It's no secret that each of us in childhood wanted to have such a device as a laser machine that could cut metal seals and burn through walls. In the modern world, this dream is easily becoming a reality, since it is now possible to build a laser with the ability to cut various materials.
Of course, at home it is impossible to make such a powerful laser machine that will cut through iron or wood. But with a homemade device, you can cut paper, plastic seal or thin plastic.
With a laser device, you can burn various patterns on sheets of plywood or on wood. It can be used as a backlight for objects located in remote areas. The scope of its application can be both entertaining and useful in construction and installation work, not to mention the realization of creative potential in the field of engraving on wood or plexiglass.
Read also:
How to do it right.
Review : their pros and cons.
cutting laser
Tools and accessories that will be required in order to make a laser with your own hands:
Figure 1. Diagram of a laser LED.
- faulty DVD-RW drive with a working laser diode;
- laser pointer or portable collimator;
- soldering iron and small wires;
- 1 ohm resistor (2 pcs.);
- capacitors for 0.1 uF and 100 uF;
- AAA batteries (3 pcs.);
- small tools such as a screwdriver, knife and file.
These materials will be quite enough for the upcoming work.
So, for a laser device, first of all, it is necessary to select a DVD-RW drive with a mechanical breakdown, since the optical diodes must be in good condition. If you do not have a worn drive, you will have to purchase it from people who sell it for parts.
When buying, keep in mind that most of the drives from the manufacturer Samsung are unsuitable for the manufacture of a cutting laser. The fact is that this company produces DVD drives with diodes that are not protected from external influences. The absence of a special housing means that the laser diode is subject to thermal stress and contamination. It can be damaged with a light touch of the hand.
Figure 2. Laser from a DVD-RW drive.
The best option for a laser is a drive from the manufacturer LG. Each model is equipped with a crystal with a different degree of power. This figure is determined by the burning speed of dual-layer DVDs. It is extremely important that the drive is a recording drive, since it contains an infrared emitter, which is needed to make a laser. The usual one will not work, since it is intended only for reading information.
The 16X DVD-RW is equipped with a 180-200mW red crystal. A 20X speed drive contains a 250-270mW diode. High-speed recorders of the 22X type are equipped with laser optics with a power of up to 300 mW.
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Disassembling a DVD-RW Drive
This process must be done with great care, because the internal parts are fragile and easily damaged. Having dismantled the case, you will immediately notice the necessary detail, it looks like a small piece of glass located inside the movable carriage. Its base must be removed, it is shown in Fig. 1. This element contains an optical lens and two diodes.
At this stage, it should immediately be warned that the laser beam is extremely dangerous for human vision.
With a direct hit on the lens, it damages the nerve endings and a person can remain blind.
The laser beam has a blinding property even at a distance of 100 m, so it is important to be careful where you point it. Remember that you are responsible for the health of others while such a device is in your hands!
Figure 3. LM-317 chip.
Before starting work, you need to know that the laser diode can be damaged not only by careless handling, but also by voltage drops. This can happen in a matter of seconds, which is why diodes operate on a constant source of electricity. When the voltage rises, the LED in the device exceeds its brightness norm, as a result of which the resonator is destroyed. Thus, the diode loses its ability to heat up, it becomes an ordinary flashlight.
The crystal is also affected by the temperature around it, when it falls, the laser performance increases at a constant voltage. If it exceeds the standard norm, the resonator is destroyed according to a similar principle. Less commonly, the diode is damaged by sudden changes, which are caused by frequent switching on and off of the device within a short period.
After removing the crystal, it is necessary to immediately bandage its ends with bare wires. This is necessary to create a connection between its voltage outputs. To these outputs you need to solder a small capacitor of 0.1 uF with negative polarity and 100 uF with positive polarity. After this procedure, you can remove the wound wires. This will help protect the laser diode from transients and static electricity.
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Nutrition
Before creating a battery for the diode, it must be taken into account that it must be powered from 3V and consumes up to 200-400 mA, depending on the speed of the recording device. Connecting the crystal directly to the batteries should be avoided as this is not a simple lamp. It can deteriorate even under the influence of ordinary batteries. The laser diode is an independent element, which is powered by electricity through a regulating resistor.
The power system can be adjusted in three ways with varying degrees of complexity. Each of them involves recharge from a constant voltage source (batteries).
The first method involves the regulation of electricity with a resistor. The internal resistance of the device is measured by detecting the voltage during the passage through the diode. For drives with a write speed of 16X, 200 mA will be sufficient. With an increase in this indicator, there is a possibility of spoiling the crystal, so you should stick to the maximum value of 300 mA. As a power source, it is recommended to use a telephone battery or AAA type batteries.
The advantages of this power scheme are simplicity and reliability. Among the shortcomings, one can note the discomfort with regular recharging of the battery from the phone and the difficulty of placing batteries in the device. In addition, it is difficult to determine the right moment to recharge the power supply.
Figure 4. LM-2621 chip.
If you use three AA batteries, this circuit can be easily equipped in a Chinese-made laser pointer. The finished design is shown in Figure 2, two 1 ohm resistors in series and two capacitors.
For the second method, the LM-317 chip is used. This way of arranging the power supply system is much more complicated than the previous one; it is more suitable for a stationary type of laser systems. The scheme is based on the manufacture of a special driver, which is a small board. It is designed to limit the electric current and create the necessary power.
The circuit for connecting the LM-317 chip is shown in Fig. 3. It will require elements such as a 100 ohm variable resistor, 2 10 ohm resistors, a 1H4001 series diode and a 100 microfarad capacitor.
The driver based on this circuit maintains electrical power (7V) regardless of the power source and ambient temperature. Despite the complexity of the device, this circuit is considered the easiest to assemble at home.
The third method is the most portable, making it the preferred method of all. It provides power from two AAA batteries, maintaining a constant level of voltage applied to the laser diode. The system retains power even when the batteries are low.
When the battery is completely discharged, the circuit will cease to function, and a small voltage will pass through the diode, which will be characterized by a weak glow of the laser beam. This type of power supply is the most economical, with an efficiency of 90%.
To implement such a power system, you will need an LM-2621 chip, which is housed in a 3 × 3 mm package. Therefore, you may encounter certain difficulties during the soldering of parts. The final size of the board depends on your skills and dexterity, since the details can be placed even on a 2 × 2 cm board. The finished board is shown in Fig. 4.
The inductor can be taken from a conventional power supply for a desktop computer. A wire with a cross section of 0.5 mm is wound on it with a number of turns up to 15 turns, as shown in the figure. The throttle diameter from the inside will be 2.5 mm.
Any Schottky diode with a value of 3 A is suitable for the board. For example, 1N5821, SB360, SR360 and MBRS340T3. The power supplied to the diode is adjusted by the resistor. During the tuning process, it is recommended to connect it with a 100 ohm variable resistor. When checking the performance, it is best to use a worn or unnecessary laser diode. The current power indicator remains the same as in the previous diagram.
Having chosen the most suitable method, you can upgrade it if you have the necessary skills for this. The laser diode must be placed on a miniature heatsink so that it does not overheat when the voltage rises. Upon completion of the assembly of the power system, you need to take care of installing optical glass.
The laser level is designed to determine the horizontal and vertical lines and planes during the construction of building structures and finishing. With this device, the geometry of the element can be observed with great accuracy. This is important for the strength and durability of the object under construction. But it is not always possible to purchase an industrial device. However, a skilled craftsman is able to create a laser level with his own hands. Consider how to do this, and whether it is possible to repair a broken level at home.
What is a laser level
In the case of this tool, LEDs are installed, which are sources of laser radiation. With the help of a bright luminous line, you can mark up any object both in the horizontal and vertical planes. Moreover, one person can easily cope with this work.
There are three types of lasers:
- prismatic;
- rotary;
- point.
Prism instruments create a linear beam projection. When a luminous line collides with an obstacle, the device captures the data and shows the desired markup. Such levels are equipped with an auto-leveling system, necessary to compensate for errors up to 6 °. The laser beam projection angle does not exceed 120°.
A prism laser level has a short beam range - an average of 10 to 50 m.
The prism laser level allows you to get horizontal and vertical planes that intersect at right angles
Rotary devices are classified as professional tools. They are equipped with point laser devices, but not fixed, but rotating with adjustable frequency. Designed for marking on very large areas, for example, on a construction site. The rotary level can project a 360° plane.
Rotary levels are characterized by a longer range of the laser beam - from 200 to 500 m.
By installing a rotary level in the middle of the room, you can mark all the necessary points around the entire perimeter
The point level is the simplest: the laser device is clearly fixed, and behind it is only a focusing lens. It directs the light flux to one point. Set up the device manually. Such levels are equipped with one or more lasers. In the latter case, they are directed in different directions, which makes it possible to transfer markings from several planes - walls, floors and ceilings of a large area. The laser beam projection angle does not exceed 160°.
The operating range of the point level is from 15 to 50 m, depending on the model.
Compact and versatile point laser for all leveling jobs over short distances
What is the device for?
The purpose of laser devices is diverse. They are required for the following types of work:
- breakdown of the territory and installation of equipment with control of the position horizontally and vertically;
- marking and determining the direction;
- surface leveling of the floor, walls and ceiling;
- arrangement of a concrete screed and assembly of floors with an adjustable level;
- carrying out communication highways;
- installation of bulkheads and hanging accessories;
- installation of stairs.
In the latter case, such an ability of the device as marking inclined planes is used. For example, you need to mount a railing on a flight of stairs. Having fixed a level with a laser on it, it is easier to install the railing parallel to the march.
To understand how to use the level, you can use the example of common construction and repair work.
Leveling floor, wall and ceiling surfaces
When carrying out such work, additional control marks will be needed. Then the laser beam is directed along the plane. According to the marks, the laser is rearranged for a more accurate determination of the evenness of surfaces.
When using a laser level and obtaining the same data, the floor is completely flat
Laying ceramic tiles
For such work, it is better to take a device with the function of cross-projection of rays in the horizontal and vertical. Thanks to them, even a novice master will be able to lay tiles flawlessly.
The intersection of the level lines is set to the center of the intended tile joints
Wallpapering
The gluing process itself is quite easy, but the use of a level allows you to make the process even easier. Focusing on the laser beam projected onto the wall, it is much more convenient to align the wallpaper.
Horizontal projection will contribute to the correct gluing of fillets and borders
Assembly of cabinet furniture
Even if there are even walls in the house, which is a rather infrequent occurrence, the interior can be spoiled by crookedly hung cabinets, shelves and other hanging accessories. And with the help of a laser that creates a circular level line, you will immediately see how to install hanging furniture without distortions.
The horizontal beam of the laser level will help with the installation of curtain rods
redevelopment
The Plane Builder simplifies this process. To determine the exact placement of drywall walls and partition elements, you will need to install the laser so that its projection on the floor, walls and ceiling is a mark for the intended partition.
When installing a metal frame under a plasterboard wall, the laser level is installed on the floor, the beam is directed upwards so that it marks the profile installation line
A simple device can be used outdoors only in cloudy weather or at dusk.
If a lot of external work is expected (digging trenches, laying communication lines, laying the foundation), it is better to get a professional plane builder with a beam visible in sunlight.
How to DIY
The idea of a do-it-yourself laser level is quite simple - the pointer is mounted on a movable platform. The use of such a mechanism allows marking by turning it at the same level by 360 °.
Necessary tools and materials
In addition to the laser pointer, you will need the following supplies:
- glue;
- saw blades for metal;
- jigsaw;
- a piece of corrugated plastic (for example, a headlight from a bicycle).
Walkthrough
You can make a laser level with your own hands from a pointer in just an hour:
- Let's improve the pointer. We saw off its tip, leaving the threaded part.
The laser pointer emits a dot
- From a piece of plastic we cut out a circle with a diameter, like the tip of a laser pointer.
If you pass a pointer beam through corrugated plastic, you get a line
- Glue the plastic circle to the tip of the pointer.
The place of gluing parts can be additionally coated with cold welding and turned
The imperfection of this version of the level is its one-way mobility - only horizontally.
The laser level must be fixed perpendicular to the plane
If you need to markup not only horizontally, but also vertically, you can try to mount a more advanced device:
- A hole is drilled in a wooden pole so that a long groove is obtained (or a ready-made plastic tube is taken). A pin, bolt or self-tapping screw is inserted into the hole in the center and fixed. The hardware is placed with the head down and fixed with an adhesive.
- A wide articulated fork is installed on the pin. To prevent it from loosening and scrolling, a rubber gasket is installed between it and the rack. A base made of plastic or wood is placed in the fork. A screw fastener passes through it, fixing the workpiece on both sides of the fork.
- The building level and an improved pointer are fixed on the base.
This type of assembly allows the device to change the location of the laser in the vertical direction. If you are smart and choose a suitable fork, it is realistic to assemble a device with a vertical turn of 270 °.
It should be borne in mind that the larger the fork size, the wider the workpiece will be required to create a stable position.
This device is collapsible. For the stability of the base, you will need to find a fork with a hinged part of the desired section.
If there is no suitable plug, you can make it yourself from a durable metal-plastic ring of the desired section.
You will need to drill three holes: two from the sides, opposite each other, and the third is exactly in the center between the two future “teeth” of the fork. Then the ring is cut so that a semicircle with three holes is obtained.
A homemade laser can be modified: screw an ordinary nut or “lamb” onto the mounting screw, which allows you to quickly loosen and fix the base, as well as change the direction of the laser up or down.
Video: do-it-yourself laser level
Setup and Calibration
After assembling a homemade device, you need to set up the laser level with your own hands. It is necessary to check it - to calibrate for the accuracy of measurements. To carry out the test, you will need an additional bubble level. Calibration is carried out as follows:
- The device is placed in the center of the room and marks are made on opposite walls at the point of intersection of the planes.
- The level is transferred to one of the walls at a distance of approximately half a meter, another mark is made above or below the first.
- The device turns to the opposite wall, a mark is made.
- The distance between the marks on both walls is measured and the error is calculated.
For example, the difference between the marks on the first wall is 4 mm, and on the second - 3 mm. As a result, the error is 1 mm. If it is larger, then the device requires adjustment.
The self-assembled measuring device can be placed on a tripod or adjustable pedestal, which will give the product convenience and functionality.
To calibrate the vertical, mark two points in the vertical plane and check the marks on the bubble level.
If no deviations are noticed, then the plane builder is ready to work. If there is a discrepancy in the readings, a home-made laser device is adjusted by changing the location of the platform or swivel fork.
How to repair
Due to the failure of the laser mechanism, it may show the wrong level or not work at all.
Homemade fixture needs repair:
- in case of diode failure;
- sticking or failure of buttons and switches;
- when the emitter malfunctions, when the laser does not glow or the beam is very dim.
Most often, repair of laser levels is required after the device has been dropped. In this case, the settings are lost, which leads to the issuance of incorrect indicators by the device.
If you need to repair a homemade laser, you need to disassemble the device and reassemble it. If the problem is in the pointer, it is easier to replace it with a new one.
In order to avoid repairing a homemade laser level, it is important to be careful when working with it, especially on the street.
To build even planes on large-scale construction sites, industrial levels with a large operating range have been created. For minor repairs, you can make a laser level with your own hands.
Man has learned many technical inventions by observing natural phenomena, analyzing them and applying the acquired knowledge in the surrounding reality. So man got the ability to kindle a fire, created a wheel, learned to generate electricity, got control over a nuclear reaction.
Unlike all these inventions, the laser has no analogues in nature. Its emergence was associated solely with theoretical assumptions within the framework of emerging quantum physics. The existence of the principle that formed the basis of the laser was predicted at the beginning of the 20th century by the greatest scientist Albert Einstein.
The word "laser" appeared as a result of the reduction of five words describing the essence of the physical process to the first letters. In the Russian version, this process is called "amplification of light with the help of stimulated emission."
According to the principle of its operation, the laser is a quantum generator of photons. The essence of the phenomenon underlying it is that under the action of energy in the form of a photon, an atom emits another photon, which is identical to the first one in the direction of motion, its phase and polarization. As a result, the emitted light is amplified.
This phenomenon is impossible under conditions of thermodynamic equilibrium. Various methods are used to create induced radiation: electrical, chemical, gas, and others. Lasers used in the home (laser disk drives, laser printers) use semiconductor method stimulation of radiation under the action of an electric current.
The principle of operation is the passage of an air flow through the heater into the hot air gun tube and, having reached the set temperatures, it enters the part to be soldered through special nozzles.
In the event of a malfunction, the welding inverter can be repaired by hand. You can read repair tips.
In addition, a necessary component of any full-fledged laser is optical resonator, the function of which is to amplify the beam of light by reflecting it multiple times. For this purpose, mirrors are used in laser systems.
It should be said that creating a real powerful laser with your own hands at home is unrealistic. For this, it is necessary to have special knowledge, carry out complex calculations, and have a good material and technical base.For example, laser machines that can cut metal are extremely hot and require extreme cooling measures, including the use of liquid nitrogen. In addition, devices based on the quantum principle are extremely capricious, require the finest tuning and do not tolerate even the slightest deviation from the required parameters.
Required Components for Assembly
To assemble a laser circuit with your own hands, you will need:
- Rewritable DVD-ROM (RW). It incorporates a red laser diode with a power of 300 mW. You can use laser diodes from BLU-RAY-ROM-RW - they emit violet light with a power of 150 mW. For our purposes, the best ROMs are those with faster write speeds: they are more powerful.
- Pulse NCP1529. The converter outputs a current of 1A, stabilizes the voltage in the range of 0.9-3.9V. These indicators are ideal for our laser diode, which requires a constant voltage of 3V.
- Collimator for obtaining an even beam of light. Now on sale are numerous laser modules from various manufacturers, including collimators.
- Output lens from ROM.
- Housing, for example, from a laser pointer or flashlight.
- Wires.
- Batteries 3.6 V.
To connect the parts you will need. In addition, you will need a screwdriver and tweezers.
How to make a laser from a disk drive?
The procedure for assembling a simple laser consists of the following steps.
It's not at all difficult to do. The difference is in the number of contacts. In a pass-through switch, unlike a simple one, there are three contacts instead of two.
In this way, the simplest laser can be assembled. What can such a handicraft "light amplifier" do:
- Light a match from a distance.
- Melt plastic bags and thin paper.
- Emit a beam at a distance of more than 100 meters.
Therefore, you need to use such a device carefully: do not shine it on reflective surfaces (mirrors, glasses, reflectors) and, in general, be extremely careful - the beam can cause harm if it hits the eye even from a distance of one hundred meters.
Do-it-yourself laser on video
Making a powerful burning laser with your own hands is a simple task, however, in addition to the ability to use a soldering iron, care and accuracy of the approach will be required. It should be noted right away that deep knowledge of electrical engineering is not needed here, and you can make a device even at home. The main thing during work is the observance of safety precautions, since exposure to a laser beam is detrimental to the eyes and skin.
The laser is a dangerous toy that can be harmful to health if used carelessly. Do not aim the laser at people or animals!
What will be required?
Any laser can be divided into several components:
- luminous flux emitter;
- optics;
- source of power;
- current power stabilizer (driver).
To make a powerful homemade laser, you will need to consider all these components separately. The most practical and easy to assemble is a laser based on a laser diode, and we will consider it in this article.
Where can I get a diode for a laser?
The working body of any laser is a laser diode. You can buy it at almost any radio store, or get it from a non-working CD drive. The fact is that the inoperability of the drive is rarely associated with the failure of the laser diode. Having a broken drive available, you can get the desired element at no extra cost. But you need to take into account that its type and properties depend on the modification of the drive.
The weakest laser operating in the infrared range is installed in CD-ROM drives. Its power is only enough to read CDs, and the beam is almost invisible and is not able to burn through objects. The CD-RW has a more powerful laser diode, suitable for burning, and rated for the same wavelength. It is considered the most dangerous, as it emits a beam in the spectrum invisible to the eye.
The DVD-ROM drive is equipped with two weak laser diodes, which only have enough energy to read CDs and DVDs. The DVD-RW burner has a high power red laser. Its beam is visible in any light and can easily ignite some objects.
The BD-ROM has a purple or blue laser, which is similar in parameters to the DVD-ROM counterpart. From BD-RE writers you can get the most powerful laser diode with a beautiful violet or blue beam that can burn. However, it is quite difficult to find such a drive for disassembly, and a working device is expensive.
The most suitable is a laser diode taken from a DVD-RW disc burner. The highest quality laser diodes are installed in LG, Sony and Samsung drives.
The higher the write speed of a DVD drive, the more powerful the laser diode installed in it.
Drive disassembly
With the drive in front of them, the first thing to do is remove the top cover by unscrewing 4 screws. Then the movable mechanism is removed, which is located in the center and is connected to the printed circuit board with a flexible cable. The next target is a laser diode reliably pressed into a radiator made of aluminum or duralumin alloy. Before dismantling it, it is recommended to provide protection against static electricity. To do this, the leads of the laser diode are soldered or wrapped with a thin copper wire.
Further, two options are possible. The first involves the operation of the finished laser in the form of a stationary installation together with a standard radiator. The second option is to assemble the device in the body of a portable flashlight or laser pointer. In this case, you will have to apply force to bite through or cut the radiator without damaging the radiating element.
Driver
The power supply of the laser must be taken responsibly. As with LEDs, this must be a constant current source. There are many circuits on the Internet that are powered by a battery or battery through a limiting resistor. The sufficiency of such a solution is doubtful, since the voltage on the battery or battery varies depending on the level of charge. Accordingly, the current flowing through the laser emitting diode will deviate greatly from the nominal value. As a result, the device will not work efficiently at low currents, and at high currents it will lead to a rapid decrease in the intensity of its radiation.
The best option is to use the simplest current stabilizer built on the basis. This microcircuit belongs to the category of universal integrated stabilizers with the ability to independently set the current and voltage at the output. The microcircuit operates in a wide range of input voltages: from 3 to 40 volts.
An analogue of the LM317 is the domestic chip KR142EN12.
For the first laboratory experiment, the scheme below is suitable. The calculation of the only resistor in the circuit is carried out according to the formula: R = I / 1.25, where I is the rated laser current (reference value).
Sometimes, at the output of the stabilizer, a polar capacitor of 2200 uFx16 V and a non-polar capacitor of 0.1 uF are installed in parallel with the diode. Their participation is justified in the case of supplying voltage to the input from a stationary power supply, which can miss an insignificant variable component and impulse noise. One of these circuits, designed to be powered by a Krona battery or a small battery, is presented below. 
The diagram shows the approximate value of the resistor R1. For its exact calculation, you must use the above formula.
Having assembled the electrical circuit, you can make a preliminary inclusion and, as proof of the circuit's operability, observe the bright red scattered light of the emitting diode. Having measured its real current and case temperature, it is worth thinking about the need to install a radiator. If the laser is to be used in a stationary installation at high currents for a long time, then passive cooling must be provided. Now, to achieve the goal, there is very little left: to focus and get a narrow beam of high power.
Optics
In scientific terms, it's time to build a simple collimator, a device for obtaining beams of parallel light beams. An ideal option for this purpose would be a standard lens taken from the drive. With its help, you can get a fairly thin laser beam with a diameter of about 1 mm. The amount of energy of such a beam is enough to burn through paper, fabric and cardboard in a matter of seconds, melt plastic and burn wood. If you focus a thinner beam, then this laser can cut plywood and plexiglass. But it is quite difficult to adjust and securely fix the lens from the drive due to its small focal length.
It is much easier to build a collimator based on a laser pointer. In addition, a driver and a small battery can be placed in its case. The output will be a beam with a diameter of about 1.5 mm of a smaller burning effect. In foggy weather or with heavy snowfall, incredible lighting effects can be observed by directing the light flux into the sky.
Through the online store you can purchase a ready-made collimator, specially designed for mounting and adjusting the laser. Its body will serve as a radiator. Knowing the dimensions of all the components of the device, you can buy a cheap LED flashlight and use its body.
In conclusion, I would like to add a few phrases about the dangers of laser radiation. First, never direct the laser beam into the eyes of people or animals. This leads to severe visual impairment. Secondly, wear green goggles while experimenting with the red laser. They prevent the passage of most of the red component of the spectrum. The amount of light that passes through the glasses depends on the wavelength of the radiation. Looking at the laser beam from the side without protective equipment is only allowed for a short time. Otherwise, pain in the eyes may appear.
Read also
Sometimes you can make something really incredible and useful from unnecessary things stored at home. Do you have an old DVD-RW (writer) drive lying around at home? We will show you how to make a powerful laser at home by borrowing elements from it.
Safety
The device we end up with is not a harmless toy! Before you make a laser, take care of your safety: hitting the beam in the eyes is detrimental to the retina, especially if the invention is powerful. Therefore, we advise you to carry out all work in special protective glasses that will save your eyesight if something goes wrong and you accidentally direct the laser beam into yourself or a friend's eyes.
When using the laser in the future, remember these simple safety precautions:
- Do not aim the laser beam at flammable or explosive objects.
- Do not shine on reflective surfaces (glasses, mirrors).
- Even a laser beam fired from a distance of up to 100 m poses a danger to the human and animal retinas.
Working with the laser module
The main thing we need is a burner. Note that the higher the write speed, the more powerful our DVD laser will be. It goes without saying that after removing the laser module, the equipment will become inoperative, so disassemble only such a device that you no longer need.
And now we start:
The first part of our work is over. Let's move on to the next important step.
Assembling the device circuit
We need a circuit in order to control the power of our device. Otherwise, it will simply burn out on the first use. You will see the drawing for the laser below.
For our device, hanging mounting is quite suitable. And now let's move on to providing power to a do-it-yourself laser.
Device power supply
We will need a minimum of 3.7 V. Old batteries from mobile phones, penlight batteries can provide this. It is only necessary to connect them in parallel with each other. To check the operation of the device or a stationary laser pointer, a stabilization power supply is suitable.
At this stage, you can already test the operation of the device. Point it at the wall, floor and turn on the power. You should see a bunch of bright reddish color. In the dark, it looks like a powerful infrared flashlight.
You can see that while the glow is far from the laser: the beam is too wide; he asks to be focused. This is what we will do next.
Lens for focusing the laser beam
To adjust the focal length, you can get by with a lens borrowed from the same DVD-RW drive.
Now reconnect the power to the device, directing its light to any surface through this lens. Happened? Then we move on to the final stage of work - placing all the elements in a rigid case.
Case manufacturing
Many, advising how to make a laser, say that the easiest way is to place the module in a case from a small flashlight or a Chinese laser pointer. Where, by the way, there is already a lens. But let's analyze the situation, if neither one nor the other was at hand.
As an option - place the elements in an aluminum profile. It is easily sawn with a hacksaw, modeled with pliers. You can also add a small finger battery here. How to do this, the photo below will guide you.
Be sure to insulate all contacts. The next step is fixing the lens in the housing. It is easiest to mount it on plasticine - so you can adjust the most successful position. In some cases, a better effect is achieved if you turn the lens towards the laser diode with the convex side.
Turn on the laser and adjust the beam clarity. Once you are satisfied with the results, lock the lens into the housing. Then close it entirely, for example, tightly wrapping it with electrical tape.
How to make a laser: an alternative way
We will offer you another, somewhat different way to make a homemade powerful laser. You will need the following:
- DVD-RW drive with a recording speed of 16x or more.
- Three finger batteries.
- Capacitors 100 mF and 100 pF.
- Resistor from 2 to 5 ohms.
- Wires.
- Soldering iron.
- Laser pointer (or any other collimator - this is the name of the module with a lens).
- LED steel lantern.
Now let's see how to make a laser using this method:
- Remove the laser module located in the device carriage from the drive in the way already described. Remember to protect it from static electricity by wrapping the outputs with thin wire or wearing an antistatic wrist strap.
- According to the above scheme, solder the driver - the board that will bring our homemade product to the desired power. Pay great attention to polarity so as not to damage the sensitive laser diode.
- In this step, we will test the performance of the newly built driver. If the laser module is from a model with a speed of 16x, then a current of 300-350 mA is enough for it. If higher (up to 22x), then stop at 500mA.
- After you have verified that the driver is suitable, it must be placed in the case. It can be either a base from a Chinese laser pointer with a lens already mounted, or a more suitable housing from an LED flashlight.
Laser testing
And here is what you were interested in how to make a laser for. Let's move on to practical testing of the device. In no case do not spend it at home - only on the street, away from fire and explosive objects, buildings, dead wood, heaps of garbage, etc. For experiments, we need paper, plastic, the same electrical tape, plywood.
So let's start:
- Place a sheet of paper on asphalt, stone, brick. Aim an already well-focused laser beam at it. You will see that after a while the leaf will begin to smoke, and then it will completely light up.
- Now let's move on to plastic - it will also begin to smoke from exposure to a laser beam. We do not recommend conducting such experiments for a long time: the combustion products of this material are very toxic.
- The most interesting experience is with plywood, a flat plank. A focused laser can burn a certain inscription, drawing on it.
A home laser is, of course, a delicate work and a capricious invention. Therefore, it is quite possible that your craft will soon fail, as certain storage and operating conditions are important for it, which cannot be provided at home. The most powerful lasers, which can easily cut metal, can only be obtained in specialized laboratories; naturally, they are not available to amateurs. However, a conventional device is also very dangerous - directed from a long distance into the eyes of a person or animal, close to a flammable object.