Lasers: The Light Fantastic

The sign on the gray metal door warns in red: DANGER. LASER LIGHT. Within, a smaller sign quietly continues the warning: Danger. Invisible Beams. High Energy.

There are laboratories such as this all over the country--indeed. all over the world. This one belongs to the Perkin-Elmer Corporation at Norwalk, Connecticut. It is a long, darkened room cluttered with equipment. Electrical cables lie tangled across the narrow floor space like spaghetti on a plate. The room is dominated by a single lab bench running down its middle, and on the bench is a glass pipe 30 feet long.

"This is a molecular laser," says the scientist who has been bending over the pipe, tinkering with some fixture of unguessable purpose. "It's quite new. It runs on a mix of carbon dioxide and other common gases."

He straightens up. Dr. Dane Rigden is his name: he is a British physicist who came to this country several years ago because, in his field, this is where the action is. "I'll show you how it works," he says. He turns to the 30-foot laser, then thinks of something and turns back. "By the way," he says, "keep your goggles on. And keep your hands by your sides."

He puts his own goggles on, flips some switches and turns some dials. A loud hum fills the dark room and a wave of heat comes from--where? You look at the gadgetry and frown, puzzled. The glass tube is glowing with a dim. cool, purplish light. Nothing else visible is happening.

"You've heard a lot of talk about laser death rays," says Dr. Rigden, still tinkering. "It's been mostly science fiction so far. But if there ever is such a weapon, this might be the laser used to make it." He points to one end of the long glass tube. "Coming out of there right now is a continuous thin beam of intense infrared light. You can't see it, but"--he looks to make sure your hands are down by your sides--"there's enough of it to chop your arm off."

He rummages in a grease-spotted paper bag, pulls out a thick meat bone and grips it with a pair of tongs. He holds the bone out, then lowers it into the invisible laser beam. There is a sudden blinding flash of light and a loud sput. Dr. Rigden withdraws the bone and holds its smoldering stump up for inspection. The bone has been chopped in half.

Dr. Rigden gazes at the bone stump thoughtfully. "As molecular lasers go," he says, "this one isn't unusually powerful. It delivers about two hundred and fifty watts in its beam. Raytheon and others have generated continuous beams of over 3000 watts. And last week I heard---- Well." He stops, grinning. "Security regulations, you know. Come on, I'll show you something else."

A laser lab is strangely exciting. Little knots of men stand about in the corridors, talking. Many talk with foreign accents--for, like Dr. Rigden, they have been drawn from all over the world by the promise of action. There is a profound and mysterious feeling in the air, a Christmas-morning feeling of discoveries hidden just around the corner and large events about to happen. There are no bored or weary or disappointed faces here. Everyone in the business is a perpetually surprised newcomer. The lab equipment is equally new. The complex structures of metal and glass and rubber-sheathed cable stand untidily on tables and floors. Everything has an ephemeral look, as though it were put together in an eager hurry yesterday and will be rebuilt to try out some new idea tomorrow.

"Here's something else new," says Dr. Rigden. He ducks into another dark, cluttered laboratory room and puts practiced hands on a metallic tube about two feet long. He is obviously enjoying himself. "This is an argon-gas laser. Watch."

He switches on the device. A pencil-thin beam of intense blue light shoots out and makes a tiny brilliant spot on a target at the other end of a long metal table.

"Pretty, isn't it?" says the scientist reflectively. He gazes at the target spot for a long time without moving. "You never get tired of looking at laser light."

The blue light is more than pretty. It is a blue of shining heartbreaking purity --bluer, unimaginably purer than any earthly light that shone until the 1960s. Its perfect jewellike brilliance hurts the eye, yet you can't look away. The blue target spot has a peculiar mobile quality; it seems to consist of a million tiny luminous specks that churn slowly about one another. The effect arises from the special qualities of laser light. It is hypnotic. You lean closer. . . .

"Back of a little," says Dr. Rigden. "This beam can give you a nasty burn. Here--I'll show you something else."

He tinkers with a gray box mounted next to the laser. The box clicks. Long numbers appear in windows on its face. "You're looking at a new kind of yardstick," Dr. Rigden explains. "Laser light is so pure that we know exactly what its wave length is. By knowing the wave length and by doing a little arithmetic, we can measure distances in billionths of an inch. This gadget is now measuring the distance from the laser head to the target. Here: Put your hand next to the laser."

You rest your hand on the cold metal plate on which the laser is mounted. The counting device instantly starts to click.

"Know what just happened?" asks Dr. Rigden. "The warmth of your hand expanded the metal. The distance to the target increased. Not much. Less than a hairbreadth. But enough.

You begin to understand what all the excitement is about. You begin to see why industrial companies and governments are pouring millions of dollars a year into laser research. The U. S. military services and other Government agencies have been interested in lasers from the beginning. So have the Russians. So have the British, the French and the Italians. They're fascinated by the capacity of laser light to measure distances to targets. At the moment, they're particularly fascinated by the new carbon-dioxide laser, the Buck Rogers device that generates a steady beam of enormous energy--not just a brief burst but a continuous, miles-long invisible needle. And they're fascinated by what they see in the future.

Every once in a while, from behind some imperfectly closed security curtain in Rome or London or Washington, a few tantalizing words leak out. Ron Barker, energetic young associate publisher of Laser Focus magazine, spent much of 1966 touring laser labs in Europe and the United States--and came back, he says, "with my hair standing on end. I saw things ... I heard things. . . My God, if I could only print half of it!" He can't, of course. The hints you hear nervously dropped around laser installations are not meant for publication and, in any case, the hinter always clams up when you press him for corroborating information. What he has said, in its naked form. without the necessary clothing of tangible evidence, has an apocryphal sound and can hardly be passed on without embarrassment. Billion-wait beams. Beams that can slice buildings in half or cleave steel at a distance or vaporize aircraft or mow down men as a scythe mows grass. True or false? Reality or plan or merely dream? The facts cannot be had.

The laser business is like that. You can't easily tell what's apocryphal and what isn't, for the entire science seems apocryphal. It shouldn't exist: it is improbable and outrageous. Never before in history has a scientific invention gone from mental concept to working hardware to world-wide practical application in so short a time. The raw idea of a laser was conceived only 11 years ago. The first working model was built only eight years ago. Today lasers are used in surgery, welding, drilling, surveying, weaponry. They are common items of technological hardware, available by mail order like Bunsen burners or microscopes. They are where they shouldn't really have arrived until the 21st Century. "It's like being shot into the future," says Alan Haley, regional sales manager at Perkin-Elmer. "I'm selling a product that didn't exist when I got out of college--wasn't conceived, wasn't even dreamed of. I'm selling it like ordinary hardware. I carry samples of it around. What would a career counselor have said ten or twenty years ago if I'd told him I wanted to sell ray guns for a living?"

He would have laughed, of course. The entire short, brilliant history of the laser has been one of people laughing at one another. First A laughs scornfully at B. and a few weeks later B is laughing triumphantly at A as A struggles to pry his foot from his mouth. They laughed in 1959 at the man who said he could build a laser. He did it in 1960. They laughed in 1963 when some nut at the Bell Telephone Laboratories said it was possible to make a laser spit blue light instead of red. Maybe in the 1970s, they chuckled. It happened in 1964, and now lasers produce every color of the rainbow, plus a broad range of infrared and ultraviolet. In 1961, they had developed pulsed lasers that would spit brief bursts of high-energy light, but the continuous-beam lasers were barely achieving one watt of output and everybody laughed at the idea of more. In 1968, 3000-watt steady beams have been announced and more powerful beams have carefully not been announced. In 1965, they were grinning over a statement that had become a cliche: "The laser is a solution in search of a problem." Today, salesmen are unloading lasers on hardheaded industrialists who won't buy anything unless it coldly promises a profit. Now they laugh (but in an oddly hesitant way) at other far-out ideas: death rays, building slicers, jungle (continued on page 181)Lasers(continued from page 74) mowers. Who will laugh tomorrow? At whom? About what?

Nobody cares to guess. "This crazy industry has matured when it should still be in its bottle-sucking infancy," says Bill Bushor, an engineer who founded Laser Focus three years ago and is now the industry's acknowledged chief historian. One sign of an industry's maturity is the appearance of a self-supporting technical publication covering the field, and Luser Focus lits the description. Its history has resembled that of the laser: Like one of those TV reruns that are hacked apart to make room for commercials, all the connecting scenes seem to be missing and the chronology is bewilderingly compressed. Bushor started the publication in 1965 as a mousy little newsletter, but today it blooms as a four-color job on glossy paper, fat with ads. Its offices in Newton. Massachusetts, also resemble the laser business: cluttered, untidy, expanding too last to pause and make order. "It's like being in one of those dreams where you can't stop running." says Bushor. "This is better than a two-hundred-million-dollar-a-year industry already, and some guess it could hit one billion by 1970."

So new is the science of lasers, in fact, that the inventors are still around to tell from recent memory their tales of lonely intellectual adventure--and not only still around but still young, still inventing.

The laser's history begins quietly on a park bench in Washington, D. C., and weaves a strange, obscure path through a candy store in the Bronx and other dim, unlikely places. Columbia University physicist Charles Townes is credited with starting the drama. In Washington for a scientific conference in the spring of 1951. Townes strolled early one morning into Franklin Park and sat on a bench. There, he fitted together the pieces of an idea that had been churning about in his mind. The idea was the basis of an invention that Townes later dubbed "maser" (acronym for microwave amplification by stimulated emission of radiation)--a device which, by feeding on its own internal energies, generates a powerful beam of microwaves. The invention has since proved useful in radar, spacecraft guidance and other microwave applications.

During the late 1950s. another thought began to take form in several minds simultaneously, including Townes'. Microwaves belong to a broad spectrum of electromagnetic radiation in which our world is bathed. At one end of the spectrum are radio waves, which can be anywhere from several miles in length down to about 10 centimeters--at which point microwaves begin. At the other end of the spectrum are exotic forms such as X rays, whose waves are measured in tenths of millionths of a millimeter. In between are radiations of every other conceivable wave length. To us, as humans, the most important part of this enormous spectrum is a narrow band of radiations whose wave lengths measure from roughly four to roughly seven thousandths of a milimeter. For reasons about which biologists are still arguing, the earth's major animal life forms millenniums ago developed a remarkable organ that is sensitive to this particular little group of wave lengths. This organ is the eye. The wave lengths it senses are what we call light. (The human eye and some animal eyes are so cleverly made that they can even sense minute differences in wave lengths. The longer waves give us the peculiar visual sensation that we call red: the shorter ones, violet.)

It seemed to Charles Townes and several other physicists in the late 1950s that, since light waves are the same as microwaves except for being shorter, it should be possible--theoretically--to build a device that would do with light waves what the maser did with microwaves. By 1957, there was a name for this yet-unbuilt device. It was called a laser--the "1" standing for "light"--though Townes for a long time insisted on calling it an "optical maser." But nobody had any idea how such a device might work.

Townes was beginning to get some ideas, however. So were others, and a curious dramatis personae now began to assemble. One early arrival was a man who had married Townes' sister: physicist Arthur Schawlow, then at the Bell Telephone Laboratories and now at Stanford University. Another was a research associate and doctoral student at Columbia University's Radiation Laboratory. Gordon Gould.

Gould, out of Yale in 1943, had gone to work for the Manhattan District in the Corps of Engineers, developer of the first atomic bomb. He had met a girl and one night wandered into a Marxist discussion group with her. This cost him his job and his security clearance, subsequently made it difficult for him to get into scientific laboratories. He spent the next decade struggling to get jobs and continue his physics education. He was still struggling in 1957, when some startling thoughts about lasers occurred to him.

Independently and simultaneously, similar thoughts had occurred to the brother-in-law team of Townes and Schawlow. In essence, the thoughts were that it might be possible to take some fluorescent substance and "pump" its atoms up to an excited state by hitting them with a flash of light or a jolt of electric current. Normally, these excited atoms would calm down in random fashion, emitting photons one by one and making the substance glow dimly for a few minutes. But suppose you rigged up a trap of mirrors in such a way that some of the photons began to bounce back and forth. On each bounce, the photons would hit atoms that hadn't yet calmed down. These atoms would be jolted into releasing their photons sooner than normal and the new photons would join the gathering surge and hit still more excited atoms. In this way, perhaps, you could make all the excited atoms release their photons in a billionth of a second instead of several minutes. You might produce a blast of incredibly brilliant light. If you provided a way for some of the light to escape the mirror trap--maybe by making one mirror only partially reflective--you might get a beautiful strong beam.

In trying to explain these thoughts, Townes would sometimes ask puzzled listeners to think of a long swimming pool. At one end, rising from the water, you elect a thin wobbly pole, and atop the pole you build a platform. You hoist rocks onto the platform. This is analogous to the pumping up of atoms to their excited state. If the rocks release their stored energy (that is, fall into the pool) in random fashion, the result will be only a pool of choppy water. But suppose you rig the system to feed on its own energies in an orderly way. You let just one rock fall in. A nice tidy wave travels to the other end of the pool and bounces back. It jiggles the pole and this makes another rock fall in. This second rock hits the water at just the right time to amplify the existing wave. In other words, its energies fall into step much like photons in a laser. The bigger wave travels down the pool and back, the pole wobbles, a third rock falls in and the wave grows still bigger. And so on.

Dr. Townes referred to this concept as "wave amplification by stimulated emission of rocks"--that is, a waser.

Gordon Gould, contemplatively commuting from Columbia University to a Bronx apartment, believed he had this field of thought to himself. But one night just before Halloween in 1957. Townes phoned him. The two had met occasionally on Columbia's campus. Townes wanted some data about certain high-intensity lamps with which Gould was working at the Radiation Lab. Townes' questions made Gould suddenly ask a question of his own: "Is Townes thinking what I'm thinking?"

Gould plunged into an undeclared race against Townes. He worked night and day on his laser calculations. One cold November night. Gould and his wife left their apartment and walked a few blocks to a candy store whose proprietor doubled as a notary public. Clutched in Gould's hand was a dirty gray laboratory notebook bearing the title "Some Rough Calculations on the Feasibility of a Laser." The notary witnessed it and dated it: Friday, the 13th of November, 1957.

Townes and Schawlow were making their own rough calculations about the same time. By mid-1958, they felt their figuring was specific enough to be patentable, and they and the Bell Labs applied for the law's protection. Gould, working alone with little equipment and a small budget, hampered by security restrictions, was farther behind. Seeking help, he left his university job and took his notes to a small scientific outfit named TRG. now an affluent laser-making division of Control Data Corporation. Intrigued. TRG took him in and put him in a lab where no security clearance was required. He and TRG applied for their patent in early 1959.

A series of court battles then began. Some experts later said Townes and Schawlow's papers most nearly described the laser as it eventually came to be: some said Gould's, Gould's notarized notebook bore the earliest date, and it was mostly on this basis that Gould claimed to have conceived the invention first. But the court turned him down, largely because he hadn't proved "diligence" in going from general concept to specific calculations and thence toward hardware. The Bell Labs team was awarded a patent with the fetchingly rhythmic number 2,929,922.

Meanwhile, another interesting character had drifted on stage. This was Ted Maiman of Hughes Research Laboratories, who claims that he, too, deserves credit for inventing the laser.

In 1959 and early 1960, though the patent battle was already joined, nobody had actually made a laser. Dozens of large corporations were trying: the Bell Labs. Westinghouse. General Electric. Raytheon. Many were trying it with potassium vapor and related gases, which seemed theoretically to promise the best results. They had great expensive, science-fictionish rigs on their lab tables. Every now and then, something would explode or an overloaded circuit would disintegrate and the scientists would curse and build a new, even less probable-looking contraption. And what of Ted Maiman?

It was laughable. Compared with the giant corporations that were thundering up and down the laser trail. Maiman was a mouse rustling in the weeds. He had a small, cramped, cluttered lab room at Hughes' Malibu Research Laboratories in California. Hughes supported him because he was considered a bright young fellow: but the hope was that he could eventually turn to something more promising. Maiman was pursuing a magnificently ridiculous notion. He was trying to make a laser out of a ruby.

A ruby? There were several impressive reasons you couldn't make a laser out of a ruby. Ruby had been shown to lack the required quantum efficiency--in lay terms, the go. Moreover, it obviously wouldn't be able to take the heat without cracking. Yet Maiman chose to ignore these facts. He had a ruby crystal about the size and shape of a pencil stub. Its ends were ground parallel and were silvered, one more completely than the other. This was the heart of his proposed laser. The rest was like something from a five-and-dime store. Curled around the ruby was an ordinary helical flash tube, the kind photographers use. This was intended to provide the "pumping" light that would excite the ruby's atoms. Wrapped around the flash helix, in turn, was a dented aluminum reflector. That was all.

"Forget it, we've tried it, it won't work," some visiting Bell Labs physicists had assured Maiman. He had to admit the gadget didn't work yet, but he refused to admit it wouldn't. He was becoming the comic relief of the laser quest. He'd submitted a paper on his proposed laser to a technical journal, but the editor had rejected it. A photographer had come around to take a picture of the nonworking laser but had found it so unimpressive ("Like something a plumber might have screwed together," he said) that he asked Maiman to build a bigger, more scientific-looking mock-up. Another company had copied the picture to make its own ruby laser, and of course this laser didn't work, and this only increased Maiman's embarrassment.

"I'm sure it's just on the threshold of working," he said one day in June 1960 to a group of East Coast scientists. They'd come West for a convention and were indulging in the great new California sport of Dropping In On Maiman. They nodded politely as Maiman carnestly explained his reasoning. They left, nudging each other in the ribs. Maiman chomped his cigar gloomily.

Shortly afterward, his lab assistant, a matt named Irnee D'Haenens, came in with a package. It contained three new ruby crystals of improved optical character, fabricated and polished with special loving care by the Linde Company, expert crystal maker. Maiman and D'Haenens mounted one of the new crystals in the gadget. They looked at each other. D'Haeneus quietly closed the lab door. Maiman threw a switch and the helix flashed.

And a tiny spot of brilliant red light appeared momentarily on the laboratory wall.

Bob Meyer, a Hughes publicity man, recalls being summoned to the Malibu lab building the next day. "The place was buzzing with excitement. People were standing around in the corridors babbling at each other. I couldn't understand what it was all about. I'd heard the word 'laser,' but I didn't really know what it was supposed to be."

The lab director, Dr. Lester Van Atta, tried to explain. "Great news!" he shouted at Meyer. "Maiman has achieved laser action!"

That was eight short years ago. Today, almost every newspaper-reading man in every industrial nation knows what a laser is. Literally thousands of lasers exist and literally hundreds of scientific groups throughout the world are working on improvements. "I knew I had something important," says Maiman, "but I never dreamed of anything like this."

The ruby laser today is the most powerful, though not in all respects the most useful, in the business. "We've developed continuous-wave ruby lasers, but most still operate in short pulses." says physicist Dr. Richard Daly of TRG. the outfit that took in the struggling Gordon Gould in his hour of need. "Pulsed operation isn't always what you want in every application. But it's right for many uses. Here--let me show you."

Daly has the typical laser man's foundness for showing off his gadgetry. In a large, windowless lab room, Daly tinkers with a thick metallic tube. He turns some dials. You adjust your goggles. He flips a switch and there is a sharp crack like a rifle shot. At the other end of the lab, a metal target seems to explode with a blinding white flash and a huge sunburst of sparks.

The metal is steel. In its center is a smoking hole about half an inch deep.

"This is a giant-pulse ruby laser." explains Daly. "You didn't actually see the laser light, because it was such a short pulse. It was a slug of light not much longer than your outstretched arms. But there was a lot of oomph in it. About a gigawatt."

A gigawatt is a billion watts. You can nearly go blind just thinking about that much light in that small a space. For comparison, consider the sun. On a clear summer day at high noon, the sun pours energy onto your head at a density of about one tenth of a watt per square centimeter. This much light can blind you if you look directly into it for long. But even an unfocused laser beam can deliver energy at literally millions of times that density. "Focused carefully." says Dr. R. D. Haun of Westinghouse, "a laser beam can deliver ten billion watts to a square centimeter."

It isn't not only the power of laser beams that fascinates scientists. It's also the quality of utter neatness. A laser beam is "coherent"--meaning, in effect, orderly, like a good TV broadcast beam. Ordinary light is untidy. Its waves are of diverse sizes and never quite lined up right, and each photon behaves in a slightly different way as it passes through a focusing lens. Even the best lens can't focus this untidy light to a point, only to a fuzzy-edged blob. But laser light has been focused to a spot as small as 1/10,000 inch.

Jobs both of brute force and of microscopic tenderness can be done with light like this. TRG, for instance, sells a microscope-mounted laser that can deliver a pinprick of energy delicate enough to burn a single chromosome inside a living cell--a capability now being used in studies of genetics. An equally delicate Westinghouse laser recently drilled three neat round holes in a row across the breadth of a human hair.

Slightly more powerful beams are used in surgery. The American Optical Company, for example, makes a special laser instrument for operations inside the eye. By passing the beam through the eye's transparent cornea and lens, doctors can burn away a blood clot or weld a detached retina inside the eye without touching the outer parts. At the Children's Hospital of Cincinnati, doctors are experimenting with lasers in destroying cancers, drilling teeth and removing warts, tattoos and birthmarks--and, at the same time, they are trying to find exactly what laser light does to human skin and other tissues. Director of the laser laboratory Dr. Leon Goldman, who has deliberately pricked himself with laser beams some 450 times, remarks that physicians as a group are often a decade late in taking advantage of scientific developments. But they began working with the laser almost as soon as it was invented.

Industrial engineers have also been quick to use the laser. Take the enormously varied, omnipresent industrial problem of hole drilling. "A laser beam can vaporize any substance on earth." says Ted Maiman. "That's why all kinds of engineers, drilling holes in all kinds of materials, have fallen in love with the laser." The Wurlitzer Company, for example, maker of pianos and other large musical instruments, for years has worn out bits by the hundreds drilling some 80,000 holes a day in hard rock maple to a tolerance of 1/2000 inch. "Please say it can be done with a laser!" a Wurlitzer engineer begged TRG: and TRG. not having the heart to turn him away, is now designing a light-beam tool for the purpose. It shouldn't prove difficult, for a laser beam can even punch a hole through a diamond. Many types of fine wire are made by drawing soft metal through minuscule holes drilled in diamonds: and in the past, it used to take two to three days to drill such a hole. A laser tool made by Western Electric does it in a few minutes.

The U. S. Department of Commerce and MIT are now dreaming about much larger holes. Late in 1966, two MIT sophomores, ignoring the amused chuckling of their professors, borrowed a powerful carbon-dioxide laser from Raytheon and trained its beam on a chunk of granite for 30 seconds. When they picked the granite up, it crumbled like dry mud. Engineering professor Robert Williams now believes this startling effect may be a key to fast, cheap tunneling. It may be possible to build a laser-headed boring machine that can cat its way through rock like a worm through cheese. The Commerce Department, interested in rapid-transit tunnels between cities, has encouraged MIT to probe further.

Because laser light is orderly, it can also be used for communication. Its waves can be modulated exactly like radio waves or microwaves--and this is another application that brings a gleam to the eyes of scientists. The National Aeronautics and Space Administration has hired several companies to wonder about sending messages through interplanetary space on a laser beam. "A radio or radar beam fans out widely," says a Perkin-Elmer scientist who is working on this idea, "and after traveling millions of miles to get here from Mars, for example, its energy would be so far dissipated that we'd barely be able to pick it up. But a laser beam can be made so tight. so narrow, that it can get here from Mars and still be going strong." The U. S. Army is also interested in the laser as an instrument of battlefield communication. Radio messages fan out and can easily be picked up by an enemy. But a message sent on a laser beam would go nowhere but to a single receiver--and even if the enemy saw the beam and tried to read it. he'd give himself away the instant he poked his receiving device into it.

The tidiness of laser light has also made possible a photographic technique called holography. A hologram is, in effect, a true three-dimensional image of an object. Instead of showing only some of the object's surfaces, as an ordinary photograph does, a hologram shows all surfaces--faithfully re-creates the entire object in light. By turning the hologram or walking around it, you can see the back of the object. This spooky effect depends on complex phenomena of diffraction and can be obtained only by illuminating the object with the coherent light of a laser. Industrial companies have begun using holograms to study, among other things, stresses in metals. Engineers might make a hologram of an aircraft-wing part, for example, while the part is at rest, then make another stop-action hologram while the part is vibrating as in flight. By comparing the two images, they see precisely how and in what dimensions the part was strained out of shape.

Bob Whitman, an artist with an ability to sell far-out ideas to large organizations, has discovered yet another use for the laser's eerie light. Working with Bell Labs engineers. Whitman this year built what he called "light drawings" at the Pace Gallery in New York. These might be compared with line drawings on paper, except that the lines are thin, colored, low-powered laser beams and the viewer stands within the three-dimensional drawing and "experiences" it instead of merely contemplating it from without. Whitman calls the drawings "articulations of space." Bell Labs people, who cooperated for reasons of publicity, are not quite sure what to call the drawings. Asked to comment, a company spokes-man explained: "Well, this laser art is--it kind of--um. Well, we enjoyed working with Bob Whitman."

But of all the actual, possible and imaginable uses of the laser, the one that generates the most excitement is that of weaponry. The U. S. Army and Navy are known to be working strenuously on destructive light beams, but have kept the effort secret. The Air Force was less successful at first in keeping its lip zipped. General Curtis LeMay's speeches used to contain cryptic comments about "beam-directed energy weapons": but in the past few years, the Air Force has declined to comment further on the subject. Similar secrecy shrouds laser research in Europe (and, of course, in Russia), though national pride occasionally forces security curtains to be lifted briefly. Late in 1966. Britain's Services Electronics Research Laboratory, a government science center, showed off some of its laser developments, and one item on display was a portable, battery-powered laser rifle. The cool-voiced British scientists referred to it smilingly as "a toy, of course." and showed how it could be used to pop balloons. Yet it is hard to believe that the frugal British government would spend its taxpayers' money to build balloon poppers for the lunch-hour entertainment of scientists. Such a rifle could be used in combat to blind enemy troops--and, at higher power, to do the same kinds of damage bullets do. or worse.

The new family of molecular lasers--particularly carbon-dioxide lasers--interests military men, because they offer high power as well as continuous-beam operation. Such lasers work, in effect, by setting up a sort of vibration within molecules instead of dealing with excited atoms. Theoretically, they are capable of enormously higher power than anything yet developed. Raytheon. Westinghouse, Perkin-Elmer and dozens of other companies have military contracts to study molecular lasers--contracts surrounded with elaborate secrecy. One of Perkin-Elmer's contracts has required the company to build an odd-shaped tall room: and although any visitor may peek into the room (after proving that he's a U. S. citizen), most of the company's employees and executives are mystified about the room's uses.

"If you think the laser business has produced surprises over the past few years, wait until the next few." says Gordon Gould. Like the laser. Gould since 1960 has risen rapidly from nowhere to prominence. Though he lost his fight for the basic laser patent, he now holds several other important patents in the field and has applied for others. These and a Control Data (including TRG) stock option have made him suddenly quite wealthy. Among his new possessions is a boat in which he periodically sails in the West Indies, gazes across vast ocean reaches and tries to see the future.

What he can see looks good to him. He left TRG in 1966 to become a professor at the Polytechnic Institute of Brooklyn. His basic job there is not to teach but to research and invent. He is interested in a new copper-vapor laser that produces green light of potentially colossal brightness. He is interested in picosecond pulses (a picosecond is a millionth of a millionth of a second). He is interested in more things than can conveniently be cataloged.

"It seems strange to say this when lasers are in such wide use," says Professor Gould, "but the laser is still a very young invention. It has only just begun. The possibilities ahead are--well, it's a word scientists don't like to use, but what else can I say? Fantastic."