Double Exposure Method Research Articles

２こま撮り高速度ホログラフィシステムの開発

A new twin-pulsed high-speed holography system which can record two frames continuously, was developed for the recording of high-speed phenomena with high temporal resolution. Two phenomena which occur at different time are recorded in one hologram, and after photographic processing, the images of the phenomena can be reconstructed independently. Using this system, diesel fuel injected into the open atmosphere was recorded, and spark ignition of fuel gas was also recorded by double-exposure holographic interferometric method.

Estimating viability of plant protoplasts using double and single staining

The utility of numerous dyes for determining the viability of barley (Hordeum vulgare L. cv. Himalaya) aleurone protoplasts was studied. Protoplasts isolated from the barley aleurone layer synthesize and secrete α-amylase isozymes in response to treatment with gibberellic acid (GA) and Ca2+. These cells also undergo dramatic morphological changes which eventually result in cell death. To monitor the viability of protoplasts during incubation in GA and Ca2+, several types of fluorescent and nonfluorescent dyes were tested. Evans blue and methylene blue were selected as nonfluorescent dyes. Living cells exclude Evans blue, but dead cells and cell debris stain blue. Both living and dead cells take up methylene blue, but living cells reduce the dye to its colorless form whereas dead cells and cell debris stain blue. The relatively low extinction coefficient of these dyes sometimes makes it difficult to distinguish blue-stained cells against a background of blue dye. Several types of fluorescent dyes were tested for their ability to differentially stain dead or living cells. Tinopal CBS-X, for example, stains only dead cells, and its high extinction coefficient allows its ultraviolet fluorescence to be recorded even when preparations are simultaneously illuminated with visible light. To double-stain protoplasts, the most effective stain was a combination of fluorescein diacetate (FDA) and propidium iodide (PI). By employing a double-exposure method to record the fluorescence from cells stained with both FDA and PI, dead and living cells could be distinguished on the basis of fluorochromasia.

Application of Laser Hologram Interferometry to the Distortion Determination of Sugar-Coated Tablets

AbstractSugar-Coated tablets of different core materials were prepared and the degree of distortion of the sugar coat was determined by the laser holographic interferometry of double exposure method. It was found that, as the degree of expansion of the tablet core material increased, the sugar coat became more distorted. By the present method, nondestructive measurement of a minute amount of distortion is possible and thus superior to conventional methods.

Developing an operational radiographic inspection method for the elbow-shaped branch pipes at the NPP working with RBMK-1000

The effect of radiation background on the results of radiographic inspection was studied using the double exposure method. The radiographic film was exposed to create an artificial fog. The authors used slotted, wire, and sheet specimens as the sensitivity standards which were mounted on a 8.0-mm thick 1Kh18N9T steel plate facing the radiation source. The conducted studies showed that when the series-produced GII-D-3 gamma-ray sources having an activity not less than 40.2 X 10/sup 10/ Bq and RT-1 radiographic film are used, it is possible to accomplish radiographic quality control of the welds of the elbow-shaped branch-pipes under the conditions of a radiographic background of 1000 ..mu..R/sec and within the confined space below a RBMK-1000 reactor.

Splitting of the electronic intrasite transitions of beryllium in germanium

The interferometric method of Nisida and Saito, the absolute retardation method of Post and the double-exposure holo-interferometric method of Hovanesian, Brcic and Powell are correlated and shown to give identical fringe patterns as regards intensity. Various discrepancies in Nisida and Saito's interpretation of their fringe patterns are pointed out, and the simultaneous presence and relative predominance of isochromatic and isopachic half-tones are discussed. The principles of photography and the concept of half-tones are used to explain the formation of concomitant isochromatics and isopachics and to give a new interpretation to these fringe patterns.

Mechanical reactions of facial skeleton to maxillary expansion determined by laser holography

The highly accurate laser holographic interferometry method was used to determine in what way low-magnitude forces during slow maxillary expansion are transmitted to the entire maxillary complex and its surrounding structures. The experiments were carried out on a macerated human skull which had a perfectly preserved, normally aligned maxillary dental arch and intact alveolar processes. The soft palatal and periodontal tissues were reconstructed with a semielastic material. The specimen was loaded gradually by widening of a split acrylic appliance with an expansion screw. Interferograms were taken simultaneously on the left and right sides of the maxillary complex, using the 10 mV HeNe laser and the double-exposure method. Analysis of the fringe pattern on the recorded object surface was performed by graphically determining the deformation curves related to the bony surface in selected horizontal and vertical planes. Experimental results show that the application of laterally directed forces from the maxillary expansion appliance induced initial mechanical reactions of the entire maxilla, the circummaxillary sutures, and the surrounding bones. Each increase in dental arch width was obtained not only by the deformation of the alveolar process with dental tipping but also by the rotation of the entire maxilla within its sutures around horizontal and vertical axes. Moreover, displacement of the surrounding maxillary structures (pterygoid processes, zygomatic, lacrimal, and nasal bones) was detected in response to the rotational movement of the maxilla.

Thickness contours of highly aberrant phase objects. I. Reduced sensitivity holographic interferometry for direct phase measurement

A double-exposure holographic method is described that permits one to visualize thickness contours of highly aberrant thin phase samples. The hologram is recorded using a reference wave that bears a simple phase relationship with the subject wave while the reconstruction is made with a plane wave. The phase shaping of the reference wave is accomplished by making it traverse the test sample. If the test sample is thin and the hologram is recorded in the plane in contact with its rear surface, the phases of the hologram producing waves are correlated to each other at all points through a constant. Consequently, the reconstructed object wave contains direct phase variations of the object at reduced sensitivity, which can be varied by changing the hologram recording geometry. A double-exposure technique has been used for the vizualization of the phase variations of the object wave. Furthermore, a finite distance between the sample and the plane of the hologram produces a lateral shearing interferogram receiving variations of the phase gradients of the object. The method is applicable to thin samples that do not have high, rapidly varying surface deformations.

IBM system designs from scratch: Electronics p. 93 (14 July 1981)

Two SR steppers, SS-1[1] and SS-2, are used at the NTT SR facility to accelerate the development of LSIs with a feature size of 0.2 microns or less. This paper presents the compatibility of the two SR steppers focusing on overlay accuracy. For stepper to stepper overlay, repeatability and offset controllability are the important factors. The stand-alone overlay repeatability of ±30nm, and offset control resolution of 10nm are achieved. The difference of run-out error between two beamlines, which have an adverse affect on compatibility, are measured. It is less than 60nm in 18mm square. The influence of chucked wafer flatness to overlay accuracy is clarified by experiments and simulations. The overlay accuracy of 60 nm(3 σ) for the two SR steppers is obtained by double exposure methods using the same mask and alignment marks formed by a photo stepper. These two steppers are now being applied to test device fabrication.

Deformation Measurement of Dental Impression Materials using Holographic Interferometry

Holographic interferometric technique by a general double-exposure method has been used to measure the deformation of many kinds of things. A specific optical system as a kind of application of this technique is devised to measure only vertical deformation of dental impression materials. The results of the measurement of the time dependence of one directional deformation during or after the vulcanization of four kinds of elastomer impression materials are shown. These results show clearly that this technique is very useful for the analysis of deformation of dental impression materials.

Detection of small displacements of diffuse objects illuminated by a speckle pattern

The detection of axial displacements of an object imaged with a laser beam on to a photographic plate is not easy because the aperture of the imaging system is not generally large and the variation of its impulse response with the defect of focus is then relatively slow. We propose here a double-exposure method in which the object is illuminated under a large angle of incidence θ by a random beam which is generated by a laser-illuminated ground glass. After the first exposure, the object undergoes an axial translation ϵ and the photographic plate is laterally displaced. ϵ is small and we can assume that this axial translation results only in a lateral displacement ϵ tg θ of the incident amplitude from the ground glass. Under these conditions, the two intensity distributions recorded by the photographic plate are no more identical and the contrast of the Young's fringes observed in the Fourier plane of the photographic plate is a decreasing function of ϵ.

ホログラフィによる工作機械構造の3次元変形測定

The static, thermal and dynamic deformations of the machine tool structure are measured by means of holography. The whole optical system for laser holography is placed on the heavy reinforced concrete block supported by several air cushions. The double exposure method is used in the static and thermal tests, while the time average method is used in the dynamic tests to obtain the mode shape and vibration amplitude of the structure at a resonance frequency. The transient thermal deformation of the structure is evaluated by taking the interference photographs at a certain interval during the cooling-off period of the structure and by assembling these results in the preceding intervals. Holography is also proved useful to examine the mechanical behaviors of the machine interface.

Flow visualization by an improved double exposure method in holography

Some optical differential interferometric techniques were investigated in order to measure the density distribution in the air jet flow of a small scale flow cell while excluding the effects of the optical distortion of its glass windows. A technique using moiré fringe formation by rotating the reference wave in one exposure of the double exposure method was found to be most suitable for this purpose. High contrast and multiplication of moiré fringes can be obtained by a moiré fringe sharpening and multiplication method.

A new interpretation of interferometric fringe patterns

The interferometric method of Nisida and Saito, the absolute retardation method of Post and the double-exposure holo-interferometric method of Hovanesian, Brcic and Powell are correlated and shown to give identical fringe patterns as regards intensity. Various discrepancies in Nisida and Saito's interpretation of their fringe patterns are pointed out, and the simultaneous presence and relative predominance of isochromatic and isopachic half-tones are discussed. The principles of photography and the concept of half-tones are used to explain the formation of concomitant isochromatics and isopachics and to give a new interpretation to these fringe patterns.

A triple-exposure technique to reduce recording time in stroboscopic holographic interferometry

A triple-exposure technique is suggested which reduces the pulsed recording time in stroboscopic holographic interferometry to one half of the required in the corresponding double-exposure method. It has also been found that monitoring of ht ebright reconstructed fringes is easier in the suggested technique.

A laser interferometer for combustion, aerodynamics and heat transfer studies

A large-area interferometer is described which is based on schlieren system and designed to be used subtractively by a double exposure method. The beam is split using front and rear surface reflections from a small-angle prism. On the double exposure interferogram both the fringe spacing and shear are variable. The aim is to subtract not only aberrations and windows, but principally end-effects, which otherwise introduce disproportionately large errors in the study of hot test objects. To this end burners and heated pipes of different lengths, but identical in every other respect, are used. Various methods of subtraction are discussed and illustrated by examples taken from a study of the effect of electric fields on heat transfer from flame gases.

Holographic Measurement of General Forms of Motion

An equation describing the reconstructed holographic images of objects in any state of motion is obtained starting from consideration of the effect of motion on coherence. The equation explicitly shows the dependence of the reconstruction on both the total displacement and the form of the law of motion. Applications to the measurement of motion for the special cases of vibration, constant velocity motion, and their combination are presented together with several experimental results. In particular the theory is shown to be valid for both double exposure and time average exposure methods of displacement, distortion, and vibration analysis.

X-Ray Measurement of Stress by the Double Exposure Method

There are two ways to measure stresses by means of X-rays, namely the counter method and the photographical method. There is tendency in recent years that the counter method has been gradually being employed in laboratories and factories because of its affording possibilities of easy handling and quick measuring. It is well known, however, that the photographical method has hither to been more frequently applied than the counter method to the measurement of residual stress on local and small positions. There are several difficult problems about the measuring technique of the conventional photographical method, for example, the difficulty in powdering the specimen surface with calibrating material and the difficulty in determination of peak positition on the broadened diffraction lines, since the distance between the diffraction lines from the specimen the calibrating material is close on the film.In the present study a new method of determining X-ray stress from this point of view by the photographical method without using calibrating material has been tested and those features are mentioned. The distance between the X-ray film and the surface of specimen can be precisely determined by the diameter of diffraction ring of the calibrating material which powders the specimen surface by the conventional method. Bragg's angle of specimen is obtained by using the value of the distance and the radius of the diffraction ring of the specimen. On the other hand, by a new method which is called the double exposure method, the first exposure is given on the X-ray film from which the distance to the specimen is l1, and when the distance between the specimen is set at l2, the second diffraction ring of the specimen is photographed. Bragg's angle 2θ is calculated from Δl, the difference between the distance l1 and the distance l2, and Δr, the difference between the radius r of the diffraction rings at the first and second exposures, as 2θ=tan-1[-Δr/Δl1].As was expected, it has been made clear from the theoretical and the experimental discussions that this double exposure method has many advantages as follows:(1) If the difference between the radius of both the diffraction rings, Δr, is larger than a quarter of diameter of the diffraction ring of the specimen on the conventional method, the accuracy of the measured value of stress by the double exposure method is better than that by the conventional method.(2) The two diffractions forming the similar patterns, the distance between the peaks of diffraction intensity curves, have been easily measured.(3) Irradiation of X-ray beams can be easily pointed at the measuring position on the specimen without using the metallic powder as calibrating materials.(4) There is a difficult problem in measuring by the conventional method, the stress on the specimen with broad diffraction lines, because these diffraction lines of the specimen interface with those of the calibrating material. In contrast with above mentioned case, the stress measurement of such a specimen is made possible by employing this double exposure method.

Diagnosis of Pes Planus by X-Ray

Because of numerous complaints relative to the feet, among the Armed Forces, it was decided at this Station to conduct a survey of foot cases. Letters from officers stationed overseas led us to the conclusion that many men were being shipped out with foot conditions which caused them to become incapacitated, either partially or wholly, thus imposing a burden upon their organization and also sharply reducing their own personal morale. Men with minor symptoms relative to the feet and no gross physical foot deformity have many times been declared fully qualified for overseas duty on the basis of their particular jobs—clerks, technicians, etc.—on the ground that their work would not entail much marching or other physical stress. Owing to unforeseen circumstances, however, soldiers have often had to resort to foot marches when it had been anticipated that their movements would always be motorized. This has caused many with apparently insignificant foot disorders to manifest symptoms, ranging from those of a minor nature to incapacitation. According to Ilfeld (1), approximately 50 per cent of those appearing before the CDD Board at the Station Hospital, Camp Callan, California, came because of orthopedic complaints, and of these one-third were foot complaints. Morton (2) has estimated the incidence of pes planus at as high as 40 per cent of the population. The great need of further information regarding the condition is indicated by this figure and by the known etiologic role of pes planus in the production of legache, backache, and arthritic involvement of the knees, hips, and spine. In view of the above considerations, it was deemed desirable to set up a simple x-ray technic for examination of the feet, both in repose and during weight bearing (Figs. 1 and 2), whereby the actual position of the plantar arch and its deviation from normal could be accurately deter-mined. Accordingly, a simple film holder was constructed for the weight-bearing examination, and pedograms (footprints) were taken in each case, both in repose and during weight bearing, for comparison with the films. To determine the role of tarsal pronation, a weight-bearing anteroposterior view of the foot was also taken by the double-exposure method (Figs. 3 and 4). In each instance a case history was obtained with special reference to antecedent trauma and to rickets and other bone disease. An attempt was made to obtain a normal standard, deviations from which would indicate either pes planus or a pre-pes-planus status. Before describing the actual method of measurement and presenting the results of our survey, a brief review of the salient features of pes planus seems pertinent. Etiologic factors in pes planus include heredity, static defects, infections, occupation, obesity, posture, and injury. Heredity plays an important role and, according to Lewin (3), the paternal parent is usually the one responsible.