Today we will talk about how to make a powerful green or blue laser yourself at home from scrap materials with your own hands. We will also consider drawings, diagrams and the design of homemade laser pointers with an igniting beam and a range of up to 20 km

The basis of the laser device is an optical quantum generator, which, using electrical, thermal, chemical or other energy, produces a laser beam.

The operation of a laser is based on the phenomenon of forced (induced) radiation. Laser radiation can be continuous, with constant power, or pulsed, reaching extremely high peak powers. The essence of the phenomenon is that an excited atom is capable of emitting a photon under the influence of another photon without its absorption, if the energy of the latter is equal to the difference in the energies of the levels of the atom before and after the radiation. In this case, the emitted photon is coherent with the photon that caused the radiation, that is, it is its exact copy. This way the light is amplified. This phenomenon differs from spontaneous radiation, in which the emitted photons have random propagation directions, polarization and phase
The probability that a random photon will cause stimulated emission from an excited atom is exactly equal to the probability of absorption of this photon by an atom in an unexcited state. Therefore, to amplify light, it is necessary that there be more excited atoms in the medium than unexcited ones. In a state of equilibrium, this condition is not satisfied, so various systems for pumping the laser active medium are used (optical, electrical, chemical, etc.). In some schemes, the laser working element is used as an optical amplifier for radiation from another source.

There is no external flow of photons in a quantum generator; an inverse population is created inside it using various pump sources. Depending on the sources there are various ways pumping:
optical - powerful flash lamp;
gas discharge in the working substance (active medium);
injection (transfer) of current carriers in a semiconductor in the zone
p-n transitions;
electronic excitation (irradiation of a pure semiconductor in a vacuum with a flow of electrons);
thermal (heating of gas followed by rapid cooling;
chemical (using the energy of chemical reactions) and some others.

The primary source of generation is the process of spontaneous emission, therefore, to ensure the continuity of generations of photons, the existence of a positive feedback is necessary, due to which the emitted photons cause subsequent acts of induced emission. To do this, the laser active medium is placed in an optical cavity. In the simplest case, it consists of two mirrors, one of which is translucent - through it the laser beam partially exits the resonator.

Reflecting from the mirrors, the radiation beam passes repeatedly through the resonator, causing induced transitions in it. The radiation can be either continuous or pulsed. At the same time, using various devices to quickly turn the feedback off and on and thereby reduce the period of the pulses, it is possible to create conditions for generating radiation of very high power - these are the so-called giant pulses. This mode of laser operation is called Q-switched mode.
The laser beam is a coherent, monochrome, polarized, narrowly directed light flux. In a word, this is a beam of light emitted not only by synchronous sources, but also in a very narrow range, and directionally. A sort of extremely concentrated light flux.

The radiation generated by a laser is monochromatic, the probability of emission of a photon of a certain wavelength is greater than that of a closely located one, associated with the broadening of the spectral line, and the probability of induced transitions at this frequency also has a maximum. Therefore, gradually during the generation process, photons of a given wavelength will dominate over all other photons. In addition, due to the special arrangement of the mirrors, only those photons that propagate in a direction parallel to the optical axis of the resonator at a short distance from it are retained in the laser beam; the remaining photons quickly leave the resonator volume. Thus, the laser beam has a very small divergence angle. Finally, the laser beam has a strictly defined polarization. To do this, various polarizers are introduced into the resonator; for example, they can be flat glass plates installed at a Brewster angle to the direction of propagation of the laser beam.

The working wavelength of the laser, as well as other properties, depend on what working fluid is used in the laser. The working fluid is “pumped” with energy to produce an inversion effect of electronic populations, which causes stimulated emission of photons and an optical amplification effect. The simplest form of an optical resonator is two parallel mirrors (there can also be four or more) located around the laser working fluid. The stimulated radiation of the working fluid is reflected back by the mirrors and is again amplified. Until the moment it comes out, the wave can be reflected many times.

So, let us briefly formulate the conditions necessary to create a source of coherent light:

you need a working substance with inverted population. Only then can light amplification be achieved through forced transitions;
the working substance should be placed between the mirrors that provide feedback;
the gain given by the working substance, which means the number of excited atoms or molecules in the working substance must be greater than a threshold value depending on the reflection coefficient of the output mirror.

The following types of working fluids can be used in the design of lasers:

Liquid. It is used as a working fluid, for example, in dye lasers. The composition includes an organic solvent (methanol, ethanol or ethylene glycol) in which chemical dyes (coumarin or rhodamine) are dissolved. Working length The wavelength of liquid lasers is determined by the configuration of the dye molecules used.

Gases. In particular, carbon dioxide, argon, krypton or gas mixtures, as in helium-neon lasers. “Pumping” with the energy of these lasers is most often carried out using electrical discharges.
Solids (crystals and glasses). The solid material of such working fluids is activated (doped) by adding a small amount of chromium, neodymium, erbium or titanium ions. Common crystals used are yttrium aluminum garnet, lithium yttrium fluoride, sapphire (aluminum oxide), and silicate glass. Solid-state lasers are usually "pumped" by a flash lamp or other laser.

Semiconductors. A material in which the transition of electrons between energy levels can be accompanied by radiation. Semiconductor lasers are very compact and “pumpable” electric shock, allowing them to be used in consumer devices such as CD players.

To turn an amplifier into an oscillator, it is necessary to organize feedback. In lasers, this is achieved by placing the active substance between reflecting surfaces (mirrors), forming a so-called “open resonator” due to the fact that part of the energy emitted by the active substance is reflected from the mirrors and again returns to the active substance

The Laser uses optical resonators of various types - with flat mirrors, spherical, combinations of flat and spherical, etc. In optical resonators that provide feedback in the Laser, only certain types of oscillations of the electromagnetic field can be excited, which are called natural oscillations or modes of the resonator.

Modes are characterized by frequency and shape, i.e., the spatial distribution of vibrations. In a resonator with flat mirrors, the types of oscillations corresponding to plane waves propagating along the axis of the resonator are predominantly excited. A system of two parallel mirrors resonates only at certain frequencies - and in the laser also plays the role that an oscillatory circuit plays in conventional low-frequency generators.

The use of an open resonator (and not a closed one - a closed metal cavity - characteristic of the microwave range) is fundamental, since in the optical range a resonator with dimensions L = ? (L is the characteristic size of the resonator, ? is the wavelength) simply cannot be manufactured, and at L >> ? a closed resonator loses its resonant properties because the number of possible types of oscillations becomes so large that they overlap.

The absence of side walls significantly reduces the number of possible types of oscillations (modes) due to the fact that waves propagating at an angle to the axis of the resonator quickly go beyond its limits, and allows maintaining the resonant properties of the resonator at L >> ?. However, the resonator in the laser not only provides feedback due to the return of radiation reflected from the mirrors into the active substance, but also determines the spectrum of the laser radiation, its energy characteristics, radiation direction.
In the simplest approximation of a plane wave, the condition for resonance in a resonator with flat mirrors is that an integer number of half-waves fits along the length of the resonator: L=q(?/2) (q is an integer), which leads to an expression for the frequency of the oscillation type with the index q: ?q=q(C/2L). As a result, the radiation spectrum of light, as a rule, is a set of narrow spectral lines, the intervals between which are identical and equal to c/2L. The number of lines (components) for a given length L depends on the properties of the active medium, i.e., on the spectrum of spontaneous emission at the quantum transition used and can reach several tens and hundreds. Under certain conditions, it turns out to be possible to isolate one spectral component, i.e., to implement a single-mode lasing mode. The spectral width of each component is determined by the energy losses in the resonator and, first of all, by the transmission and absorption of light by the mirrors.

The frequency profile of the gain in the working substance (it is determined by the width and shape of the line of the working substance) and the set of natural frequencies of the open resonator. For open resonators with a high quality factor used in lasers, the resonator passband ??p, which determines the width of the resonance curves of individual modes, and even the distance between neighboring modes ??h turn out to be less than the gain linewidth ??h, and even in gas lasers, where the line broadening is the smallest. Therefore, several types of resonator oscillations enter the amplification circuit.

Thus, the laser does not necessarily generate at one frequency; more often, on the contrary, generation occurs simultaneously at several types of oscillations, for which the amplification? more losses in the resonator. In order for the laser to operate at one frequency (in single-frequency mode), it is necessary, as a rule, to take special measures (for example, increase losses, as shown in Figure 3) or change the distance between the mirrors so that only one gets into the gain circuit. fashion. Since in optics, as noted above, ?h > ?p and the generation frequency in a laser is determined mainly by the resonator frequency, then in order to keep the generation frequency stable, it is necessary to stabilize the resonator. So, if the gain in the working substance covers the losses in the resonator for certain types of oscillations, generation occurs on them. The seed for its occurrence is, as in any generator, noise, which represents spontaneous emission in lasers.
In order for the active medium to emit coherent monochromatic light, it is necessary to introduce feedback, i.e., part of what is emitted by this medium luminous flux send back into the medium to produce stimulated emission. Positive Feedback is carried out using optical resonators, which in the elementary version are two coaxially (parallel and along the same axis) mirrors, one of which is translucent, and the other is “deaf,” i.e., completely reflects the light flux. The working substance (active medium), in which an inverse population is created, is placed between the mirrors. Stimulated radiation passes through the active medium, is amplified, reflected from the mirror, passes through the medium again and is further amplified. Through a translucent mirror, part of the radiation is emitted into the external environment, and part is reflected back into the environment and amplified again. Under certain conditions, the flux of photons inside the working substance will begin to increase like an avalanche, and the generation of monochromatic coherent light will begin.

The principle of operation of an optical resonator, the predominant number of particles of the working substance, represented by open circles, are in the ground state, i.e., at the lower energy level. Just not a large number of particles, represented by dark circles, are in an electronically excited state. When the working substance is exposed to a pumping source, the majority of particles go into an excited state (the number of dark circles has increased), and an inverse population is created. Next (Fig. 2c) spontaneous emission of some particles occurring in an electronically excited state occurs. Radiation directed at an angle to the axis of the resonator will leave the working substance and the resonator. Radiation, which is directed along the axis of the resonator, will approach the mirror surface.

For a translucent mirror, part of the radiation will pass through it into environment, and part of it will be reflected and again directed into the working substance, involving particles in an excited state in the process of stimulated emission.

At the “deaf” mirror, the entire radiation flux will be reflected and again pass through the working substance, inducing radiation from all remaining excited particles, which reflects the situation when all the excited particles gave up their stored energy, and at the output of the resonator, on the side of the translucent mirror, a powerful flux of induced radiation was formed.

The main structural elements of lasers include a working substance with certain energy levels of their constituent atoms and molecules, a pump source that creates population inversion in the working substance, and an optical cavity. There are a large number of different lasers, but they all have the same and simple schematic diagram device, which is shown in Fig. 3.

The exception is semiconductor lasers due to their specificity, since everything about them is special: the physics of the processes, pumping methods, and design. Semiconductors are crystalline formations. In an individual atom, the electron energy takes on strictly defined discrete values, and therefore the energy states of the electron in the atom are described in the language of levels. In a semiconductor crystal, energy levels form energy bands. In a pure semiconductor that does not contain any impurities, there are two bands: the so-called valence band and the conduction band located above it (on the energy scale).

Between them there is a gap of forbidden energy values, which is called the bandgap. At a semiconductor temperature equal to absolute zero, the valence band should be completely filled with electrons, and the conduction band should be empty. In real conditions, the temperature is always above absolute zero. But an increase in temperature leads to thermal excitation of electrons, some of them jump from the valence band to the conduction band.

As a result of this process, a certain (relatively small) number of electrons appears in the conduction band, and a corresponding number of electrons will be missing in the valence band until it is completely filled. An electron vacancy in the valence band is represented by a positively charged particle, which is called a hole. The quantum transition of an electron through the band gap from bottom to top is considered as a process of generating an electron-hole pair, with electrons concentrated at the lower edge of the conduction band, and holes at the upper edge of the valence band. Transitions through the forbidden zone are possible not only from bottom to top, but also from top to bottom. This process is called electron-hole recombination.

When a pure semiconductor is irradiated with light whose photon energy slightly exceeds the band gap, three types of interaction of light with matter can occur in the semiconductor crystal: absorption, spontaneous emission and stimulated emission of light. The first type of interaction is possible when a photon is absorbed by an electron located near the upper edge of the valence band. In this case, the energy power of the electron will become sufficient to overcome the band gap, and it will make a quantum transition to the conduction band. Spontaneous emission of light is possible when an electron spontaneously returns from the conduction band to the valence band with the emission of an energy quantum - a photon. External radiation can initiate the transition to the valence band of an electron located near the lower edge of the conduction band. The result of this third type of interaction of light with the semiconductor substance will be the birth of a secondary photon, identical in its parameters and direction of movement to the photon that initiated the transition.

To generate laser radiation, it is necessary to create an inverse population of “working levels” in the semiconductor—to create a sufficiently high concentration of electrons at the lower edge of the conduction band and a correspondingly high concentration of holes at the edge of the valence band. For these purposes, pure semiconductor lasers are usually pumped by an electron flow.

The resonator mirrors are polished edges of the semiconductor crystal. The disadvantage of such lasers is that many semiconductor materials generate laser radiation only at very low temperatures, and the bombardment of semiconductor crystals by a stream of electrons causes it to become very hot. This requires additional cooling devices, which complicates the design of the device and increases its dimensions.

The properties of semiconductors with impurities differ significantly from the properties of unimpurity, pure semiconductors. This is due to the fact that atoms of some impurities easily donate one of their electrons to the conduction band. These impurities are called donor impurities, and a semiconductor with such impurities is called an n-semiconductor. Atoms of other impurities, on the contrary, capture one electron from the valence band, and such impurities are acceptor, and a semiconductor with such impurities is a p-semiconductor. The energy level of impurity atoms is located inside the band gap: for n-semiconductors - near the lower edge of the conduction band, for /-semiconductors - near the upper edge of the valence band.

If in this area you create electrical voltage so that on the side of the p-semiconductor there is a positive pole, and on the side of the n-semiconductor there is a negative one, then under the influence of an electric field electrons from the n-semiconductor and holes from the /^-semiconductor will move (injected) into area p-n— transition.

When electrons and holes recombine, photons will be emitted, and in the presence of an optical resonator, laser radiation can be generated.

The mirrors of the optical resonator are polished edges of the semiconductor crystal, oriented perpendicularly p-n plane— transition. Such lasers are miniature, since the size of the semiconductor active element can be about 1 mm.

Depending on the characteristic under consideration, all lasers are divided as follows).

First sign. It is customary to distinguish between laser amplifiers and generators. In amplifiers, weak laser radiation is supplied at the input, and it is correspondingly amplified at the output. There is no external radiation in the generators; it arises in the working substance due to its excitation using various pump sources. All medical laser devices are generators.

The second sign is the physical state of the working substance. In accordance with this, lasers are divided into solid-state (ruby, sapphire, etc.), gas (helium-neon, helium-cadmium, argon, carbon dioxide, etc.), liquid (liquid dielectric with impurity working atoms of rare earth metals) and semiconductor (arsenide -gallium, gallium arsenide phosphide, lead selenide, etc.).

The method of exciting the working substance is the third distinctive feature of lasers. Depending on the excitation source, lasers are distinguished: optically pumped, pumped by a gas discharge, electronic excitation, injection of charge carriers, thermally pumped, chemically pumped, and some others.

The laser emission spectrum is the next classification feature. If the radiation is concentrated in a narrow range of wavelengths, then the laser is considered monochromatic and its technical data indicates a specific wavelength; if in a wide range, then the laser should be considered broadband and the wavelength range is indicated.

Based on the nature of the emitted energy, pulsed lasers and lasers with continuous radiation are distinguished. The concepts of a pulsed laser and a laser with frequency modulation of continuous radiation should not be confused, since in the second case we essentially receive intermittent radiation of various frequencies. Pulsed lasers have high power in a single pulse, reaching 10 W, while their average pulse power, determined by the corresponding formulas, is relatively small. For continuous frequency modulated lasers, the power in the so-called pulse is lower than the power of continuous radiation.

Based on the average radiation output power (the next classification feature), lasers are divided into:

· high-energy (the generated radiation power flux density on the surface of an object or biological object is over 10 W/cm2);

· medium-energy (generated radiation power flux density - from 0.4 to 10 W/cm2);

· low-energy (the generated radiation power flux density is less than 0.4 W/cm2).

· soft (generated energy irradiation - E or power flux density on the irradiated surface - up to 4 mW/cm2);

· average (E - from 4 to 30 mW/cm2);

· hard (E - more than 30 mW/cm2).

In accordance with " Sanitary standards and rules for the design and operation of lasers No. 5804-91”, according to the degree of danger of the generated radiation for operating personnel, lasers are divided into four classes.

First class lasers include: technical devices, the output collimated (enclosed in a limited solid angle) radiation of which does not pose a danger when irradiating human eyes and skin.

Second class lasers are devices whose output radiation poses a danger when irradiating the eyes with direct and specularly reflected radiation.

Lasers of the third class are devices whose output radiation poses a danger when irradiating the eyes with direct and specularly reflected, as well as diffusely reflected radiation at a distance of 10 cm from a diffusely reflective surface, and (or) when irradiating the skin with direct and specularly reflected radiation.

Class 4 lasers are devices whose output radiation poses a hazard when the skin is irradiated with diffusely reflected radiation at a distance of 10 cm from a diffusely reflective surface.

Each of us held a laser pointer in our hands. Despite the decorative use, it contains a real laser, assembled on the basis of a semiconductor diode. The same elements are installed on laser levels and.

The next popular product assembled on a semiconductor is your computer's DVD burner drive. It contains a more powerful laser diode with thermal destructive power.

This allows you to burn a layer of the disc, depositing tracks with digital information on it.

How does a semiconductor laser work?

Devices of this type are inexpensive to produce and the design is quite widespread. The principle of laser (semiconductor) diodes is based on the use classic p-n transition. This transition works the same as in conventional LEDs.

The difference is in the organization of radiation: LEDs emit “spontaneously”, while laser diodes emit “forced”.

The general principle of the formation of the so-called “population” of quantum radiation is fulfilled without mirrors. The edges of the crystal are mechanically chipped, providing a refractive effect at the ends, akin to a mirror surface.

For getting various types radiation, a “homojunction” can be used, when both semiconductors are the same, or a “heterojunction”, with different materials transition.


The laser diode itself is an accessible radio component. You can buy it in stores that sell radio components, or you can extract it from an old one. DVD-R drive(DVD-RW).

Important! Even the simple laser used in light pointers can cause serious damage to the retina of the eye.

More powerful installations, with a burning beam, can deprive vision or cause burns to the skin. Therefore, use extreme caution when working with such devices.

With such a diode at your disposal, you can easily make a powerful laser with your own hands. In fact, the product may be completely free, or it will cost you a ridiculous amount of money.

DIY laser from a DVD drive

First, you need to get the drive itself. It can be removed from an old computer or purchased at a flea market for a nominal cost.

Many radio amateurs have wanted to make a laser with their own hands at least once in their lives. It was once believed that it could only be collected in scientific laboratories. Yes, this is true if we talk about huge laser installations. However, you can assemble a simpler laser, which will also be quite powerful. The idea seems very complicated, but in reality it is not difficult at all. In our article with video we will talk about how you can assemble your own laser at home.

DIY powerful laser

DIY laser circuit

It is very important to follow basic safety rules. Firstly, when checking the operation of the device or when it is already fully assembled, under no circumstances should you point it at the eyes, other people or animals. Your laser will be so powerful that it can light a match or even a sheet of paper. Secondly, follow our scheme and then your device will work for a long time and with high quality. Thirdly, do not let children play with it. Finally, store the assembled device in a safe place.

To assemble a laser at home, you will not need too much time and components. So, first you need a DVD-RW drive. It can be either working or non-working. This is not important. But it is very important that it is a recording device, and not a regular drive for playing discs. The drive's write speed should be 16x. It can be higher. Next, you will need to find a module with a lens, thanks to which the laser can focus at one point. An old Chinese pointer may well be suitable for this. It is best to use an unnecessary steel flashlight as the body of the future laser. The “filling” for it will be wires, batteries, resistors and capacitors. Also, do not forget to prepare a soldering iron - without it, assembly will be impossible. Now let's see how to assemble a laser from the components described above.

DIY laser circuit

The first thing you need to do is disassemble the DVD drive. You need to remove the optical part from the drive by disconnecting the cable. Then you will see a laser diode - it should be carefully removed from the housing. Remember that the laser diode is extremely sensitive to temperature changes, especially cold. Until you install a diode in the future laser, it is best to rewind the diode leads with thin wire.

Most often, laser diodes have three terminals. The one in the middle gives a minus. And one of the extreme ones is a plus. You should take two AA batteries and connect them to the diode removed from the case using a 5 Ohm resistor. In order for the laser to light up, you need to connect the negative battery to the middle terminal of the diode, and the positive one to one of the outer terminals. Now you can assemble the laser emitter circuit. By the way, the laser can be powered not only from batteries, but also from a battery. This is everyone's business.

To ensure that your device is assembled to a point when turned on, you can use an old Chinese pointer, replacing the laser from the pointer with one you assembled. The entire structure can be neatly packed into a case. This way it will look more beautiful and last longer. The body can be an unnecessary steel lantern. But it can also be almost any container. We choose a flashlight not only because it is stronger, but also because it will make your laser look much more presentable.

Thus, you have convinced yourself that it is enough for assembly powerful laser at home, neither deep knowledge of science nor prohibitively expensive equipment is required. Now you can assemble the laser yourself and use it for its intended purpose.

It is the most progressive, but also expensive technology. But with its help you can achieve results that are beyond the power of other metal processing methods. The ability of laser beams to give any material the desired shape is truly limitless.

The unique capabilities of the laser are based on the following characteristics:

• Clear directionality - due to the ideal directionality of the laser beam, the energy is focused at the point of impact with a minimum of losses,
• Monochromaticity - a laser beam has a fixed wavelength and a constant frequency. This allows it to be focused with ordinary lenses,
• Coherence – laser beams have a high level of coherence, so their resonant vibrations increase the energy by several orders of magnitude,
• Power - the above properties of laser beams ensure that the energy of the highest density is focused on a minimal area of ​​material. This allows you to destroy or burn through any material in a microscopically small area.

Design and principles of operation

Any laser device consists of the following components:

• energy source;
• working body that produces energy;
• an optical amplifier, a fiber-optic laser, a system of mirrors that amplify the radiation of the working element.

The laser beam produces point-by-point heating and melting of the material, and after prolonged exposure - its evaporation. As a result, the seam comes out with an uneven edge, evaporating material is deposited on the optics, which reduces its service life.

To obtain smooth thin seams and remove vapors, the technique of blowing melt products from the laser impact zone with inert gases or compressed air is used.

Factory laser models equipped with high-grade materials can provide good indentation rates. But for household use their price is too high.

Models made at home are capable of cutting into metal to a depth of 1-3 cm. This is enough to make, for example, parts for decorating gates or fences.

Depending on the technology used, there are 3 types of cutters:

• Solid state. Compact and easy to use. The active element is a semiconductor crystal. Low-power models have quite affordable prices.
• Fiber. Glass fiber is used as the radiation and pumping element. The advantages of fiber laser cutters are: high efficiency(up to 40%), long service life and compactness. Since little heat is generated during operation, there is no need to install a cooling system. It is possible to produce modular designs that allow you to combine the power of several heads. The radiation is transmitted via flexible optical fiber. The performance of such models is higher than solid-state ones, but their cost is higher.
• . These are inexpensive but powerful emitters based on the use chemical properties gas (nitrogen, carbon dioxide, helium). With their help you can weld and cut glass, rubber, polymers and metals with very high level thermal conductivity.

Homemade household laser

For execution repair work and manufacturing metal products in everyday life you often need to do laser cutting of metal yourself. Therefore, home craftsmen have mastered manufacturing and successfully use hand-held laser devices.

In terms of manufacturing cost, a solid-state laser is more suitable for household needs.

The power of a homemade device, of course, cannot even be compared with production devices, but it is quite suitable for use for domestic purposes.

How to assemble a laser using inexpensive parts and unnecessary items.

To make a simple device you will need:

• laser pointer;
• battery-powered flashlight;
• CD/DVD-RW writer (an old and faulty one will do);
• soldering iron, screwdrivers.

How to make a handheld laser engraver

Laser cutter manufacturing process

1. You need to remove the red diode from the computer disk drive, which burns the disk when recording. Please note that the drive must be a write drive.

After dismantling the upper fasteners, remove the carriage with the laser. To do this, carefully remove the connectors and screws.

To remove the diode, you need to unsolder the diode mountings and remove it. This must be done extremely carefully. The diode is very sensitive and can be easily damaged by dropping it or shaking it sharply.

1. From laser pointer remove the diode contained in it, and instead insert the red diode from the disk drive. The pointer body is disassembled into two halves. The old diode is shaken out by picking it up with the tip of a knife. Instead, a red diode is placed and secured with glue.
2. It is easier and more convenient to use a flashlight as a body for a laser cutter. The upper fragment of the pointer with a new diode is inserted into it. The glass of the flashlight, which is an obstacle to the directed laser beam, and parts of the pointer must be removed.

At the stage of connecting the diode to the power supply from batteries It is important to strictly observe the polarity.

1. At the last stage, they check how securely all the laser elements are fixed, the wires are connected correctly, the polarity is observed and the laser is level.

Laser cutter ready. Due to its low power, it cannot be used when working with metal. But if a device is needed, paper cutting, plastic, polyethylene and other similar materials, then this cutter is quite suitable.

How to increase laser power for metal cutting

You can make a more powerful laser for cutting metal with your own hands by equipping it with a driver assembled from several parts. The board provides the cutter with the required power.

The following parts and devices will be needed:

1. CD/DVD-RW writer (an old or faulty one will do), with a writing speed of more than 16x;
2. 3.6 volt batteries – 3 pcs.;
3. 100 pF and 100 mF capacitors;
4. resistance 2-5 Ohm;
5. collimator (instead of a laser pointer);
6. steel LED flashlight;
7. soldering iron and wires.

You cannot connect a current source to the diode directly, otherwise it will burn out. The diode draws power from current, not voltage.

The beams are focused into a thin beam using a collimator. It is used instead of a laser pointer.

Sold at an electrical goods store. This part has a socket where the laser diode is mounted.

The assembly of the laser cutter is the same as the model described above.

To remove static from the diode, wind it around it. Antistatic bracelets can be used for the same purpose.

To check the operation of the driver, use a multimeter to measure the current supplied to the diode. To do this, connect a non-working (or second) diode to the device. For most work homemade devices A current of 300-350 mA is sufficient.

If you need a more powerful laser, the indicator can be increased, but not more than 500 mA.

It is better to use it as a housing for homemade products led flashlight. It is compact and convenient to use. To prevent the lenses from getting dirty, the device is stored in a special case.

Important! A laser cutter is a kind of weapon, so it should not be pointed at people, animals, or given to children. Carrying it in your pocket is not recommended.

It should be noted that do-it-yourself laser cutting of thick workpieces is impossible, but it can cope with everyday tasks.

Hello ladies and gentlemen. Today I am opening a series of articles devoted to high-power lasers, because Habrasearch says that people are looking for such articles. I want to tell you how you can make a fairly powerful laser at home, and also teach you how to use this power not just for the sake of “shine on the clouds.”

Warning!

The article describes the production of a powerful laser (300mW ~ power of 500 Chinese pointers), which can harm your health and the health of others! Be extremely careful! Use special safety glasses and do not point the laser beam at people or animals!

On Habré, articles about portable Dragon Lasers, such as Hulk, appeared only a couple of times. In this article I will tell you how you can make a laser that is not inferior in power to most models sold in this store.

First you need to prepare all the components:

• - a non-working (or working) DVD-RW drive with a write speed of 16x or higher;
• — capacitors 100 pF and 100 mF;
• — resistor 2-5 Ohm;
• — three AAA batteries;
• - soldering iron and wires;
• — collimator (or Chinese pointer);
• — steel LED lamp.

This minimum required to make a simple driver model. The driver is, in fact, a board that will output our laser diode to the required power. You should not connect the power source directly to the laser diode - it will break down. The laser diode must be powered with current, not voltage.

A collimator is, in fact, a module with a lens that reduces all radiation into a narrow beam. Ready-made collimators can be purchased at radio stores. These immediately have a convenient place to install a laser diode, and the cost is 200-500 rubles.

You can also use a collimator from a Chinese pointer, however, the laser diode will be difficult to attach, and the collimator body itself will most likely be made of metallized plastic. This means our diode will not cool well. But this is also possible. This option can be found at the end of the article.

First you need to get the laser diode itself. This is a very fragile and small part of our DVD-RW drive - be careful. A powerful red laser diode is located in the carriage of our drive. You can distinguish it from a weak one by its larger radiator than that of a conventional IR diode.

It is recommended to use an antistatic wrist strap as the laser diode is very sensitive to static voltage. If there is no bracelet, then you can wrap the diode leads with thin wire while it waits for installation in the case.

According to this scheme, you need to solder the driver.

Don't mix up the polarity! The laser diode will also fail instantly if the polarity of the supplied power is incorrect.

The diagram shows a 200 mF capacitor, however, for portability, 50-100 mF is quite enough.

Before installing the laser diode and assembling everything into the housing, check the functionality of the driver. Connect another laser diode (non-working or the second one from the drive) and measure the current with a multimeter. Depending on the speed characteristics, the current strength must be chosen correctly. For 16 models, 300-350mA is quite suitable. For the fastest 22x, you can even supply 500mA, but with a completely different driver, the manufacture of which I plan to describe in another article.

Looks terrible, but it works!

Aesthetics.

A laser assembled by weight can only be boasted of in front of the same crazy techno-maniacs, but for beauty and convenience it is better to assemble it in a convenient case. Here it’s better to choose for yourself how you like it. I mounted the entire circuit into a regular LED flashlight. Its dimensions do not exceed 10x4cm. However, I do not recommend carrying it with you: you never know what claims the relevant authorities may make. It is better to store it in a special case so that the sensitive lens does not become dusty.

This is an option with minimal costs - a collimator from a Chinese pointer is used:

Using a factory-made module will allow you to get the following results:

The laser beam is visible in the evening:

And, of course, in the dark:

Maybe.

Yes, in the following articles I want to tell and show how such lasers can be used. How to make much more powerful specimens, capable of cutting metal and wood, and not just lighting matches and melting plastic. How to make holograms and scan objects to create 3D Studio Max models. How to make powerful green or blue lasers. The scope of application of lasers is quite wide, and one article cannot do it here.

Attention! Don't forget about safety precautions! Lasers are not a toy! Take care of your eyes!