This paper gives a brief survey on some major developments on highspeed photography and photonics in China. History and organisation thereon are shortly reviewed. The technological aspects are illustrated by various kinds of cameras and devices developed and manufactured, such as the category of opto-mechanical cameras, the image converter and streak cameras, highspeed holography and interferometry, ultra short optical pulse etc. Some technical data are given to indicate their technical levels achieved. Examples of applications are also given to show their utilisation in various field of national construction as well as in scientific research.

In the past decade, high speed photography has been rapidly incorporating electrooptics. More recently, optoelectronics and digital recording of images for specialized laboratory cameras and commerically available systems have helped broaden the versatility and applications of high speed photography and photonics. This paper will highlight some of these technologies and specialized systems.

A brief historical review of temporal-analyzing image converter tubes(ICT) development in our country is presented. Some recent results in designing and manufacturing of the tubes capable to operate in visible, near infrared, ultraviolet and soft X-ray spectral regions are given. There is a great variety of the available image converter tubes which provide pico and femtosecond temporal resolution in circular, single streak and synchroscan mode of operation, as well as picosecond resolution in single and multiframe photography. High technical parameters of the created tubes ensure their successful application for high speed events recording in laser and plasma physics research, solid state and semiconductor physics, nonlinear and fibre optics, microelectronics and optical computing, laser ranging, mind/brains imaging, and so on. Further directions in designing of completely new type of temporal-analysing image converter tubes, will be outlined, while the special attention will be drawn to the tubes with the electron beam sensitive CCD detectors.

State-of-the-art picosecond and femtosecond pulse lasers for which optical nonlinearity in extracavity or intracavity/coupled-cavity configurations has been exploited are reviewed. Particular implications with regard to electron-optical streak camera diagnostics have been indicated where appropriate.

The "Centre d'Etudes de LIMEIL-VALENTON", since 1962, has maintained a continuous effort in the developpement of all techniques involved in Laser-Plasma Experiments. This includes not only laser technology but also diagnostics studies and targets design and fabrication. Among the different kind of diagnostics currently used are High Speed Streak Cameras, fast Oscilloscopes and detectors sensitive in the I.R., visible, the U.V. region and the X-rays. In this presentation we will describe the three high power lasers which are still in operation (P 102, OCTAL and PHEBUS) and the main diagnostics used to characterize the plasma.

The application of laser power densities above the plasma ignition threshold to any dielectric, semiconducting or metallic target material is capable of providing a most efficient energy transfer by an enhanced coupling mechanism. The present paper is concerned with experimental investigations of pulsed laser target interaction phenomena in a medium power density range below air breakdown threshold. When infrared lasers are considered, these values are in the range of some hundreds of MW/cm2 or even below, for UV-lasers these values may be higher by one or two orders of magnitude. This range is of particular interest, as plasma induced thermo-mechanical processes are governing and improving the energy transfer. Many of the processes involved have been investigated for single pulse operation. The most interesting features are occurring, however, if trains of pulses are applied, thereby building up high average power densities so that target effects are integrated. temporally. These effects are then increasing rapidly giving rise to fast heating, melting, vaporization and subsequent ablation, including thermally induced chemical reactions. The paper gives an overview on current research in the above mentioned field and describes recent measurements performed at the ISL Saint-Louis. Main emphasis is layed on discussing the various types of fast electrical and optical diagnostic principles and techniques used for the optimization of the energy transfer rates at this particular high average power density range.

We have made a nanoseconds framing camera with the second generation image intensifiers and have photographed the images of 5 ns framing time with GZ2-2030T image intensifiers. The resolution is 10 1p/mm. The photographable photo-dynamic region is 100 times. The shutting action is achieved by appling a -800 V gating pulse to the quiscently zero-biased MCP input--output interface. Gating speeds and the quiescently bias influnce on them, the maximum photographable photo-dynamic region, the spatial response of the phosphor screen for uniform photo-cathode illumination have characterized. The characterization system,gating and bias-ing circuit will be presented.

In this paper, a new picosecond synchroscan streak camera system, including our own synchroscan streak image tube, RF streak circuits and CPM laser system, has been reported. The temporal resolution of the streak image tube itself was 300fs and spatial resolution was 50 1p/mm. The dynamic sensitivity of deflection was 10cm/kV and factor of merit was greater than 100, which decreased the requirement of the RF deflection power to the streak circuits. Our RF streak circuits consisted of PIN diode, electric second harmonic selector, pre-amplifier, power amplifier and impedance matching unit, which gave maximum RF power of lOw and operation frequancy of 200MHz. The CPM dye laser system developed in our laboratory was pumped by an Ar? laser system and presented the shortest pulse duration of +5fs and repetation rate of 100MHz with acceptable stability. The preliminary experiments showed that the temporal resolution of 2ps of the whole camera system was obtained which was limi-ted by the stabilities of above laser system and RF streak circuits.

A series of Anglo-Soviet picosecond streak/synchroscan cameras was designed for application in various branches of science and technology. We are analyzing some of the most important steps in arranging of this joint camera production as well as briefly discussing further directions of our activity. Dynamic tests of mutually developed streak/synchroscan cameras are described.

The paper has pointed out that the electron transit time dispersion is much worse in the case of the quad tail energy distribution (QTED) typical of x-ray photocathodes in the photo-cathode to mesh region of picosecond image tubes. The temporal abberations of a whole tube have been calculated on condition of a spherical photocathode and concentric a spherical mesh. The paper has put forward a principle of the temporal compensator for the purpose of obtaining the limiting time resolution (about 10-14sec. for the visible light) of image tubes and abolishing the grid mesh which effects seriously the processing of high sensitivity photocathode. It is a electron pulse compressor in essence and has the same action as the mesh.

Described are the comparative testing of two type of electron-optical recording instruments, namely, TDS simplified streak device designed and manufactured at the Centre of Scientific Instruments, GDR Academy of Sciences, and anglo-soviet Imacon 500 picosecond streak camera fitted with PV-001 tube. The Imacon 500 streak camera was matched with a SIT vidicon readout system. Temporal resolution, dynamic range and input sensitivity were estimated for the same recording conditions. It was shown that for 6 ps laser probe pulses the TDS dynamic sensitivity at 530 nm input radiation is only four times less comparative to the commercial Imacon 500 system, while both systems have almost the same dynamic range.

In our specially designed femtosecond streak image tube, the electron beam was focused by a cylindrical electron optical lens. In order to achieve temporal resolution of less than 50fs and large dynamic range, the electric field near the photocathode was 6-8kV/mm with a slit acceleration electrode. The temporal dispersion in our lens has been eliminated completely by optimization of the electron focusing lens. To compensate the temporal dispersion arising from photocathode to accelerating electrode, a compensation element and a half open aperture have been introduced, so that the total temporal dispersion of less than 50fs has been achieved. To overcome the influence of a strong fringe field of the deflector in dynamic mode on the total temporal dispersion and spatial resolution, a travelling wave deflector will be used. In addition, to minimize the space charge effects, the electron transit time in this specially designed electron optical lens was shortened to 840ps and the so called crossover in slit direction disappeared. The discrete space charge effects have been modeled by Monte Carlo method including photoelectron emission process and induced charge on the electrode. The calculations have shown that this tube can handle the current density of up to 20A/cm2 without deterioration of the temporal resolution.

A nanosecond single frame camera by gating the 25mm proximity focused microchannel plate (MCP) intensifier has been developed at our institute. On the basis of previous researches on proximity focused microchannel plate intersifier tube (MCPT) for gating application, it has been payed more attention in this programme to developing a commonly used camera with gating time < 10 ns. The structure of the camera, the MCPT for fast gating application, the gating pulser and the way to connect the pulser to the MCPT are presented. The characteristics of the camera are discussed. When the tube is gated by a 2 ns FWHM driving electrical pulse, measured resolution is 4.7 1p/mm.

This paper has mainly discussed the design aspects of an optical system for a femtosecond streak tube camera. The optical system produces the negative temporal distortion of 3.5 ps at the maxmum visual field, so the positive temporal distortion of a fs streak tube can be remedied, it results in that the temporal distortion of the whole system has been less than 50 fs. In addition, it can be used for three wave ranges depending on the light source.

The paper reports on the design of an ICI camera operating in the mode of linear or three-frame image scan. The camera incorporates two tubes: time-analyzing ICI PIM-107 1 with cathode S-11, and brightness amplifier PMU-2V (gain about 104) for the image shaped by the first tube. The camera is designed on the basis of streak camera AGAT-SF3 2 with almost the same power sources, but substantially modified pulse electronics. Schematically, the design of tube PIM-107 is depicted in the figure. The tube consists of cermet housing 1, photocathode 2 made in a separate vacuum volume and introduced into the housing by means of a manipulator. In a direct vicinity of the photocathode, accelerating electrode is located made of a fine-structure grid. An electrostatic lens formed by focusing electrode 4 and anode diaphragm 5 produces a beam of electrons with a "remote crossover". The authors have suggested this term for an electron beam whose crossover is 40 to 60 mm away from the anode diaphragm plane which guarantees high sensitivity of scan plates 6 with respect to multiaperture framing diaphragm 7. Beyond every diaphragm aperture, a pair of deflecting plates 8 is found shielded from compensation plates 10 by diaphragm 9. The electronic image produced by the photocathode is focused on luminescent screen 11. The tube is controlled with the help of two saw-tooth voltages applied in antiphase across plates 6 and 10. Plates 6 serve for sweeping the electron beam over the surface of diaphragm 7. The beam is either allowed toward the screen, or delayed by the diaphragm walls. In such a manner, three frames are obtained, the number corresponding to that of the diaphragm apertures. Plates 10 serve for stopping the compensation of the image streak sweep on the screen. To avoid overlapping of frames, plates 8 receive static potentials responsible for shifting frames on the screen. Changing the potentials applied to plates 8, one can control the spacing between frames and partially or fully overlap the frames. This sort of control is independent of the frequency of frame running and of their duration, and can only determine frame positioning on the screen. Since diaphragm 7 is located in the area of crossover and electron trajectories cross in the crossover, the frame is not decomposed into separate elements during its formation. The image is transferred onto the screen practically within the entire time of frame duration increasing the aperture ratio of the tube as compared to that in Ref. 3.

A numerical assessment of the role of phase noise in the synchroscan deflection signal and its effect on achievable streak camera temporal resolution is detailed and tested experimentally. The circuitry employed in the synchroscan streak operation of the Photochron IV camera system is described. The experimental performance of two synchronisation systems, (i) a passive configuration whereby the deflection signal is derived directly from a mode-locked pulse source and, (ii) an active system incorporating a tunnel-diode oscillator phase-locked to the laser, have been experimentally compared. By taking phase noise into account the circuitry has been appropriately optimised and this has permitted the demonstration, in synchroscan mode, of a limiting temporal resolution of 930 fs for the Photochron IV synchroscan-camera. Techniques to further enhance this performance and extend synchroscan operation further into the sub-picosecond domain will be outlined.

The age of scientific and technological revolution sets forth the study of high speed processes as a most vital task. Further progress in science and technology and increase of production efficiency are largely dependent upon the use of high speed processes and machines and mechanisms capable of dealing with them.

The film-clawing mechanism in a 300 f.p.s. intermittent camera developed by us is a five-linkage mechanism, an eccentric adjustable loop is added to the rear hinge of the linkage for the double-crank mechanism.

Model XGS-12 high speed motion-picture camera is a new type of 16mm rotating prism camera with high quality. It has been recently developed by our institute. It has optional accessories. The maximum frame frequency of the camera. is 11000fps when one frame size is 7.5 x 10.4mm2. In this paper, three systems of this camera will be introduced, i.e. optical system, mechanical system and electronic control system. 16mm rotating prism camera has become one of indispensable instruments to modern laboratories and experiemental fields, and has widely used as measurement and analysis of high. speed phenomena quantitatively and qualitatively, being portable and cheap instrument, wide range of frame frequency from 10 to 104fps. Model XGS-12 high speed motion-picture camera. has been recently developed by our institute. It is another new kind of 16mm rotating prism. camera. Now, it is being intro duced as follows.

Synchronisation is an essential component of any high speed photographic experiment to combine the three principal components - subject, camera and lighting. Today there are many available equipments to ensure synchronisation for the current industrial and research problems but when the exception occurs, the skill of the good researcher again becomes necessary. It was not until the manufactured plates and films became available in the 1880's that high speed photography became a real tool and the early users had to solve their own timing problems. In general the early techniques were relatively simple but quite effective. Muybridge in his "Animal Motion Studies" arranged that the subjects operated the cameras by cords to the lens shutters. This was extremely effective. But a few researchers wished to look at very rapid events and needed more automatic methods. For example Mach began on photographing bullets and shells requiring timings in the microsecond range. Because he and his collaborators always took photographs and his reputation was so great, his work was always noted and assumed to be original. Some thirty years earlier, in Berlin, Toepler and Holtz under Professor Riess were working on Electrostatic Generators and Sparks which led Toepler on to his brilliant development of the Schlieren technique. His early application of this technique involved the synchronisation of two spark gaps, one as an illuminant and the other as an event such that shock waves were made visible by his Schieren system. The "pictures" in his published papers look like photo-graphs but in fact were engravings from his own drawings after viewing at least hundreds of images. His circuits and the later Mach circuits must be the earliest of our modern electronic circuits and fully deserving of our recognition.

This continuous-access rotating drum/rotating prism type camera has proved itself in the auto industry as a fixed-position instrument. The commercial version features an integrated film supply, a sector shutter and interchangeable optical and video viewfinders. The framing rate has been increased to 1000 fps.

The description of the main performance, general outline, specifications of design and application are given in this paper. Some typical pictures of test taken by this camera are presented.

This paper depicts the development and test of Model P-302 Beryllium Rotating Mirror Component used in Model WPG-30 or Model SJZ-15 Streak Camera. The mirror body is made of Hot lsostatic Pressing (HIP) Beryllium. The mirror reflective surface is made by replica film method and consists of 0.1 wave-length flatness beryllium substrate with an aluminum overcoating. Its reflectance is 83%. The cavity of the rotating mirror is not vacuumized. The rotor is strictly adjusted with the dynamic balance method. The turbine is driven by compressive-air and the maximum rotating speed in test is 5,833 rps. The size of the mirror body is 22.5X25 mmX8 mm (rotating diameter is 22.5 mm). Under examination of dynamic performance its writing rate is 15 km/s, the time resolution is 1.4 ns (0.01 mm slit width), the dynamic resolution in scanning direction is 28 line pairs/mm and the effective aperture at film is 1/10.6. The results for detonation experiments indicated that when its rotating speed was 5,000rps, the image density was suitable for measurement while using 36 DIN film. And the results also showed that the precision of measurement have been greatly improved as compared with the steel rotating mirror used before.

The general microprocessor control console described in this paper can be used for two kinds of high speed rotating-mirror camera driven by turbine or by motor. Its technical specifications, component parts and performance are expounded. The trial tests show that the control console is characteristic of high accuracy in r.p.m. measurement, stable and reliable in operation and easy to be operated and maintained.

Time synchronizing problem is an important problem in high speed photography. In order to solve this problem, a multifunctional synchronizing control system has been developed. This paper introduces structural principle of a multifunctional synchronizing control system and its applications in range test. This system is mainly applied to synchronizing photography which controls high speed cameras in measurement of trajectory and armor penetrating process, and may be also applied to synchronizing control in other time-seguential operations. This system has been used in range test to control one ZDF-50 rotating-mirror and two XG-1 slit high speed cameras, at the same time, to take pictures of 12.7mm antiaircraft machine gun bullets.

This paper deals with a new type of control system for a continuous access rotating-mirror high speed camera. New design of most circuits and the fast-open shutter of the system has been adopted. The control system has characteristics of stability and reliability, accurate controlling, and rather high integration and automation. The system has been used for Model ZDF-180 rotating-mirror high speed camera, with satisfied operational results. In the study of high speed phenomena, such as explosions and discharges, etc., the continuous access rotating-mirror high speed camera is an indispensable photographic recorder. With wide applications of high speed photographic technique, the environments where this camera is used are more complicated so the following performances of the controlling sys-tem are required to be further raised: 1. the control accuracy of the system (synchronous accuracy and measuring accuracy of photographic frequency); 2. the opening speed of the fast-open shutter, so as to guarantee enough effective recording time; 3. the ability of anti-interference. The control system is made to be more stable and reliable; 4. the improvement of performances of the system by adopting new components, so it is more handy to be operated. In order to meet the requirements mentioned above, a control system has been designed. It consists of three parts: the main control, the fast-open shutter and its control, motor control driven by the rotating-mirror. The principle block diagram and working process of the each part are introduced separately as follows:

In this paper, the results in test of high-speed rotating mirror and its applications were described. Some problems and their solvents that the rotating mirror meets at high-speed were introduced. As a result, four kinds of rotating mirror devices were given. High-speed rotating mirror device is mainly composed of rotating mirror, support system of mirror and driving system. They would be mainly studied.

In this paper the theoretical analysis of a phased roller movement is made. A numerical method for calculating kinematic characteristics of the film and a numerical method for calculating eccentric radii of the rollers according to the required working angle of the movement are introduced. The results of the calculation and the shooting experiment of a prototype camera, containing such a movement, are introduced, too.

Frition driving by elastic sleeve is a novel driving mechanism, and has been recently developed in China and other countries. FSMDES has compact mechanism, resonable pressure method and other suitable to high rolling speeding driving. Up to now, there have not been special theoretical study for this mechanism. But more heavy and complexity. It can not be used in practice calculation. So in this thesis a simple approximate calculation be deduce based on theory of bent staff for thin and thinless sleeve. In all Parameters of elastic sleeve in practice, comparaing the calculation of approximate model with the results of finite element method and theoretical method on sleeve, there are very agreement and more high precision for the approximate calculation model. This calculation model can be used to calculation the deformation of elastic sleeve in practice.

This multi-function waiting type high speed camera can be used for either waiting type or synchronizing type, it can also be used as high speed streaking, framing, shadowgraph or interference photograph. The time resolution of its streaking system is 1.75x10-7 -1.17x 10-9 sec. the steaking speed is 0.0667-10mm/psec. The framing rates of its framing system are 1-150x10 4 pict/sec and 2.25-337.5x104 pict/sec separately. The framing sizes are 14x24mmland 9.1x15.6mm2 separately. This paper descrides the features, working principle, overall design and main technical performances of the instrument.

This paper discusses several problems on the JX-300 intermittent synchronous high-speed camera developed by the Institue of Optics and Electronics (10E), Academia Sinica in 1985. It is shown that when a framing rate is no more than 120 frames/s, a relatively high reliability is obtained resulting from low acceleration of the moving elements, weak intermittent pulldown strength, low frequency vibration, etc. At the time when a framing rate increases to over 200 frames/s, the photographic resolving power, as well as the film running reliability reduce due to the dramatic increase in vibration and pulldown strenth, which is similar to that in the stationary photography. It is getting worse when the framing rate is up to 300 frames/s. Therefore, deliberating on the choice of a claw mechanism having a framing rate of over 300 frames/s and conducting a series of technical measures are particularly important for a camera to obtain a sharp object image securely, otherwise it can hardly reach the framing rate of 300 frames/s for an intermittent camera. Even if this framing rate is attained, the image quality is also deformed and the mechanism would be rapidly worn off from high vibration.

The modulation transfer function (MTF) chain of drum high-speed model GGS-1, particularly, the effect of its natural image displacement and the change of illuminant intensity on image quality are discussed in this paper.

This paper gives: (1) a detailed description of the combined characteristics and the directions for use of the combined laser high-speed camera; and (2) a brief description of the main characteristics of its constituent parts. In the last part of this paper, a special description is given of : (1) the photographic method of finding the rule of flying of the flying chips under the action of explosives by using this instrument; and (2) the related test results.

This paper is a discussion of the development and of the current state of the art in picosecond soft x-ray streak camera technology. Accomplishments from a number of institutions will be discussed. X-ray streak cameras vary from standard visible streak camera designs in the use of an x-ray transmitting window and an x-ray sensitive photocathode. The spectral sensitivity range of these instruments includes portions of the near UV and extends from the subkilovolt x-ray region to several tens of kilovolts. Attendant challenges encountered in the design and use of x-ray streak cameras include the accommodation of high-voltage and vacuum requirements, as well as manipulation of a photocathode structure which is often fragile. The x-ray transmitting window is generally too fragile to withstand atmospheric pressure, necessitating active vacuum pumping and a vacuum line of sight to the x-ray signal source. Because of the difficulty of manipulating x-ray beams with conventional optics, as is done with visible light, the size of the photocathode sensing area, access to the front of the tube, the ability to insert the streak tube into a vacuum chamber and the capability to trigger the sweep with very short internal delay times are issues uniquely relevant to x-ray streak camera use. The physics of electron imaging may place more stringent limitations on the temporal and spatial resolution obtainable with x-ray photocathodes than with the visible counterpart. Other issues which are common to the entire streak camera community also concern the x-ray streak camera users and manufacturers. Optimized spatial and temporal resolution, enhanced dynamic range, and the understanding of shot noise statistics are topics which are being worked on at this time.

The fundamental studies for the triple-flash x-ray generator having variable spectra for biomedical radiography are described. Two types of triple-flash x-ray generators consisted of the following components: a high-voltage generating unit, a voltage divider unit, three high-voltage pulsers, a triple-parallel impulse switching system utilizing air gap pulsers for the main gas gaps, a high-power gas diode having three terminals, a turbo molecular pump, and three x-ray tubes having cold cathodes. For the single-tube generator, the pulse condensers of the pulsers were charged to the same or different energies by using a voltage divider unit and were connected to the x-ray tube through a high-power gas diode. In contrast, the pulsers were connected directly to three tubes without a diode. The duration of each x-ray pulse was a few ps, and the minimum time interval between two pulses was about 100ps (single-tube type), the x-ray intensity was less than lx10-5C/kg at lm per pulse, and the effective focal spot size was determined by the diameter of the anode rod. The triple exposure of pulsed x-rays having variable spectra and time intervals was obtained.

The construction and the fundamental studies for a pulsed x-ray and charged particle beam generator used in the low photon energy region are described. This generator consisted of the following components: a high-voltage power supply, a high-voltage coaxial oil condenser of 120kV-0.2pF, a gas gap switch, a low-impedance coaxial transmission line, a turbo molecular pump, and a pulsed x-ray and charged particle beam tube. The condenser was charged from -60 to -100kV and was connected to the radiation tube through a gas gap switch. The electric charge stored by the condenser was discharged to the radiation tube when the gas gap switch was closed. This radiation tube produced pulsed (flash) x-rays through copper foil anodes. The charged particle beam was produced by the ionized air outside of the anode window due to the production of a high dose rate of x-rays, and these charged particles were accelerated by the electric field between the anode and ground. Both kinds of radiation were produced simultaneously, and the migration time of the charged particles corresponded to the duration of the pulsed x-rays.

A repetitional pulsed x-ray generator in conjunction with an image intensifier system for biomedical radiography is described. This generator consisted of the following components: a high-speed power supply, various capacities of pulse condensers, a turbo molecular pump, and an oil-cooled x-ray tube. The pulse condensers were charged to the optimum voltage of less than 100kV, and the electric charges were discharged repeatedly by using the flashover mechanism. The pulse width tended to decrease when the capacity and the anode-cathode(A-C) space were reduced, and their values were less than 200ns. The current of the power supply determined the repetitional rates for the pulses, which were limited by the charging resistor, the condenser capacity, the charging voltage, and the electric power of the power supply. The maximum value was less than 20Hz due to the ripples of the charging current of 50Hz. The x-ray quality primarily became hard by increasing the charging voltage, and inserting metal filters. The effective focal spot size primarily varied according to the diameter of anode tip, and its size was less than 3.0mm in diameter. Pulsed x-ray fluoro-scopy was performed by using an image intensifier system utilizing a CRT for medical use.

1GW iodine photodissociation laser beam (λ= 1.315pm) is focused to generate continuum X-ray radiation at a titanium (Z=22) target. A piece of aluminum (360Å) on mylar (8μm) film is used to isolate the soft X-ray emitted. Convex - curved mica (2d002 = 19.84Å) crystal spectrometer is used to obtain soft X-ray spectra and the slope of continuum X-ray spectra ( λ < 20Å) are found to show two different effective electron temperatures, 0.11 KeV and 7.1 KeV and we conclude there are two electron groups in the iodine photodissociation laser produced titanium plasma.

In this article we describe the project of a Modern Flash Radiography System being constructed by our Institute. Its main characters are: (1) The Marx Generator for nanosecond pulse has modular construction, similar to products of Hewlett-Packard Company of American, to improve the stability. (2) The inductance of the Marx circuit has been reduced, so the output voltage of this Flash Radiography System will be raised and its volume will be reduced. (3) Multi-stage triggers have been used, which will extend the trigger range of gap switch. (4) Flash X-ray Tube with multi-tip explosive cathode have been manufactured, it will improve dose and life of Flash X-ray Tube. The performances of this improved equipment will catch up with and partially surpass the performances of products of Hewlett-Packard Company.

A flash radiographic system utilizing a single flash x-ray generator having a new kind of combined x-ray tube and a computed radiography (CR) system is described. This system consisted of the following components: two types of delay switches (i. e. (a) direct switching and (b) laser switching), a delayed pulse generator, a CR system, and a high-intensity single flash x-ray generator. This generator consisted of the following components: a high-voltage generator, a high-voltage pulser, a vacuum pump, and a new type of combined remote x-ray tube with two sets of anode and cathode electrodes. When the radiographic object triggered the timing switch, a short electric pulse was produced and was transmitted to the delayed pulse generator. An accurate delayed flash x-ray was produced when the delayed pulse was transmitted to the high-speed impulse switching system inside of the high-voltage pulser. Next, when the radiographic object was exposed to the controlled x-rays under the optimum radiographic conditions, the permeating x-rays produced the digital image. The FX pulse widths were less than 10Ons with a photon energy of less than 120keV. Since the time resolutions for the two types of delay switches were less than 2Ons, the total time resolution for the FX production was less than 1ps. Various kinds of high-speed biomedical radiography, e. g., the continuous delayed radiographs and the continuous three-dimensional analysis could be performed by controlling the radiographic conditions.

XIOPM was founded by Academia Sinica in 1962. The main goal of the Institute is developing some optical and opto-electrical diagnostic tools of transient phenomena. The paper describes the activities of the Institute on developing various opto-mechanical high speed cameras, image converter tube high speed streak and framing cameras, high speed holographic cameras and other high speed cameras and the achievement acquired since its foundation.

As shown in [ 1, 2] , the use of a microchannel plate (MCP) as an electromagnetic radiation photoreceiver has certain advantages over the use of semitransparent metal photocathodes. First, MCPs feature a significantly higher level of radiation conversion, particularly in case of hard quanta. Second, the spectral sensitivity range of MCPs is much wider running from vacuum ultraviolet to the 17-domain. These properties make an image converter tube (ICT) with an MCP photocathode a promising device for registration of high speed processes in a wide spectrum range.

An X-ray image converter tube, type PRM-V, intended for registration of soft X-ray radiation in the 0.5 to 10 Å range has been designed.

In this paper, the principle of the synchroscan streak camera will be discussed based on the Bernuli Theorem, and its equation of detection and the minimum detectable threshould of input light power density will be derived according to the theorem of noise. The limited time resolution of this kind of camera will be dealt with in terms of the method of probability and mathmetical statistics theoretically and it will be estimated with Monte Carlo method accurately. According to above theoretical analysis, the relevant parameter relationship of this kind of camera will be established quantitatively, which will show how to improve the performances of this camera effectively. The calculation results will show that its minimum detectable threshould of input light power density is in the order of 10-12w/mm2 and that its limited time resolution can be better than that of the single-shot streak camera by improvements of stabilities of the CPM laser system and its relevant streak circuits.

A measuring system of instantaneous optical spectra with an image converter tube was described in this paper. The system consists of a wide-band and high-transparent objective lens, the Model WDG-30 spectral head with plane reflection gratings and the Model JTG-305 image converter framing/streak camera. The design consideration of the system, the image converter tube and its control as well as main characteristics of the system were presented.

This paper mainly deals with the present status of the development of nanosecond image converter framing cameras and nanosecond double-proximity image intensifier framing cameras in our country, and discusses shutter pulse generator circuits of these cameras. 1-2 The mixing circuit consisting of avalanche transistor series and pulse thyratron maintains strong anti-interference. Its trigger delay time is 14ns, the trigger jitter is about :500 ps, the shortest output pulse width is 15ns, its amplitude is 550V and the pulse spacing is 150ns. The circuit consisting of avalanche transistor series and rapid restorer diode has 300v of output pulse amplitude, lOns of pulse width and 5Ons of pulse spacing. It is suitable for a new type of image converter tube which is not strict with pulse waveform. But, the strobe circuit of multichannel double-proximity image intensifier camera can provides 2ns of pulse width, 2ns of pulse spacing and -300V of amplitude. When it is used with double-proximity tube, this kind of strobe circuit can obtain a dynamic resolution of better than 4.71p/mm. When it is used for MCP-PMT ns pulse generator, its largest synchronous pulse frequency is 30 kc; pulse width is 4-40ns; adjustable amplitude is 200-300. These circuits can be used for controlling low-light silicon target pick-up tubes, for testing high voltage electric device characteristics, for ns pulse source and laser modulation by improving them slightly. The existing ns image converter framing cameras are limited in their applications, since their framing rates can not be high enough to satisfy the requirements for measuring tran-sient phenomena. In 1982, we developed a ns ring-shaped grating image converter framing camera with an exposure time of 15ns and a frame spacing of 150ns. The reason why these data indexes are not high enough is that the ring-shaped grating image converter tube is very strict with the front and back edges and the flat-topped oscillation of the shutter strobe pulse waveform added to the control-grating of the ring-shaped grating image converter tube. The time of switching devices selected as gate pulses can not be very short. The switching devices are in a state of big current pulse discharging, the restoring time of the tube is longer from leading to stopping, so it is difficult for several gate pulses to form rather short spacing and steep-front and back serial pulses on the same common load. Thus, the dynamic space resolution of the image converter tube does not meet the applied requirements because of the poor gate pulse waveform. The gate pulse generator switching device in this kind of framing camera adopts a mixing circuit consisting of the avalanche transistor series and the pulse thyratron (Fig. 1). The output pulse amplitude of this circuit is 550V, rising edge: 2.5ns, falling edge: 4.5ns, trigger delay: 14ns, jitter: 500ps. It adopts low impedance matched output. As the circuit has advantages of short trigger delay, little jitter and strong anti-electromagnetic interference ability, the satisfied results have been obtained in the test of once-through strong electromagnetic interference.

The term "ballistic detonics instrumentation" is generally applied to all physical observations that occur in connection with the detonation of conventional high explosives. The reaction and/or detonation velocities are of the order of 1000 m/s to 9000 m/s, at pressures of several hundreds of kbar. In order to obtain records or pictures of a detonative event with little motion blur and high time resolution, exposure times of less than 10 ns and frame rates higher than 106/s are desirable. About one or two decades ago, new discoveries and improved knowledge in the field of detonics were heavily dependent upon developments in high speed photography. Nowadays, however, special cameras are available for diagnosing detonation phenomena and events involving high pressure and shock waves, and their commercial development has produced reliable and easy-to-use instruments. Thus, the scientist working on ballistic detonics problems can now concentrate on developing measuring techniques instead of developing measuring instrumentation. A short overview will be given of the different most used and important optical equipments and cameras in the field of ballistic detonics instrumentation. Furthermore various examples of sophisticated, and even "tricky", configurations for optical high-speed mea-surements in the field of ballistic detonics diagnostics will be shown.

The model BY-90 high speed raster motion picture camera was designed and manufactured by authors in 1986. The raster plate that was adhered together by two plates of plano-convex cylindrical lenses has been used. The images were moved by the rotating Nipkov disk. The range of framing rate is from 1000 fps. to l5x10 4 fps. and maximum frame number is 300. It has an electro-magnetic shutter, the control systems consist of model TP-801 micro-computer and other parts for measuring the framing rate, digital display and the shutter release synchromization. On the basis of above-mentioned camera, a new type camera was designed. We have also redesigned the mechanical scanning field in a square shape instead of the circular field. The practical field of square microlenses can be more effeciently used, thus the operating characteristic of this type camera will be improved further.

A new stroboflash photographic system has been developed. The photographic device is a SLR camera with a motor drive, the stroboscope consists of eight strobo-tubes and control circuit. The flash color, flash rate and the flash duration can be changed rapidly by micro-computer on line, so that it is available to measure the track and parameter of moving object. Low cost and versatility is the advantage of this system.

High dynamic performance is required for a cilletheodolite which provides high speed and acceleration tracking and high speed photo-recording and measuring simultaneously,with the development of superfast iissue and the requirelient of measuring at short slant distance. In order to track such fast targets, angular velocities beyond several radians per second and accelerations beyond several radians per second squared are required at the tracker's axes. It is difficult for conventional configuration to achieve high tracking acceleration while keeping small size and unexpenive price. A new type firror tracking system was developed by photosonics, In in 1971.1

In 1938, Steenbeck et al.1 succeeded in constructing the first generators capable of delivering intense X-ray pulse. The generation of X-ray flashes, especially with respect to efficiency and reproducibility, was achieved by W.P. Dyke and co-workers who were mainly concerned with field emission and its application for the production of X-ray pulse. These efforts eventually lead to the development of technically superior and commercially available flash X-ray devices which are now in use throughout the world for mainfold purposes. In scientific technological field, the flash X-ray radiography has long been known as an useful radiation source for the investigation of high speed phenomena and has been widely applied. The first part of this paper mainly introduces the work about flash X-ray radiography in China. That includes: flash X-ray radiography system, portable pulsed X-ray system and powerful pulsed X-ray sources. These equipments have been widely used in the fields of ballistics, detonation and biomedical studies. In the 2nd part, it mainly, describes the developments about flash X-ray radiography in the part of the world which includes: flash radiographic biomedical studies, X-ray pulse generators of high repetition rate, tomograpy and other applications.

The paper describes a new and novel video system which combines real time operation at 378 TV line resolution with the ability to capture, on command, a single high resolution 850 TV line image. The camera system incorporates a high resolution image tube giving shuttering periods as short as 200ns. The resulting photographic quality images may be dumped from the digital frame store to a hard copier or transferred to a PC for image enhancement.

Flash x-ray radiography with single pulse has been developed about fourty years. It is widely used to study instantaneous phenomena. Comparatively speaking, the flash x-ray cineradiography is a kind of advanced techniques. Especially the flash x-ray cineradiography using a single flash x-ray tube and generator is now in the ascendant. In this articale, the recent progress including principle, construction and application of the flash x-ray cineradiography at home and abroad, especially with single x-ray tube and generator has been described. It contains four sections: (1) Introduction; (2) Choice of the storage capacitor; (3) Charging and quenching; (4) Conclusion

The use of metal-halide lamps, with 4 times as much light output in comparison to conventional tungsten halogen lamps, has rapidly grown for high-speed-film use. Lamps range from 200 to 12 000 W. The color temperature will match perfectly with the requirements of daylight film. In combination with various high specialized optical luminaries and systems, the lamp shows outstanding performance and allows new applications. As the metal halide lamp is an AC-discharge type, a special power supply is necessary to overcome the the flicker effect. Electronic power supplies (EPS) with a square wave current characteristic allow flicker free films up to min. 8000 frames per second. Meanwhile the 3rd generation of EPS's will be introduced, which perform with even increased electric stability, compact size and decreased weight. This paper contains the practical uses in the field and possible future applications. Finally it gives a preview on future design and technologies.

A new photographic technique to measure the velocity of small particles flying at high speed has been developed. A pulse Ruby laser and an optical fiber system are employed for taking a double exposed photograph in a very short time interval. The delay time is precisely determined by setting the fiber length, then the accuracy of velocity measurements is mainly influenced by the measurements of moving distances of particles. This new technique is applied to observation of diesel fuel spray, and the usefulness of the technique is confirmed.