. 1, Fig. 6 is a diagram of a different embodiment using vibration mode conversion, and Fig. 4 is a diagram of vibration modes. An explanatory diagram of conversion. Figure 5 is a diagram of a pixel arrangement. In the diagram, 1 is a transducer 12 is an object, 6 is an ultrasound lens, 5 is an ultrasound path, 6 is an ultrasound incidence part, and 7 is an ultrasound light r conversion member, 8 a light source, 9 a wavelength selection interference filter, 10
11 is an optical fiber, 12 is a light emitting part, 15 is a resonance system member, 16 is a longitudinal wave, and 17 is a transverse wave. Applicant Canon Co., Ltd.

Claims (1)

[Claims] 1. In an ultrasound imaging device that receives an ultrasound signal from a subject and converts it into light, the means includes a means for receiving the ultrasound signal and forming a standing wave; means for irradiating, and detecting transmitted light or reflected light from the standing wave forming means,
An ultrasonic imaging device characterized by having a light guide means for guiding the light to a light emitting section. 2. The ultrasound imaging apparatus according to claim 1, wherein the standing wave forming means forms a standing wave as a longitudinal wave. 6. The ultrasound imaging apparatus according to claim 1, wherein a plurality of standing waves are provided, wherein the standing wave forming means forms a standing wave as a transverse wave whose vibration mode has been converted. 5. The ultrasonic imaging apparatus according to claim 4, wherein the light receiving direction of the light guiding means is opposed to the light projecting direction of the irradiating means, and the light is converted into a negative image. 6. The ultrasonic imaging apparatus according to claim 4, wherein the light receiving direction of the light guide means is arranged obliquely to the light projection direction of the irradiation means, and the light is converted into a positive image. 7. Claim 4, wherein the incident portion and the exit portion of each of the light guiding means are associated to form a regular pixel array.
The ultrasonic imaging device described in Section 1.