High Speed Photography and Micrography

High Speed Photography and Micrography

J. S. Courtney-Pratt

A brief review is given of those methods of high speed photography that are or may be useful for micro-graphy. When we try to record an event at a high lateral magnification, the image is moving muchfaster than the object, so that exposure times must be proportionately reduced. Moreover, at high lateralmagnification, the available light flux per unit area of the photographic emulsion is in general much less.These two effects make high speed micrography the most difficult branch of high speed photography. Insome ranges of speed and magnification, relatively conventional equipment is adequate, but there is nosingle technique that will do all that we want.

In many problems in research and industry today, itis necessary to take pictures with a very short exposuretime to study what is happening, or to see how certainkinds of fault occur, or to see whether equipment isbehaving as it should.

If we were photographing, for example, a car travelingfast, we might need an exposure time for any frame be-tween 0.01 see and 0.001 sec. The exposure that isneeded is dictated partly by the speed of the car, andpartly by the relative size of its image in the camera.Suppose the car was traveling at 100 mph and that itwas 75 yards (68.58 m) away. If we had a camera thattook pictures of the same size as professional 35-mm inecameras, each frame would measure 16 mm X 22 mm.With a 6-in. (15.25-cm) focal length lens, the image ofthe car would be about half as long as the frame, andthe speed of the image relative to the emulsion wouldbe 1/450 of the speed of movement of the car. If, todetermine the detail we want, we decided that the imageblur should not be more than 0.1 mm, we obviouslywould need an exposure time as short as 0.001 sec. Ifthe car was more distant or moving toward the camerarather than across the line of sight, the exposure timewould not need to be so short. Figure 1 shows threesuccessive frames of a racing car traveling at speed.The picture is of high quality and acceptably free fromblur, both with respect to the car and to the back-ground. This picture was taken at the ordinary rate of24 frames/sec, and with an exposure time for eachframe not much shorter than 0.01 sec. It is because thecar is a large and relatively distant object that we getsharp pictures at normal exposure times.

Suppose, however, that we wanted to study the de-formation of the tread of the tire. A possible waywould be to make a section of the roadway out of glassand to photograph the car as it passed over the top.

The author is with Bell Telephone Laboratories, Inc., MurrayHill, N. J.

Received 22 September 1964.

The tread pattern on tires in ordinary use may havedetail to be examined that is only a few tenths of aninch across. We would need to take pictures at near-natural size rather than reduced by a factor of 450,thus the rate of movement of the image in the camerawould be 450 times faster. The exposure time that wewould need would have to be 450 times briefer.

High Speed Micrography

The extraordinary shortness of the exposure that isneeded when we begin to study fine detail is indeed ageneral problem. It is aggravated when we considerthe problem of taking pictures through a microscope.In a typical example, an insect's foot can move at oneor two ft/sec. Suppose we wished to study the legmovement of a fly. We might wish to magnify animage of its foot say a thousand times and so the imageon our film would be moving (intermittently) at speedshigher than 1000 ft/sec. To keep the blur on the filmto the same figure as before, i.e., 0.1 mm, we wouldneed an exposure time shorter than 0.3 X 1-7 sec.

Again, we think of the movement of the column ofmercury in a thermometer as a slow process. In aclinical thermometer there is a constriction just abovethe bulb, so that after taking a patient's temperaturethe top of the column of mercury remains at the maxi-mum height, even though the temperature of the bulbdrops, and the bulk of the mercury contracts within thebulb. A number of suggestions had been put forwardto explain the way in which the mercury column wouldbreak at the constriction. These explanations allseemed rather unsatisfactory in one respect or another.Some years ago, R. McV. Weston decided to study theproblem in more detail. To overcome the awkwardrefraction due to the cylindrical curvature of the glassstem, he had flat surfaces ground on the sides of thethermometer. This made it possible to examine theconstriction with a microscope. To his surprise hefound that even when the mercury was expanding

November 1964 / Vol. 3, No. 11 / APPLIED OPTICS 1201

Fig. 1. Racing car driven by Stirling Moss traveling at highspeed. Repetition rate, 24 frames/sec; linear magnification '/50;

exposure time/frame 0.01 sec.

there was not a continuous thread of mercury throughthe constriction. As the temperature in the bulb rosethe mercury was pushed into the convergent part of theconstriction. The curvature of the mercury surfacebecame greater and the pressure in the bulb, to over-come the surface tension effects, correspondingly in-creased. After the pressure had reached a value suf-ficient to force some mercury past the narrowest part ofthe neck, a globule of mercury would be shot rapidlyfrom the narrowest part of the neck out into the parallelpart of the bore of the stem of the thermometer. Therate of movement of these globules was not tremen-dously high, but they would travel a distance as greatas their own diameter in a very short time, and to fol-low these movements it was necessary to use cinecameras working at rates of about 3000 frames/sec.Even so, one can barely see the movement of the drop-lets; but one can follow the early stage of their forma-tion and can form some estimate of their speed andfrequency. The whole of this phenomenon has been

elucidated by this elegant series of high speed pictures.Three successive frames from one of the records arereproduced in Fig. 2. One can see the stages in theformation of the droplet, and the deformed surface ofthe column of mercury after the droplet has crossed thegap.

When we are studying faster phenomena such asdetonation, explosion, deflagration of solid and liquidpropellants, the atomization of carburants, the grindingor cutting of metals, the penetration of armour plate,the formation of electric sparks, the "explosion" of athin wire by a surge of current, the fracture of brittlematerials, the vibration and fatigue of metals, theformation of shock waves, the ablation of hypersonicprojectiles-to name but a few examples-the rates ofmovement are much higher and the significant detail isoften just as small. In such cases, it is even morenecessary to make use of sophisticated and ingeniousforms of camera.

Limitations on the Speed of Cameras

It is necessary to apply research and developmentefforts to the improvement of cameras, for it is notpossible to continue increasing the speed of operationof a camera simply by increasing the speed of movementof the parts. Standard 35-mm cine cameras can beincreased in speed to about 200 frames/sec, but if wetry to go faster with these intermittent movementcameras the claw tears the film. If we are prepared toput up with smaller pictures, we can increase therepetition rate. The resolution measured in line pairs/mm may be no worse, but with the smaller format theresolution in line pairs across the whole frame will prob-ably be lower, and the information content of eachpicture will be less. For example, we can achieve aspeed of 400 frames/sec with a conventional 16-mmcamera which stops the film while each frame is taken.However, the over-all resolution of each frame (mea-sured in line pairs across the frame) is less than half ofthat of the 35-mm camera mentioned above.

A big advance in speed is possible if, instead of tryingto stop the film while we take each picture, we move thefilm continuously and introduce some form of imagemovement compensation so that the image and thefilm move along together during the exposure. Thebest known of the methods of image compensation isthe use of a rotating block of glass. Such a cameramoves the film continuously through a gate and rotatesa small block of glass between the lens and the film.Figure 3 shows how this principle works. A Fastaxcamera can take pictures on 16-mm film, each of whichis 10.4 mm X 7.5 mm, at a rate of about 10,000/sec.It can take pictures half this height twice as fast.*

* There is an extensive literature on the design and use of rotat-ing prism cameras, and in any survey of that field one would wishto pay tribute to the pioneer work of John Waddell. However, inthis present paper on high speed micrography, the author has notincluded a general bibliography on rotating prism cameras, asthat work is covered better in the books on high speed photo-graphy.2 4 6' 84

1202 APPLIED OPTICS / Vol. 3, No. 11 / November 1964

//

4C

/ /n

B ///

F

D-Ed/

Fig. 2. Fastax recording of movement of globule of mercury through constriction of clinical thermometer. Repetition rate, 3000frames/sec; magnification, 70 X. A, mercury in bulb; B, mercury in stem; C, constriction; D, globule forming, E, globule de-

taching from mercury; F, mercury surface at rest; G, mercury surface deformed by impact of globule.

If we try to drive a camera such as this faster still, wefind that again there is a limit set to the speed by thestrength and resistance to flexure of the mechanicalparts.

Rotating Mirror Framing Cameras

If we wish to go even faster, one of the best generalprinciples is to duplicate, or actually multiplicate, theequipment. One could easily take a set of four picturesat short intervals if one arranged four cameras in a rowand triggered their shutters one after the other withshort phase delays between them. Some of the earlystudies of animal locomotion were made with a schemenot very different from this by Muybridgel 2 from 1872onward.

It is reasonably easy to set up such multiple equip-ment if one is trying to photograph a fairly distant ob-ject. However, if we wish to study something close by,it is difficult to place all the lenses and cameras suf-ficiently close together to be able to get the pictures.In any case, the pictures would be taken from somewhatdifferent viewpoints and we would have problems fromparallax. We should not be able to project such asequence to give a steady picture.

A most valuable solution to this problem was in-vented at about the same time by Miller3 and Bowen,4

working independently. They arranged a row ofcameras, each with a lens and film and all with theiraxes pointing toward one common point. Theyformed a real image of the event on a mirror at thiscommon point, and as they rotated the mirror thebeam of light pointed to the camera lenses one after theother. The mirror could be small and could be rotatedat a very high speed, and the camera lenses could befairly small and close together, so that one couldachieve an extraordinarily high repetition rate.

This kind of camera is now called a rotating-mirrorframing camera. Some very elaborate cameras workingon this principle have been built in a number of labora-tories in several countries.3 -31 Beckman & Whitley,Inc., and the Cordin Co. in the United States, and Barr &Stroud, Ltd., in Scotland, manufacture cameras of thiskind commercially. One of the Beckman & Whitley

cameras can take a sequence of 25 pictures at 1.2 X106/sec (or with half-height frames at 4.3 X 106/sec).Another can take 80 pictures at intervals of 0.7 Msec.A camera built by the U. K. Atomic Energy Author-ityIi l2 takes a sequence of 30 pictures at 107/sec. TheBarr & Stroud cameras are based on this and laterwork31 and, using interchangeable sets of lenses, cantake 117 pictures at 8 X 106/sec, 59 pictures at 4 X106/sec, or 30 pictures at 2 X 106/sec. The limit towhich you can drive a camera of this kind is again setby the strength of mechanical parts. If you drive therotor too fast, it bursts because of centrifugal stresses.

With a rotating-mirror framing camera, if we use awide-aperture lens, we need a large mirror. If thewidth of the mirror is large, we cannot rotate it at sucha high angular speed. If we use very narrow apertures,not only is it difficult to get enough light but we findthat the resolution of any picture is limited because of thediffraction of light at the small apertures. Schardin3 2

showed that it would not be possible to increase theproduct of the repetition rate and the number of linesresolved across each frame beyond a certain figure,which would depend on the strength-to-weight ratio ofthe mirror material. t

Cameras that have been made so far are still wellbelow Schardin's fundamental limit. But even so, ithas been possible with rotating-mirror framing camerasto achieve a resolution of 280 line pairs across eachframe and a repetition rate of 4.3 X 106 pictures/sec.(The product nin = 1.2 X 109 sec-i.)

Rotating-mirror framing cameras are excellent for thephotography of brilliantly illuminated events. Suchimage brillance can be achieved when photographingobjects at or near natural size. Sultanoff,3 3 for ex-ample, has been able to record a sequence of pictureswith a camera of this kind in color at sub-usec inter-

t Schardin's Fundamental Limit: for presently availablemirror materials, the product nm cannot be greater than 4 X 109sec-, where m is the number of line pairs resolved across theframe in the direction of sweep, and n is the repetition rate inpictures/sec.


A

A-

-

I i GATE

U'.8 1

*1l

GLASSSHUTTER BLOCK

j2

'1.2

CONTINUOUSLYMOVING FILM

Fig. 3. Diagram showing the principle of image compensation bymeans of a rotating block of glass. As the block turns, the imageis displaced, and, for the duration of the exposure, the image

remains in register with the continuously moving film.

vals-a really remarkable achievement. A few photo-graphs from one of his records are shown in Fig. 4.The record shows the movement of a detonation frontdown a stick of explosive, and the way that the detona-tion front crosses a gap between two sticks of explosive.

The problem of light level becomes much more dif-ficult when one tries to photograph at considerablemagnification. There are some subjects which arebright enough. Zernow and Hauver3 4 have taken aseries of pictures at a magnification (from object tophotographic emulsion) of about twenty-five times, ofthe explosion of a wire when a large surge of current waspassed through it. Figure 5 shows a few framesselected from one of their recorded sequences. Muchfurther work in the study of exploding wires and foilshas been reported since this.3 5 -40 However, for reallyhigh magnification, it is almost impossible to getenough light through a rotating-mirror framing camerato take a record.

An Image Dissection Cinemicrograph

Some years ago, the author conceived a different ap-proach to this problem.4 4 2 An ordinary microscopewas set up, but, instead of placing a photographic plate atthe image plane, two plates embossed with a large num-ber of small lenslets were put there. The lenslets couldhave been spherical, but, instead, each plate had beenruled with a large number of cylindrical lenslets. Theaxes of the cylindrical lenslets were crossed at right an-gles, and the effect was the same as if there had been an

array of spherical or point-focus lenslets. The pitchspacing between the axes of the lenslets was 0.4 mm.With a plate 5 in. square there were 300 lenslets eachway across the image plane. Each of these lensletsfocused the light that fell on it to a small point element,and a photographic plate was placed at the focal planeof the pair of lenticular plates. A simplified diagram ofthe optical layout is shown in Fig. 6. The image on thephotographic emulsion is made up of 90,000 dots, andis rather like a halftone illustration. The difference isthat these dots are all about the same size but vary indensity, whereas a halftone illustration is made up ofdots of varying size.

Because all the dots are small and spaced out fromone another, it is possible to record another picture,interlaced with the first, by moving the photographicplate sideward by the width of one dot. In a typicalcase, the point elements have a diameter that is only1/30 of their pitch spacing. Thus, by moving the plate0.0013 cm, one can record a new picture. A simpletraverse mechanism allows one to move the plate atmore than 100 cm/sec, and this means that it is pos-sible to record pictures at 105/sec with simple apparatus.If we move the plate in a direction parallel to the arraydirection of the lenslets, we will begin to get doubleexposure after we have moved a distance that cor-responds to about thirty pictures; but if we move the

1 21

13 23

Fig. 4. Selected frames of an explosion reproduced from theBeckman & Whitley camera record, taken at Ballistic ResearchLaboratories, Aberdeen Proving Ground, exposed on SuperAnscochrome color film. The number beside each frame indicatesits position in the series of 25 exposures. Exposure time for eachframe 1.2 X 10-7 sec. Repetition rate 1.2 X 106 pps. Aperturef/27. (Reproduced by courtesy of M. Sultanoff and Ballistic Re-search Laboratories, Aberdeen Proving Ground, but unfortunately

not in color as was the original.)


Fig. 5. An example of cinemicrography with a rotating-mirrorframing camera. These are frames 16-20 from a sequence of anexploding tungsten wire. A static picture of the wire is alsoshown. Framing rate 1.2 X 106 pps. A 4-,uF condenser at 2kVwas discharged through the wire, which was 0.5 in. long and 0.002in. diam. Note that one can see the development of numbers offine sprays of droplets of molten material. (Reproduced bycourtesy of L. Zernow, G. E. Hauver, and Aberdeen Proving Ground.)

plate in a direction that makes an angle of, for example,one in ten with the array directions of the lenslets, it ispossible to cover a distance ten times as far before webegin to get double exposure. It proved possible toobtain sequences of about 300 pictures with a micro-scope of this kind at rates up to 105/sec.

We might ask how this microscope would comparewith the cameras previously described with respect tothe amount of light that it will pass. We can use awide numerical aperture microscope objective. All thelight that passes through the objective falls on thelenticular plate, and all the light that falls on any onelenticulation is concentrated to a small dot. That dot isactually an image of the aperture of the microscope ob-jective (or of the projection eyepiece if one is used).Thus, the illumination of the image element is some 400times greater than the average illumination of theimage in the plane of the lenticular plate, and the micro-scope is able to operate with a very low light level. Infact, it has been used to study events at magnificationsup to 2000 times, at the full repetition rate. At presentat Bell Laboratories, work is in progress on a micro-scope which will operate on the same general principlesand which will have a resolution substantially higherthan those that have been built before. A figure of600 lines across the field each way is expected, and it ispossible that repetition rates approaching 106/sec maybe achieved. The first simple cinemicroscope of thiskind was built at Cambridge University" and thesecond model at General Electric in Schenectady.42

In typical cases, these microscopes have been used tostudy the combustion of small crystals of primary ex-plosives, the first stages of the ignition of photoflashbulbs, and the failure of fine filament wires.

We have described briefly three main types ofcameras that have been used to take sequences ofpictures through a microscope. All three will give aresolution of 200 to 300 lines across the frame in eachdimension. The best known is the rotating-prism type,such as the Fastax camera. It can take very longsequences of pictures at about 104/sec with normalframe height, and at twice this speed for half-heightframes. Image-dissection micrographs have been builtthat can record a sequence of about 300 frames at 105frames/sec. Rotating-mirror framing cameras, suchas the Beckman & Whitley Model 189, can take asequence of 25 full format pictures at a rate of just over1061/sec. Thus, we can have a long sequence at 104frames/sec, a few hundred frames at 105 /sec, or a shortsequence at 106 /sec.

To some extent one can trade resolution for framingrate, as already mentioned for rotating-prism cameras.Similarly, some rotating-mirror cameras have repetitionrates of 107 frames/sec or even more, but the framesize is then very small and the information content ofsuch pictures is lower than at the lower framing rates.In another compromise, the Beckman & WhitleyDynafax camera", 18 takes a larger number (224) ofsmallframesat much lower rates-26,000/sec maximum.

Alternatively, one can use the principle of image split-ting (i.e., using only part of a lens to form each image)and achieve some increase in speed at the expense of res-olution.4i 4i

FOCAL PLANE OF CYtiNDRICAL LENSLETSPHOTOGRAPHIC LENTICULAR PLATE CROSSED TO PROVIDE

PLATE COMBINATION POINT FOCI

ENLARIOD

PARALLEL LIGHTPRODUCES AG

ELEMENT ATFOCAL PLAN OF

COMBINATION

L NTICULAR MICROSCOPICPLATES 06JECIY L LN

ILLUMINTN

Fig. 6. Design of an optical layout for a lenticular plateimage-dissection cinemicrograph. The lens L forms the realimage I of the object 0 on the plate. Each lenslet forms an imageon the emulsion of the aperture of the microscope objective L.Sequential recording is effected by moving the photographic plate

in the direction of the arrow A.


Fig. 7. Six pictures enlarged about four times from a series taken

at 8000 frames/sec on a simple drum camera without image

compensation, using a repetitive spark source. The effectiveexposure is obviously less than 10-6 sec. (Reproduced by courtesy

of F. Frangel, Inipidsphysik, GinbH.)

It would be a great advantage in many fields of re-search if we could get more frames and higher rates andbetter resolution per frame.

Lighting

With the three main types of cameras mentionedabove, it is possible to take pictures of events that arebrightly self-luminous or that require separate illumina-tion, and that illumination can be continuous or inter-mittent. If the subject matter to be studied is itselfnonluminous, it is possible to take sequences of pictureson continuously moving film without any image-motioncompensation by using repetitive flash illumination,provided that the effective exposure duration of theflashes is sufficiently brief. Typically, in such a sys-tem, the flash duration should be less (and preferablymuch less) than 1% of the time between flashes to pre-vent film movement during the flash from reducing res-olution below an acceptable value.

Many excellent sequences of pictures, some of largeobjects and others through a microscope, have beenrecorded with such repetitive light sources and simpledrum cameras.46-6 Figure 7 is an illustration of thepicture quality that can be achieved with this method.The records can be easily examined frame by frame, but,in general, they are not suitable for motion picture pro-jection unless special precautions are taken to syn-chronize the flashes with the film perforations54 5 5

If intermittent illumination is used with rotating-prism cameras, 14-5 * the timing of the flashes of lightshould be precisely matched to the camera operation inphase and frequency. Some of the best intermediate-speed cinemicrographic work has utilized such a com-

* See also Edgerton and Carson on page 1211 (this issue).

bination of rotating-mirror camera and synchronizedflash. With image-dissection cinemicroscopes, the il-lumination can be continuous or intermittent, and, ifintermittent, the phase and frequency of the flashes arenot at all critical.

The factors to be considered in making a choice be-tween these various types of equipment underline an-other general problem in high speed photography:it is not possible to obtain a camera that has wide aper-ture lenses, runs at a high speed, records a long sequenceof pictures, works at a high magnification, and givesextremely brief exposures and a high resolution, all inthe same instrument. One has to make a compromiseand a choice. Perhaps maximum speed is required as,for example, in some ballistic studies. Perhaps thegreatest possible light gathering power is required, aswhen studying small objects in a laboratory. Perhapstwo pictures of extreme resolution will show all the de-tail necessary, and one might use simple spark shadow-graphs. For example, suppose we were interested inthe velocity in free flight of a small spherical particle.We know that the velocity cannot change irregularly,so two sharp pictures would probably give us allthe information we needed namely, an accurate measure-ment of the change of position in a given interval oftime. Many workers have used such double flash sys-tems and others have extended this to recording with ashort sequence of flashes.46 47'5559 62 In such cases,particularly with simple phenomena, one can oftenavoid altogether the problems associated with large andcomplex mechanical cameras simply by superimposingthe two (or more) exposures. This, however, adds tothe difficulties of interpretation.

On the other hand, we may not know anything aboutthe details of the phenomenon which we are studying,for example, the way that a mechanical componentvibrates and fractures. We may then need a longsequence of pictures so that we can look at thephenomenon qualitatively; high resolution may have tobe, for the moment, a secondary requirement. Also,

Fig. 8. An arrangement for using the beam from a ruby opticalmaser as a light source for photomicrography.


!

5BifI AI LI lxI~ ~.' 1 IYSMM 11! -. 5 5 5z. ~~ ~ ;fd00:SC:;:X~^Rf~~w0FP0g:SSSS~tN0vuX; IS aft ff:A st :SSS : G-rlE :l 0 ,, 6003 ASt0gMS~000007<0 AS oFz m iFig. 9. Explosivelike melting of a fuse wire taken with a Frngel drum camera and combined stroboscope and repetitive Kerr cellat 20,000 frames/sec. Exposure duration for each frame -50X 1O-9 sec. (Reproduced by courtesy ofF. Fringel, Impulsphysik, GmbH.)

after such a qualitative examination, we may need tostudy some particular aspect in great detail.

Special Techniques

There are many other ways in which we may ap-proach special problems. As just mentioned, forphenomena that are not self-luminous, we may con-centrate on the production of extremely short, brightflashes of light. Edgerton, 6 36 4 Fischer,6 5 66 t Nolan6 7

and Wooding, and Porter6 8 have produced sparks withadequate light output to record small phenomena insilhouette (i.e., by backlighting) with exposure timesless than 10-8 sec. FrUngel and Fischer at Impuls-physik, GmbH have driven a light source of the kinddeveloped by Fischer at rates up to 50,000/sec.66

In this connection, too, recent advances in opticalmasers are of great prospective importance. To studythis, the author took a number of photographs atmagnifications up to 1800 X by the flashes of light froma ruby maser.6 970 A simple diagram of this experi-mental arrangement is shown in Fig. 8. Many othershave since used Q-switched masers to obtain briefer ex-posures. For example, Hodes and Glenn7i have takenexcellent schlieren pictures of hypersonic projectileflight.

Ellis and Fourney have caused a ruby optical maserto emit regular pulses of light at frequencies up to500,000/sec.7 2 Hargrove7" at Bell Laboratories hasproduced trains of nsec pulses from a gas maser at 101pulses/sec. Such techniques open the possibility ofnew speed ranges in high speed micrography.

On some other occasion, perhaps a single picture is allthat we need, but it may have to have an exposure timeof 10-8 sec, or less. Then, it may be better to use a

t See also Fischer and Fritsche on page 1235 (this issue).

Kerr cell or an image converter tube to take a singlepicture. Recently, cameras have become availablecommercially that allow the recording of short se-quences of pictures using several Kerr cells and/orseveral image-converter tubes,7 4 and there are systemswhich use deflecting image-converter tubes to takeseveral pictures in rapid sequence on the face of asingle tube.75 Frtingel et al. have reduced the effectiveexposure time of bright repetitive sparks so that theycan record small phenomena with improved resolutionby adding a Kerr cell to their stroboscopic equipment.76

An illustration of this work is shown in Fig. 9.There is a great variety of possible methods, and

only a few of them have been mentioned here; thereis still much to be done in the development of better in-struments in this exciting and interesting-branch of ap-plied optics.

The urgent need for better techniques has been in largemeasure responsible for the International Congresseson High Speed Photography. The first of these washeld in Washington, D. C., in 1952. The second, third,fourth, fifth, and sixth in Paris, London, Cologne,Washington, and The Hague, respectively. * It is anindication of the growth of the subject that the numberand variety of papers and the number of people attend-ing from all over the world have increased remarkably.The collected proceedings of these congresses77 -82

form a valuable reference library for a rapidly develop-ing field, and they are the best supplements to the fewbooks and review articles246'5 9 63-86 that have beenpublished.

The author would like to thank all those on whose

* See Appl. Opt. 2, 570 (1963) for a report of the VIth Congressby H. E. Edgerton and page 1276 of this issue for a review of thepublished proceedings of the Vth Congress by A. E. Quinn.


work he has drawn and the editors and publishers ofthe journals in which such work has been published.In particular, he wishes to thank the editors of BellLaboratories Record, May and Baker LaboratoryBulletin, and Materials Research and Standards forpermission to reproduce in this paper material whichin part first appeared in these journals.' 9 90,91

ReferencesNote: The abbreviations HSP2, HSP3, HSP4, HSP5, HSP6 areused throughout these references to indicate the Proceedings ofthe second, third, fourth, fifth, and sixth International Congresseson High Speed Photography. The dates and publishers aregiven in Refs. 78-82 below.

1. E. Muybridge, Animal Locomotion: An ElectrophotographicInvestigation of Consecutive Phases of Animal Movement(Chapman and Hall, London, 1887).

2. G. A. Jones, High Speed Photography (Chapman and Hall,London, 1952).

3. C. D. Miller, J. Soc. Motion Picture Television Engrs., 53,479 (1949).

4. J. S. Stanton and M. D. Blatt, The Bowen 76-lens Camera,

Naval Ordnance Test Station Rept. No. 152 (1948).5. Armament Research Establishment, Handbook of the 35th

Physical Society Exhibition (Physical Soc., London, 1951), p.177.

6. B. Brixner, in High Speed Photography (Soc. Motion PictureTelevision Engrs., New York, 1954), Vol. V, p. 55.

7. B. Brixner, HSP2, p. 108.8. S. J. Jacobs and A. A. Klebba, Naval Ordnance Lab. Memo

No. 10826 (1950).9. I. Tchernyi, HSP3, p. 324.

10. E. W. Walker, HSP2, p. 91.11. U. K. Atomic Energy Establishment, Handbook of ScientifIc

Instruments and Apparatus (Physical Soc., London, 1958),p. 260.

12. E. W. Walker, HSP3, p. 133.13. Beckman & Whitley, Inc., Commercial Literature.14. Barr and Stroud Ltd., Commercial Literature.15. The Cordin Co., and Red Lake Labs. Inc., Commercial

Literature.16. M. Sultanoff, HSP2, p. 230.17. A. E. Huston, HSP4, p. 163.18. J. R. Greer, HSP4, p. 167.19. A. Skinner, HSP4, p. 172.20. S. J. Jacobs, HSP5, p. 335.21. S. J. Jacobs, J. D. McLanahan, and P. F. Donovan, HSP5,

p. 341.22. T. Uyemura, HSP5, p. 346.23. R. J. Krumhansl, HSP5, p. 355.24. K. R. Coleman and A. Skinner, HSP5, p. 362.25. A. Skinner, HSP6, p. 45.26. S. J. Jacobs, J. D. McLanahan, and E. C. Whitman, HSP6,

p. 57.27. C. H. Bagley, HSP6, p. 84.28. B. Brixner, HSP6, p. 93.29. L. H. Th. Rietjens, HSP6, p. 101.30. G. L. Schnirman, A. S. Dubowik, P. W. Kewlischwili, A. B.

Granigg, and I. A. Koroljow, HSP6, p. 107.31. A. Skinner, J. Sci. Instr. 39, 336 (1962).32. H. Schardin, HSP3, p. 316.33. M. Sultanoff and R. L. Jameson, J. Soc. Motion Picture

Television Engrs. 69, 113 (1960).34. L. Zernow and G. E. Hauver, HSP3, p. 305.35. W. G. Chace and H. K. Moore, Exploding Wires (Plenum,

New York, 1959), Vol. I.

36. W. G. Chace and H. K. Moore, Exploding Wires (Plenum,New York, 1962), Vol. II.

37. L. Zernow, G. Woffinden, and F. W. Wright, HSP5, p. 283.38. G. A. Theophanis, HSP5, p. 129.39. W. C. Goss, HSP5, p. 135.40. L. Liebing and F. FrUngel, HSP5, p. 138.41. J. S. Courtney-Pratt, HSP2, p. 152.42. J. S. Courtney-Pratt and C. M. Huggins, Rev. Sci. Instr.

28, 256 (1957).43. J. S. Courtney-Pratt, HSP3, p. 81.44. J. S. Courtney-Pratt and D. P. C. Thackeray, HSP3, p. 87.45. J. S. Courtney-Pratt and D. P. C. Thackeray, J. Phot. Sci.,

5, 32 (1957).46. W. G. Chesterman, The Photographic Study of Rapid Events

(Clarendon, London, 1951).47. P. Fayolle and P. Naslin, High Speed Photography (Soc.

Motion Picture Television Engrs., New York, 1954), Vol. V,p. 101. See also P. Fayolle and P. Naslin, PhotographieInstantange et Cingmatographie Ultra-rapide (Institut d'Optique, Paris, 1949).

48. F. Frungel, HSP2, p. 19.49. A. Stenzel and K. Vollrath, HSP2, p. 55.50. H. Luy and R. Schade, HSP2, p. 59.51. F. Frtingel, HSP3, p. 57.52. P. Devaux, HSP2, p. 43.53. H. E. Edgerton and P. Y. Cathou, Rev. Sci. Instr. 27, 821

(1956).54. F. Frtingel, HSP4, p. 104.55. F. Frilngel, Explosivestoffe No. 10, 1958.56. F. Frtingel and W. Thorwart, HSP6, p. 602.57. W. D. Chesterman and D. T. Myers, J. Sci. Instr. 28, 301

(1951).58. R. E. Wells, S. Teicher, E. R. Schildkraut, and H. E. Edger-

ton, J. Soc. Motion Picture Television Engrs., 73, 627(1964).

59. H. E. Edgerton and J. R. Killian, Flash! (Branford, Bos-ton, 1939 and 1954).

60. F. FrUngel, Impulsphysik, Commercial Literature.61. H. E. Edgerton, Rev. Sci. Instr. 23, 532 (1952).62. R. P. Frazer and N. Dombrowski, HSP3, p. 376.63. H. E. Edgerton, HSP4, p. 91.64. H. E. Edgerton, J. Tredwell, and K. W. Cooper, HSP5, p.

29.65. H. Fischer, HSP5, p. 13.

66. H. Fischer, C. C. Gallagher, and P. Tandy, HSP6, p. 152.67. P. Nolan, HSP5, p. 11.

68. G. Porter and E. R. Wooding, HSP4, p. 98.69. J. S. Courtney-Pratt, HSP5, p. 197. See also J. Soc. Motion

Picture Television Engrs. 70, 509 (1961).70. J. S. Courtney-Pratt, Bell Lab. Record, 39, 142 (1961).

71. I. Hodes and H. Glenn, General Motors Defense Res. Labs.Rept. No. TR63-237 (November 1963).

72. A. T. Ellis and M. E. Fourney, Proc. IEEE 51,942, (1963).73. L. E. Hargrove, R. L. Fork, and M. A. Pollack, Appl. Phys.

Letters, 5, 4 (1964).74. Electro-Optical Instruments, Inc., Commercial Literature,

and see E. 0. Items 1, 1, 1964.75. Space Technology Labs., Commercial Literature, and see

G. L. Clark, R. F. Wuercker, and C. M. York, J. Opt. Soc.Am. 52, 878, (1962).

76. F. Friingel, W. Thorwart, and J. F. Suarez, HSP6, p. 367.77. High Speed Photography (Soc. Motion Picture Television

Engrs., New York, 1952-1957), Vols. I-VI.78. P. Naslin and J. Vivie, eds., Actes du 2e Congres International

de Photographie et Cinematographie Ultra-rapides (Dunod,Paris, 1956).


79. R. B. Collins, ed., Proc. Third International Congress on HighSpeed Photography (Butterworths, London, 1957).

80. 0. Helwich, ed., Proceedings of the Fourth InternationalCongress on High Speed Photography (Phot. Korr., Darm-stadt, 1960).

81. J. S. Courtney-Pratt, ed., Proceedings of the Fifth Inter-

national Congress on High Speed Photography (Soc. MotionPicture Television Engrs., New York, N. Y., 1962).

82. J. G. A. de Graaf and P. Tegalaar, eds., Proceedings of theSixth International Congress on High Speed Photography(Tjeenk Willink, Haarlem, 1964).

83. R. L. Aspden, Electronic Flash Photography (Macmillan,New York, 1960).

84. W. G. Hyzer, Engineering and Scientific High Speed Photo-graphy (Macmillan, New York, 1962).

85. Instrumentation and High Speed Photography, Series II (Soc.Motion Picture Television Engrs., New York, 1960-1964),Vols. 1 and 2.

86. K. R. Coleman, Rept. Progr. Phys. 26, 269 (1963).87. J. S. Courtney-Pratt, Rept. Progr. Phys., 20, 379 (1957).88. J. S. Courtney-Pratt, Phot. Korr., Special Issue No. 2

(1958).89. J. S. Courtney-Pratt, Bell Lab. Records 39, 212 (1961).

90. J. S. Courtney-Pratt, May & Baker Lab. Bull., 4, 71 (1961).91. J. S. Courtney-Pratt, Mat. Res. Std., 1, 406 (1961).

Meettngs CalendaroNovember2-13 Electronic and Optical Materials course, UCLA

Eng. Ext., U. of Calif., Los Angeles 900249-10 Symp. on Optical and Electrooptical Information

Processing Technology, Statler Hilton, Boston, Mrs.Barbara McKinney, Computer Associates, Inc., Lake-side Office Park, Wakefield, Mass.

11-13 6th Eastern Anal. Symp., Statler-Hilton Hotel,N.Y.C. Marvin Margoshes, Rm. 3, Chem. Bldg.,Nat. Bur. Stand., Wash., D.C. 20234

18 OSA Chicago Sect. Mtg., Optics in the Library byW. Lewis Hyde of U. of Rochester Anton Weigandt,1434 W. Catalpa Ave., Chicago 40

24-26 Soc. of Glass Tech., Symp. on New Methods ofChem. Anal: and the Durability of Glass, U.K.D. Hanksworth, Thornton, Hallam Gate Road,Sheffield 10, U. K.

December

3-4 R. Photog. Soc. Symp. on Optimum Results fromColor Photography, Inst. of Elect. Eng., London, C.Roberts, Res. Lab., Kodak Ltd., Harrow Middlesex,U. K.

21-23 APS, Winter Mtg. in the West, Berkeley, Calif.K. K. Darrow, Secretary, Columbia Univ., New York27, N.Y.

26-31 AAAS, 131st ann. mtg., Montreal, Canada. R. L.Taylor, AAAS, 1515 Mass. Ave. N.W., Wash. 5, D.C.

1965

January

5-7 Symp. on Glass Formation, Phase Equilibria,Nucleation, and Crystal Growth, Sheffield,D. Hawksworth, Soc. of Glass Technology,Thornton, 20 Hallam Gate Rd., Sheffield 10, U. K.

20 OSA Chicago Sect. Mtg., Plant tour of the RaulandCorp. Anton Weigandt, 1434 W. Catalpa Ave.,Chicago 40

27-30 APS, Ann. Mtg., New York City

February

17 OSA Chicago Sect. Mtg., Optical Staining by WalterMcCrone of McCrone Assoc. Anton Weigandt, 1434W. Catalpa Ave., Chicago 40

26-27 APS, K. K. Darrow, Columbia U., New York City 27

March

1-5 16th Pittsburgh Conf. on Anal. Chemistry and Appl.Spectroscopy, Pittsburgh, Pennsylvania W. G.Fateley, Mellon Inst., 4400 Forbes Ave., Pittsburgh,Pa.

20 OSA Chicago Sect. Mtg., Optical Metrology, all dayseminar at IIT Anton Weigandt, 1434 W. CatalpaAve., Chicago 40

28-Apr. 2 ASP Ann. Mtg., Amer. Cong. on Surveying andMapping, Wash., D.C.

31-Apr. 2 Optical Society of America Spring Meeting, Statler-Hilton Hotel, Dallas, Tex. M. E. Warga, OSA,1155 16th St. N.W., Wash. D.C. 20036

April- Symp. on Inhomogeneity in Glass, Sheffield D. Hawks-

worth, Soc. of Glass Technology, Thornton, 20 HallamGate Rd., Sheffield 10, U. K.

- 14th Pugwash Conf. on Science and World Affairs,Italy J. Rotblat, 8 Asmara Rd., London, N.W. 2,U. K.

21 OSA Chicago Sect. Mtg., Projection TV Systems byJohn R. Miles of John R. Miles Corp. AntonWeigandt, 1434 W. Catalpa Ave., Chicago 40

21-23 IEEE Conf. on Non-Linear Magnetics, Wash., D.C.May

5-7 1965 Microwave Theory & Techniques Symp., JackTar Harrison Hotel, Clearwater J. E. Pippin,Sperry Microwave Electronics Co., Box 1828, Clear-water, Fla.

13-14 Symp. on Signal Transmission & Processing, Colum-bia U., New York City Omar Wing, Dept. Elec.Engr., Columbia U., New York City 10027

15-21 SPSE Annual Conference, Cleveland, Ohio SPSE,P.O. Box 1609, Wash., D.C.

19 OSA Chicago Sect. Mtg., Discussion of some papersgiven at ICO, Japan, by Philip N. Slater of IITAnton Weigandt, 1434 W. Catalpa Ave., Chicago 40

23-27 IFIPS, 3rd Congress, N.Y.C. I. L. Auerbach, Auer-bach Corp., 1635 Arch St., Phila., Pa. 19103

31-June 2 5th Australian Spectroscopy Conf., Perth A. J.Parker, Dept. of Chem., U. of Western Australia,Nedlands, Australia

June- 8th Internatl. Color Mtg., Lucerne, Switzerland

Centre d'Information de la Couleur, 23, rue Notre-Dame-des-Victoires, Paris, France

- 20th Ann. Cong., Canadian Assoc. of Physicists,Vancouver, B.C.

9-11 MISFITS Conf. (Mellon Inst. Symp. on Far InfraredTranspose Spectroscopy), Pittsburgh W. G. Fateley,Mellon Institute, Pittsburgh, Pa.

14-18 Symp. Molecular Structure and Spectroscopy, OhioState U., H. H. Nielsen, Dept. Physics, OSU, 174W. 18 St., Columbus, Ohio 43210

13-18 ASTM 68th Ann. Mtg., Purdue Univ., Lafayette,Indiana

16 OSA Chicago Sect. Mtg., Activities and Responsibili-ties of Sears Color Control Lab. by N. R. Pugh ofSears Roebuck Anton Weigandt, 1434 W. CatalpaAve., Chicago 40

28-July 3 7th Internatl. Cong. on Glass, Brussels Institut Nat.du Verre, 24 rue Dourlet, Charleroi, Belgium

July12-17 12th Internatl. Spectroscopy Colloq., U. of Exeter,

England Mrs. C. E. Arregger, 1, Lowther Gardens,Prince Consort Rd., London S.W. 7

12-17 Inst. of Physics and Physical Soc. Admin. Asst.,The Institute, 47 Belgrave Sq., London, S.W. 1,England


-.... ... -� . I., ------ I . - ___ 11-_ -- .. ... 1-1---.- ........... __- ................ ......... ........ .1.111111-1--

Papers to appear in subsequent issues

Correspondence to these authors will be forwardedif addressed in care of the Managing Editor.

Design Calculations for Rotating-Mirror Cameras-IgelIR Radiometric Observations of the Solar Corona during the To-

tal Solar Eclipse of 20 July 1963-Taylor and MacQueenSpectral Reflectance and Albedo Measurements of the Earth

from High Altitudes-Band and BlockHigh Temperature Spectral Emissivities of H20-CO2 Mixtures

in the 2.71 Region-Ferriso and LudwigA Scanning Spherical Mirror Interferometer for Spectral Analysis

of Laser Radiation-Fork, Herriott, and KogelnikAn Atlas of the Absorption Spectrum of the Lower Atmosphere

from 5400-8520 X-Curcio, Drummeter, and KnestrickPrinciples of Self Modulating Derivative Optical Spectroscopy-

Bonfiglioli and BrovettoModes of Optical Maser Cavities with Roof-Top and Corner-

Cube Reflectors-BobroffTime-Resolved Photoelectric Spectrography by Electron-Optical

Image Detection of Etalon Interferograms-Bradley, Bates,Juulman, and Majumdar

A Test of Analytical Expressions for the Thermal Emissivityof Shallow Cylindrical Cavities-Kelly and Moore

A Variable Temperature Cell for Cary 14 Spectrophotometers-Koren, Brinen, and Hirt

Method of Measuring Target Temperature in a Solar Furnace-Kamada

The Caustic Curve of an Off-Axis Parabola-ScarboroughInterferometric Measurements of Rapid Phase Changes in the

Visible and Near ir Using a Laser Light Source-Buser andKainz

Comparison of Monochromatic Semiconductor Radiation Sourceswith Tungsten Lamps-Weinreich and Mayburg

Men and Milestones in Optics-III. Galileo Galilei-BarrThe Orientation of the Image Formed by a Series of Plane

Mirrors-Walles and HopkinsAn Optical Null Double Beam Far ir Spectrophotometer-

Yoshinaga, Minami, Makino, Iwahashi, Inaba, andMatsumoto

Temperature Dependence of the Solar Absorptance and ThermalEmittance of Copper, Gold, Nickel, and Silver-Thaler,Finn, Treado and Nakhleh

IR Transmittance of Optical Materials at Low Temperatures-Linsteadt

Pile-of-Plates Polarizer for the Vacuum uv-WalkerRadiant Emission Characteristics of Nonisothermal Cylindrical

Cavities-SparrowAn He-Ne Laser Amplifier-Mathias and RockAn ir Band Ratio Technique for Temperature Determination

of Hot Gases-F erriso and LudwigOptical Properties and Laser Thresholds of Thirty-nine Ruby

Laser Crystals-Dueker, Kellington, atzman, and AtwoodThe Performance of Lenses Made from Inhomogeneous Glasses-

RosberryBiaxial Electrically Switched Laser-Pole, Myers, and NuffezA Rapid-Scan ir Spectrometer; Flash Photolytic Detection of

Chloroformic Acid and of CF 2 -Herr and PimentelInternal Modulation of Optical Masers (Bandwidth Limita-

tions )-KaminowAn Automatic Continuum Compensating PhotometerforObserva-

tions of Aurora and Airglow.-F ilosofo, Greenspan, andGroom

The Reflection and Transmission of ir Materials: IV. Bibliog-raphy-McCarthy

Noise in Photoemission Current-FriedOptical Aids in Signal Processing-TuttleA New Radiation Chopper Principle-Bell and GilmerOn an Autocollimation Method of Optical Glass Heterogeneity-

BodnarA Technique for Improving Information Quality in Electron

Micrograph Prints-BonnerFrequency Spectra of He-Ne Optical Masers with External Con-

cave Mirrors-UchidaThe Four- and Five-Elements Lens Designed by Computer-

MiyamotoPerformance of Optical Detection Systems-Czerlinski and WeissSpectral Band Absorptance of Radiation Traversing Two or More

Cells in Series-PlassA Simple Grating Spectrometer for the Infrared-Bell and

GilmerRuling Engine with Hydraulic Drive-HorsfieldA Standard for Extremely Low Values of Spectral Irradiance-

Stair, Fussell, and SchneiderOn the Efficiency of Single and Multiple Elliptical Laser Cavities

-BownessReflectometer for Determining Optical Constants-PotterPhotographic Spectrometry and Radiometry on Distant Field

Sources-GuttnanA Domeless Coud6 Refractor for Solar Work-KiepenheuerThe Theory of the Absorption of Flame Radiation by Molecular

Bands-PlassCinematography of Spatial and Temporal Variations in Auroral

Forms with an Image Orthicon TV System-Hicks andDavis

A Visual Device for the Rapid Focusing and Testing of OpticalSystems-Evans

Space Velocity Coronograph-Valnicek and KleczekSpectrostratoscope (A Balloon-Borne Solar Observatory-Kiepen-

heuer and MehltretterDaytime Thermal Fluctuations in the Lower Atmosphere-WebbA New Technique for Solar Chromospheric Observations-

Larmore and RamseyThe Spectral Radiance of the Sun from 4 to 5 A-Murcray,

Murcray, and WilliamsThe Axicon-Scanned Fabry-Perot Spectrometer-KatzensteinLight Polarizer-PetersDynamic Orientation of Spin 1 Nuclei. I.-Bhatia and NarchalLaser Retinal Photocoagulator-Kapany, Silbertrust, and PeppersPockels Effect of Hexamethylenetetramine-Buhrer and HoThe Reflection and Transmission of ir Materials: III. Spectra

from 2-50 A-McCarthyDetermination of Hot Gas Temperature Profiles from ir Emission

and Absorption Spectra-Tourin and KrakowLead Selenide Detectors for Intermediate Temperature Opera-

tion-Bode, Johnson, and McLeanNote on a Letter by Kahan-VaskoOn the Possibility of using Conical Refraction Phenomena for

Laser Beam Steering-BurnsSpatial Frequency, Bandwidth, and Resolution-KellyThe Power Density Spectrum of Television Random Noise-

HuangAn Injection Laser Pump for Nd+a Doped Hosts-Harada and

SuzukiMeasurement of the Spectral Transmission of an Optical System

Employing Four Aluminized Surfaces-Wiebe and CourvilleAn Integrating Sphere System for Measuring Average Reflec-

tance and Transmittance-Davies and ZagieboyloModel for the Angular Distribution of Light Rays from a Linear

Gas Discharge Source-WenzelComment on Light Beam Deflectors-SkinnerVariable-Temperature ir Cells-Baker


Documents

High Speed Photography and Micrography