A glimpse of ultrasonics in China An account People’s
from
Professor
Republic
of China
Greguss
on his recent
The People’s Republic of China is as much a land of the world’s oldest continuous civilization as a country urgently in need of science and technology to become a modern nation. This, however, does not mean that there is no real science in the Republic, only that the science stratum is rather restricted, and that even its influence was severely disrupted in the near past. We are at the present time witnessing great changes in China, and therefore it was indeed a great experience for us, for my wife and myself, to see as guests of the National Academy of Sciences (Academia Sinica) those efforts which are part of an aim that by the end of this century China be among the advanced scientific and industrial nations.
visit to various
laboratories
in the
Fig. 1
The acoustical holographic system in operation
Fig. 2
Acoustical hologram of the upper arm
Coming from the 6th International Biophysics Congress held in Kyoto, Japan, in September 1978, we flew to Shanghai. Here we were greated by the representatives of the Academia Sinica, Lu Guan-hu, Fu Zi-Liang, a staff member of the Library of the Academia Sinica (he was our interpreter during our stay in China, a wonderful man to whom we are really indebted), Mrs. C.F. Wang, head of a department of the Shanghai Institute of Laser Technology*, and Prof. S.T. Shae, head of the Section of Holographic Research and Time-Lapse Cinematography, Shanghai Institute of Cell Biology, of the Academia Sinica. Prof. Shae’s laboratory is certainly of interest to the readers of Ultrasonics, since a lot of ultrasonics-related research is being made in this laboratory, despite its name. The most spectacular results achieved by Prof. Shae and his staff are with the development of a versatile ultrasonic holographic set-up, primarily not for medical diagnostics but rather for biological laboratory research. To record the intensity distribution of the acoustic hologram he uses the liquid surface levitation method first described by Sokolov in the late 20’s, and then rediscovered by Brenden for acoustic holography in the late 60’s. Fig. 1 shows one of the staff members adjusting the monitor of their acoustical holographic system, while Fig. 2 is an acoustic holographic image of the upper arm as photographed directly from the tv monitor. Prof. Dr. Pal Greguss, Director, Applied Biophysics Laboratory, Technical University Budapest, Kruspei u. 24, H-Ill1 Budapest, Hungary
134
Since I have had the opportunity to see several acoustic holographic equipments based on this principle in various laboratories around the world, I can state that the quality of the reconstructed acoustic images was not inferior but rather superior to those made in Western laboratories. Most of the constitutents of the acoustic holographic set-up were produced in China, and several parts of it have been developed in this laboratory or under the guidance of these researchers. The laboratory had its facilities for developing ultrasonic transducers and both solid and liquid-filled acoustic lenses up to 250-300 mm in diameter. + For a report on a visit to this Institute, see Optics and Laser Technology, June 1979
ULTRASONICS.
MAY 1979
Although mainly engaged in the different problems of acoustical holography, the laboratory is in close collaboration with institutes developing conventional ultrasonic medical diagnostic methods and equipment such as A, B and M-mode scanners, and even multielement transducers for real-time ultrasonic imaging. At present, a 60 element electronically scanned transducer is under development. Unfortunately, we had such a full programme that there was no time to visit the laboratories where medical ultrasonic equipment is being developed and/or used. Nevertheless, we got an insight into their efforts to use ultrasound in the medical field from Shu Chi Chang, MD, one of the leading Chinese experts in ultrasonic medical diagnostics and co-author of the recently (in Shanghai) published book “Ultrasonic Diagnostics”, who gave us a copy of this book. Although my knowledge of Chinese is rather poor, I could judge that this book of 300 pages is not only up-to-date, but it is excellently written, and its method of introduction gives evidence of great pedagogical feeling of the author’s collective. Since China is closer to Japan than to the United States, it was not surprising that the design of the Chinese ultrasonic diagnostic equipment shows perhaps more Japanese than American influence.
At the end of our visit to this laboratory, Prof. Shae showed us an excellent film on their acoustic holographic equipment, which has just been finished and which demonstrated that Prof. Shae is also skilful in research filming. The next laboratory we visited was the Department of Acoustics of the Institute of Physics of the Academia Sinica in Peking, headed by Prof. Ying Tsung-Fu, an old friend of ours. The research activity of this department is manifold, but two distinct directions could be perceived. One was acoustics in the sense of speech research, noise research and, recently, infrasound research. The other, perhaps more heavily represented research direction was a broad band of ultrasonics, however, more or less restricted to ultrasonic metrology. A rather large group is engaged in developing ultrasonic transducers for frequencies ranging from kHz up to GHz, and they are very interested in sandwich type transducers. As a natural result of the activity of this group, another group is concerned with manufacturing techniques of piezoelectric materials. They are growing not only lithium-niobate and zinc-niobate crystals but, for instance, bismuth and germanium silicate crystals too. They have developed a new floating-crystal growing and drawing technique which enables them to make in a single step tubes several centimetres long from these piezoelectric materials. Further groups are studying the ultrasonic wave propagation and scattering on surface waves and in various solids, and their aim is to perform these studies at frequencies up to 1Ol2 Hz! Besides doing basic research, the staff of this department tries to get in touch with industry to help them to solve some of their problems by ultrasonic means.
Fig. 3
Sonocardiogram
of a left atrium myxoma
We have been told that Chinese-made ultrasonic diagnostic equipment is now used in several hospitals and clinics. Fig. 3 shows a sonocardiogram of a left atrium myxoma recorded with Chinese-made equipment in clinical practice.
ULTRASONICS.
MAY 1979
We visited not only ultrasonics-related laboratories, but we had also the opportunity to discuss different scientific issues at seminars and informal talks in Shanghai as well as in Peking. The conclusion that we have drawn is that Chinese scientists are eager to march toward the modernization of science and technology, but to achieve their goal they need more than a few top scientists, they need, as vice-premier Fang Yi pointed out, to “pull their efforts to foster among the cadres, the masses, and the young people, the habit of loving, studying and applying science.”
135
from
Professor
Republic
of China
Greguss
on his recent
The People’s Republic of China is as much a land of the world’s oldest continuous civilization as a country urgently in need of science and technology to become a modern nation. This, however, does not mean that there is no real science in the Republic, only that the science stratum is rather restricted, and that even its influence was severely disrupted in the near past. We are at the present time witnessing great changes in China, and therefore it was indeed a great experience for us, for my wife and myself, to see as guests of the National Academy of Sciences (Academia Sinica) those efforts which are part of an aim that by the end of this century China be among the advanced scientific and industrial nations.
visit to various
laboratories
in the
Fig. 1
The acoustical holographic system in operation
Fig. 2
Acoustical hologram of the upper arm
Coming from the 6th International Biophysics Congress held in Kyoto, Japan, in September 1978, we flew to Shanghai. Here we were greated by the representatives of the Academia Sinica, Lu Guan-hu, Fu Zi-Liang, a staff member of the Library of the Academia Sinica (he was our interpreter during our stay in China, a wonderful man to whom we are really indebted), Mrs. C.F. Wang, head of a department of the Shanghai Institute of Laser Technology*, and Prof. S.T. Shae, head of the Section of Holographic Research and Time-Lapse Cinematography, Shanghai Institute of Cell Biology, of the Academia Sinica. Prof. Shae’s laboratory is certainly of interest to the readers of Ultrasonics, since a lot of ultrasonics-related research is being made in this laboratory, despite its name. The most spectacular results achieved by Prof. Shae and his staff are with the development of a versatile ultrasonic holographic set-up, primarily not for medical diagnostics but rather for biological laboratory research. To record the intensity distribution of the acoustic hologram he uses the liquid surface levitation method first described by Sokolov in the late 20’s, and then rediscovered by Brenden for acoustic holography in the late 60’s. Fig. 1 shows one of the staff members adjusting the monitor of their acoustical holographic system, while Fig. 2 is an acoustic holographic image of the upper arm as photographed directly from the tv monitor. Prof. Dr. Pal Greguss, Director, Applied Biophysics Laboratory, Technical University Budapest, Kruspei u. 24, H-Ill1 Budapest, Hungary
134
Since I have had the opportunity to see several acoustic holographic equipments based on this principle in various laboratories around the world, I can state that the quality of the reconstructed acoustic images was not inferior but rather superior to those made in Western laboratories. Most of the constitutents of the acoustic holographic set-up were produced in China, and several parts of it have been developed in this laboratory or under the guidance of these researchers. The laboratory had its facilities for developing ultrasonic transducers and both solid and liquid-filled acoustic lenses up to 250-300 mm in diameter. + For a report on a visit to this Institute, see Optics and Laser Technology, June 1979
ULTRASONICS.
MAY 1979
Although mainly engaged in the different problems of acoustical holography, the laboratory is in close collaboration with institutes developing conventional ultrasonic medical diagnostic methods and equipment such as A, B and M-mode scanners, and even multielement transducers for real-time ultrasonic imaging. At present, a 60 element electronically scanned transducer is under development. Unfortunately, we had such a full programme that there was no time to visit the laboratories where medical ultrasonic equipment is being developed and/or used. Nevertheless, we got an insight into their efforts to use ultrasound in the medical field from Shu Chi Chang, MD, one of the leading Chinese experts in ultrasonic medical diagnostics and co-author of the recently (in Shanghai) published book “Ultrasonic Diagnostics”, who gave us a copy of this book. Although my knowledge of Chinese is rather poor, I could judge that this book of 300 pages is not only up-to-date, but it is excellently written, and its method of introduction gives evidence of great pedagogical feeling of the author’s collective. Since China is closer to Japan than to the United States, it was not surprising that the design of the Chinese ultrasonic diagnostic equipment shows perhaps more Japanese than American influence.
At the end of our visit to this laboratory, Prof. Shae showed us an excellent film on their acoustic holographic equipment, which has just been finished and which demonstrated that Prof. Shae is also skilful in research filming. The next laboratory we visited was the Department of Acoustics of the Institute of Physics of the Academia Sinica in Peking, headed by Prof. Ying Tsung-Fu, an old friend of ours. The research activity of this department is manifold, but two distinct directions could be perceived. One was acoustics in the sense of speech research, noise research and, recently, infrasound research. The other, perhaps more heavily represented research direction was a broad band of ultrasonics, however, more or less restricted to ultrasonic metrology. A rather large group is engaged in developing ultrasonic transducers for frequencies ranging from kHz up to GHz, and they are very interested in sandwich type transducers. As a natural result of the activity of this group, another group is concerned with manufacturing techniques of piezoelectric materials. They are growing not only lithium-niobate and zinc-niobate crystals but, for instance, bismuth and germanium silicate crystals too. They have developed a new floating-crystal growing and drawing technique which enables them to make in a single step tubes several centimetres long from these piezoelectric materials. Further groups are studying the ultrasonic wave propagation and scattering on surface waves and in various solids, and their aim is to perform these studies at frequencies up to 1Ol2 Hz! Besides doing basic research, the staff of this department tries to get in touch with industry to help them to solve some of their problems by ultrasonic means.
Fig. 3
Sonocardiogram
of a left atrium myxoma
We have been told that Chinese-made ultrasonic diagnostic equipment is now used in several hospitals and clinics. Fig. 3 shows a sonocardiogram of a left atrium myxoma recorded with Chinese-made equipment in clinical practice.
ULTRASONICS.
MAY 1979
We visited not only ultrasonics-related laboratories, but we had also the opportunity to discuss different scientific issues at seminars and informal talks in Shanghai as well as in Peking. The conclusion that we have drawn is that Chinese scientists are eager to march toward the modernization of science and technology, but to achieve their goal they need more than a few top scientists, they need, as vice-premier Fang Yi pointed out, to “pull their efforts to foster among the cadres, the masses, and the young people, the habit of loving, studying and applying science.”
135
