Power supply circuit for a laser diode for an engraver. Do-it-yourself laser from a CD-DVD drive. There are different types of laser diodes. The main ones are made on particularly thin layers. Their structure is capable of creating radiation only in parallel. But if you are a waveguide

Self-assembled laser engraver/cutter based on a 2.5 Watt laser module.
In short - XY-kinematics, Marlin firmware and D8-L2500 laser module. The engraver turned out just right - he knows how to burn, both with dots and lines, and most importantly - to cut!

Let me immediately remind you about TB: when working with a laser, use glasses (special ones, taking into account the wavelength of the laser), do not point it at your eyes. The laser is very powerful - even a small reflected radiation can seriously damage the retina.

So, recently I have been struggling to improve the Neje DK-5 laser engraver in order to increase (primarily) the working area and power for processing various materials. In the end, I came to the conclusion that it would be easier to make another one, in the image of simple Chinese engravers on the profile.

As a basis, I took a Chinese kit on an aluminum structural profile 2020 and 2040. Looking ahead, I will say that practice has shown that it is easier to do everything on the same profile 2040, since the ease of installation and rigidity of the frame significantly increases (it is easier to attach elements of body panels to a double profile , legs, cable channels).

The basis of any laser engraver is the laser module. I had experience working with diodes torn from all kinds of equipment, as well as with a module from Neje, but I wanted something more. The Chinese sell all-in-one solid-state laser assemblies: a module in the form of an aluminum radiator of a cylindrical (less often) or rectangular shape (most often). Inside the radiator there is a cylinder with a laser diode, from which two contacts protrude for connecting the supply current. Also installed inside the laser module (and filled with a certain substance) is a current driver for the diode, most often CC (continuous current), less often a driver with support for TTL signals to control the laser power. Often there is a cooling fan on the side or at the end of the radiator. At the other end of the laser output there is a focusing or collimating lens (depending on the purpose of the module). Power supply is usually 5V or 12V.
Here's an example of what's inside (photo not mine, from the open air).

Solid-state laser modules (diode) range from hundreds of milliwatts (for example, 0.3 W) to several units (for example, 5.5 Chinese watts). The more power, the higher the price, and for powerful modules the price is so high that it is easier to consider installing a CO2 tube, but that is a completely different story. Keep in mind that Chinese watts do not always correspond to reality (it is very difficult to estimate the real radiation power). And you can easily buy the same laser diode, labeled 5.5W, 8W or 10W. Perhaps they will differ in increased current to the diode itself, which greatly (several times) reduces the life of the diode.

Since I wanted not only to burn wood, but also to cut anything (plastic, plywood, cardboard, etc. - but not metals!), the Neje module was no longer enough for me, especially since the ones torn from CDs don’t roll, and they burn out quickly. It was decided to look for and purchase a several-watt laser module from China; I mainly chose from 450 nanometer laser modules (one of the most affordable).
There are the following types of laser heads on the girbest:

1. 2.5W 12v;
2. 0.5 W 12V;
3. 0.5 W 5 V.
All lasers are 445nm (violet laser), with cooling fan and power supply included.

In addition to the difference in power, it is obvious that the supply voltage is also different. Modules for 5V are very convenient for power supply with power banks/batteries, as well as for ready-made cases with 5V drives. Don't forget that the fan should also be 5V.
When powering stepper motors from 12V, it makes sense to purchase a 12V laser module in order to unify the power supply for the engraver (that is, only 1 12V power supply is required). This is exactly my option. Included with the D8-2500 is a 12V and 5A power supply, which is clearly enough for the laser diode, and in addition remains to power the Ramps electronics and servos.

In the end, I ordered 2.5W/12V. This is what they sent:

Here are some photos of the laser module itself.

Turned on the laser to check the power circuits and correct connections. Somehow I didn’t realize to install an absorbing substrate, and ended up burning my photophone.

So, I’ll tell you about my engraver project, which resulted in an upgrade of my Neje. A kind of mess from an axe. I twisted the laser and removed the electronics. I realized that you can’t make porridge from this. Replaced electronics and laser. As a result, I decided to leave Neje alone and put it away.

I would like to say that there are ready-made frames for installing lasers - XY plotters. But I decided to assemble the frame myself, especially since it is not so difficult.
The idea was very simple - the use of a 2020/2040 structural profile as a frame and guides for a simple A3 engraver, like in Chinese engravers. Rigidity is ensured by special (standard) connections for the structural profile. (internal connectors, corners). Profile dimensions – dimensions of the printed area (minus the carriage). The format was chosen to be slightly larger than an A4 sheet with the expectation of small-sized materials. After Neje with its 3.5x3.5, the difference is simply huge.

About electronics: there are options for RAMPS/LCD/SD/Marlin or CNCshield/GRBL. I removed the stepper motors from the old device (nema17 - can be purchased, they are standard. Great efforts are not needed, since the laser head is lightweight / I think that with small axes you can use inexpensive nema17 type 17H2408. I ordered a profile cut to size and fittings (corners and hardware), plus rollers for carriages.

In any case, if you are interested in assembling a printer yourself, then there are practically no problems finding drawings for printing on a printer (stl) or drawings for cutting acrylic.

A definite plus of the D8-L2500 laser module kit is the presence of a 12V 5A power supply, which is very convenient. I will power the steppers from the same power supply.

What is required for assembly

1 Laser head Engraver/burner - 1 pc.
2 Power supply 12V For powering the laser and drives (1 piece, included in the kit
laser)
3 5V power supply To power the electronics board (optional)
4 2040 profile longitudinal parts of the frame, X-axis - 2 pieces x 420mm
5 2040 profile transverse parts of the frame - 2 pcs x350mm
6 2040 profile Crossbar Y axis - 1 piece x380mm
7 Nema17 Two in X, one in Y - 3 pcs.
with drive ones not necessarily powerful
gears
8 Belt GT2-6mm Two sections in X, one in Y -1.5 meters approximately
9 Limit switches Extreme positions of X-Y axes - 2 pcs.
10 RAMPS 1.4 Control set - 1 piece (*took everything as a set)
11 Ardu Mega R3 electronics* - 1 piece
12 Display+SD shield+cables - 1 pc.
13 A4988 driver, with radiators - 2 pcs.
14 Set of hardware (screws M3, M4, M5, nuts M3 - Set
M4, M5, T-nuts, washers, etc.) For fastening the frame, straps,
engines, for assembling carriages,
etc.
15 Internal corners For fastening frame corners - 4 pcs.
16 Legs or stands In the corners - 4 pcs.
17 Set of wires -Kit
18 Cable channels** - 1.5 meters approximately
19 Rollers For carriages *** 12 (three carriages of 4 pcs each)

* Electronics can be replaced with Arduino Uno/Nano and CNC shield with drivers (A4988/DRVxxxx)
**There is also a spiral cable channel.
*** You can use 3 rollers, or different rollers (by diameter), depending on the selected carriages.

In terms of hardware, I can only give you an approximate estimate; I took a stock of different denominations, then actually looked at what would fit. I recommend buying in wholesale or ordering from Ali (I ended up spending several times more buying at retail than I would have taken a couple of lots on Ali for 50-100 nuts and screws).
If the carriages are made of acrylic, you don’t have to make a double one - I played it safe, because of this the thickness of the carriage has increased and the working area has decreased by almost 6 cm. You can also take the rollers more conveniently, with a pressed-in M5 bushing.
The original OpenBuilds version assumed the use of only 3 rollers - two running ones and one smaller one for pressing.

To make the carriages lighter, instead of several washers, I used printed bushings. Everything is selected and done in three minutes, and printed in about the same time. You can use washers or make other spacers. When designing, it is better to take into account a small margin in the size of the holes, plus, due to plastic shrinkage.

This is what happened.

Second pass on corrugated cardboard. I made two passes due to the thickness. So cardboard cuts well. Unfortunately, the second order with wire extensions for servos and a cable duct did not arrive in time - I now have a limited work area - the wires are stretched, so there will be no test on a large canvas (or I’ll post it later).

A small minus - the work of such an engraver in an apartment is evil))) There is a lot of smoke from cardboard and wood. For this reason, I did not cut plastic and acrylic. Need a good hood.

The plans are to make legs, something like a body, and put the wires into the channels (it is possible to run the wires inside the profile or along grooves, with them secured with clips). Ventilation, exhaust hood and housing are very necessary.
So far the plans are to adapt the laser module to work with PWM by replacing the driver with an external one.
And I'm looking for software to convert images to LCD. What I tried did not help me.
Another thought is that you can add a third axis with a gentle stroke. This will allow for more flexible adjustment to thick materials.

Conclusions
In general, the purchase of this module freed up my time, which was spent on altering diodes without housings. There is no need to select a lens and power supply for each one, or shove everything into the body. The cost of the module is quite high, but if you compare the cost of the finished design of a laser engraver of this type, then in the end the benefits are obvious. The fact is that the cost of a laser is more than half the cost of the entire engraver. The rest is the cost of the profile, engines and electronics (little things).

Many people had laser pointers as children, which could be purchased in toy stores. But with the development of modern technologies, it became possible to create such a laser with your own hands. To do this, you just need a faulty DVD drive (it is important that the LED itself remains working), a screwdriver and a soldering iron.

It should be remembered that it is better to use a non-working DVD to create a laser! This is due to the fact that after disassembling and removing the LED, it fails. Do not forget that such a laser from the drive is much more powerful than a conventional pointer and can cause irreparable harm to health, so you should never direct the beam at a person or animal.

When the beam of such a device is pointed at the human eye, the retina is burned out, and the person may partially or completely lose vision.

So, let's create a laser from a DVD drive with our own hands. To do this, you need to carefully unscrew the bolts on the back of the case to get to the LED of the future laser. Under the cover there is a unit that drives the carriage. In order to remove it, you need to unscrew the screws and disconnect all the cables. Then the carriage is removed.

Now you need to disassemble it, for which you need to unscrew many screws. Next, two LEDs will be detected. One of them is infrared, it is responsible for reading information from the disk.

You need red, with the help of which information is burned onto the disk. There will be a circuit board attached to the red LED. In order to disable it, you need to use a soldering iron. To check the functionality of the diode, it is enough to connect two AA batteries to it, but it is important to take into account their polarity. Remember that the laser diode is fragile, so you need to be very careful with it.

Next, you need to purchase any laser pointer. When creating a laser from a DVD drive with your own hands, use it as a “donor” for the case. After purchase, you need to carefully unscrew the pointer into two parts and remove it from the upper half. You can use a knife to do this. It is important to do everything carefully, because the diode may be damaged. Using a small screwdriver, select the emitter. Using hot melt adhesive, install the new LED into the housing. And to ensure that it is firmly installed, you can use pliers, pressing them on the edges of the diode.

The DIY laser from a DVD drive is almost ready. Before you run it, you need to check if the polarity is correct. Now you can safely connect the power. After the first launch, you may need to adjust the focus. Next, you can install the pointer in the flashlight and connect AA batteries. Do not forget that the laser can burn through various objects, so you need to remove the plexiglass from the diffuser.

A well-tuned drive can not only burn paper or light matches, but also leave a mark on plexiglass, explode balls (it is better if they are black) and leave visible marks on plastic. If you install a diode in the plotter head, you can engrave on plexiglass.

Laser pointers, which many of us played with as children, can be made with your own hands at home. Or you can create a fairly powerful device that can burn objects with its beam. And for this we need a laser diode, which can be removed from the DVD-RW player.

Laser diode taken from DVD

From this article you will learn the sequence of work for creating a homemade laser device with significant power.

What will you need at work?

To make a laser yourself, you need to use a red laser diode (650nm). It can be removed from a broken or old DVD-RW drive.

Pay attention! If the device is broken, then there is a high probability that its laser diode remains in working order. Therefore, it is quite suitable for our work.

You can also use a CD-RW drive. Some even use a Blu-ray drive. But in this case, the CD-RW drive will be characterized by an infrared invisible ray (780nm), and the Blu-ray drive will be characterized by a violet ray (405nm).
In addition, you will also need tools to disassemble the DVD-RW drive.

Let's talk about the player

To remove the laser diode taken from the DVD-RW drive, you need to carefully disassemble the device. To do this, you need to understand drive devices. It is placed in a special metal heat-removing housing, which is additionally placed in another metal base. It depends on you whether it is worth removing the device from such a housing or not.

Pay attention! When disassembling a DVD-RW device, you should not take out the loose discs.

DVD-RW drive

You can also leave the radiator in the case and remove the base. This affects the quality of the heat sink, which is necessary for our laser installation. Some experts argue that when the LED supplies a non-pulse current, the created heat sink will not be enough for the carriage. This statement will be correct for certain drive models, as well as if it is necessary to obtain maximum power.
DVD-RW has two laser diodes built into it. Of these, one is infrared and is used for recording and playing CDs. And the second one is red and is used for playing and recording DVDs. As you can see, if you wish, you can make two lasers with your own hands.

Pay attention! The BD-RE drive model has as many as three diodes built in. But modern models of this type of device use dual LEDs installed on one chip.

In such assemblies, you cannot simultaneously connect infrared and red diodes if the current is large.

Things to remember when working

When creating a laser with your own hands, you must remember that the laser diode can be damaged by static electricity. Therefore, to ensure normal operation of this element, three legs are needed
wrap with bare wire.

Pay attention! Do not direct the laser beam into the eyes. It should also not be pointed at reflective surfaces. This can lead to complete or partial loss of vision.

The requirements that exist for working with lasers are also relevant for infrared radiation. After all, both of these radiations have a powerful burning ability.

Red laser beam

In addition, you need to know that the laser diode must be powered with a certain current. If the supply current exceeds a certain threshold, this may lead to overheating of the diode. As a result, it will either burn out completely or glow like a standard LED.
In order for the current to have the correct values, you need to use a certain laser assembly circuit. In this case, it must have a driver. Let's look at several laser assembly schemes using a laser diode taken from a DVD-RW drive.

First build option

In this situation, it is necessary to use the following scheme for assembling a device based on a laser diode removed from the DVD-RW drive.

Assembly diagram

The disadvantage of this scheme is the presence of a situation where the battery voltage sags at the time of discharge, which causes a linear drop in the laser brightness.
To assemble a laser system according to the above diagram, you need not only a diode, but also capacitors with any voltage (from 3V). In the diagram they are marked with the icon C1 and C2. The capacity of the first capacitor should be 0.1 µF, and the second - 100 µF. They will protect the diode from static electricity and also ensure a smooth transition of processes. Once the capacitors have been connected to the laser light source, the wire can be removed from the lead. When connected to a diode, one of the terminals on the housing will supply a minus. At the same time, the second conclusion will be a plus, and the third one will not apply. The location of the pluses is shown quite well in the second diagram, which will be described below.
It is worth knowing that a plus is supplied to the body of some diodes (for example, 808nm LED). Dual models are characterized by the presence of a middle pin for the common minus (G), and an outer pin - C for powering DVD, CD, D.
This circuit can be powered from a mobile battery or 3 AA batteries.

Pay attention! When assembling the circuit, it is necessary to take into account that the battery voltage may differ from the specified one. This is especially noticeable immediately after charging it. At 3.7 V there may be 4.2 V. In this regard, the battery must be checked with a multimeter.

In this case, the current can also have different values. For example, at the appropriate write speeds of a DVD-RW drive, the laser diode can have the following values ​​of parameters such as power and current:

• at speed 16, the power will be 200 mW, and the current will be 250-260 mA;
• at speed 18, the power will be 200 mW, and the current will be 300-350 mA;
• at speed 20, the power will be 270 mW, and the current will be 400-450 mA;
• at speed 22, the power will be 300 mW, and the current will be 450-500 mA;
• at speed 24 the power will be 300mW and the current will be 450-500mA.

Infrared diode

The infrared diode of the CD-RW drive will have a power of 100-200 mW. For comparison, violet in BLU-RAY RW is from 60 to 150 mW, and in non-writing models - 15 mW.
Before assembling this circuit, when using a DVD drive laser diode, you need to find out what resistance is required for resistor R1. To do this, you can use the formula R1=(Uin.-Ufall.)/I, in which:

• Uin. – voltage coming from the battery;
• Upd. - voltage drop that the diode receives. The red diode should have approximately U drop. equal to 3 V. This voltage is suitable for a low-power non-writing DVD drive. For infrared diode Upad. will be approximately 1.9 V, and for violet or blue - 5.5 V and 4-4.4 V, respectively;
• I - current strength. It can be found out from a special table.

When assembling a laser, many experts recommend using resistors with a higher resistance than what was obtained in the calculations. This will protect the semiconductor from excessive current. Using a multimeter, you can further reduce the resistance.

Second assembly option

In this case, when assembling the laser system, you must be guided by the following diagram.

Laser installation diagram

This scheme, unlike the one described above, does not have problems with a decrease in laser brightness. This problem was solved by using in the circuit
a special adjustable stabilizer (for example, KREN12A or its common analogue LM317T). In this case, you need to know that the selected stabilizer is compensatory. It supplies about 1.4V more voltage than required. As a result, in order to get 3 V to the laser diode in the circuit, you need to apply from 4.4 V to 37 V. In this case, the output will still be 3 V (of course, provided that the resistors are correctly selected).
If less than 4.4 V is supplied to the circuit, the laser brightness will begin to decrease, which is typical for the first circuit. As a result, a situation similar to a battery discharge will arise. For 780nm diodes, the circuit will need to be supplied from 3.8 V to 37 V. Therefore, in such a situation, this circuit may be ineffective, since the current-voltage characteristic here will fluctuate greatly depending on the ambient temperature. And this can lead to a burnout of the circuit if the increase in current value cannot be detected in time.

Pay attention! Some experts believe that this effect is characteristic of blue laser diodes.

To avoid overheating, it is necessary to measure the current before the light source is completely warmed up. This will eliminate the risk of increasing the maximum permissible current value.
Experts recommend using resistance for R1 in Ohm value. And to determine parameter R2, you must use the following formula: R2=R1*(Uout.-Uref.)/Uref.
You should know that initially R2 should be set slightly less than the figure obtained during the calculations. In this case, you should simultaneously connect a multimeter in series to the diode to evaluate the current strength. This will avoid the occurrence of excessive current.
In this circuit, it is possible to use the same capacitors as in the previous one. But the resistors should be of better quality, especially their connections. If the contact breaks (open circuit) during operation of the installation, the LED diode will burn out due to the increased voltage.

Focusing the light flux into a beam

When creating a laser installation and using a diode removed from a DVD-RW drive, you need to understand that the emitted light will be similar to a standard LED.

LED glow

But we need a laser beam. To make it, you need to use a collimator - a special lens. With its help, the light flux will be focused into a beam. An excellent solution would be to use a lens taken from an old laser pointer in the device. By installing it using nuts and springs, it will be possible to more accurately focus the laser (its approach and distance). The lens can also be attached to the laser diode using epoxy glue or double-sided tape.
Due to the fact that it is not always possible to find a powerful diode, in this situation it is recommended to use the 808nm model.

Getting the green ray

Using a crystal of a certain color, you can produce a laser beam of green, yellow, red and blue.

Conclusion

Using a laser diode removed from a DVD-RW drive, you can create a laser installation with your own hands. Using various crystals, you can focus the beam and give it the desired color. In this case, it is necessary to take into account the peculiarities of working with such a device in order to obtain the desired result and not deteriorate your vision.

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Probably everyone has had a dream since childhood to have their own powerful laser capable of burning through steel sheets, now we can get one step closer to the dream! Sheets of steel will not be cut, but bags, paper, and plastic are easy!
For our laser, we first need a broken or not very good cutter! and DVD-RW. The higher the DVD-R recording speed, the more powerful the laser is! 16 drives contain 200 mW red lasers, as well as an IR laser, but more on that later.

Disassembling the cutter,
take out the optical part. This is what this part of the cutter looks like:

The only valuable things there are the output lens and two lasers.

Now let's get to the most important thing!

And now safety precautions for you and for the laser!

DVD-RW laser belongs to class 3B, which means it is dangerous for your eyesight! Do not point the beam at your eyes! You won’t even have time to blink your eyes before you lose your sight! a guy accidentally showed himself on one forum and ended up with several thousand scams. Consider him lucky. With a focused beam you can blind from a hundred meters away! watch where you shine!

How can you ruin an LD?
Yes, very simple! Exceed the current and it's over! and a fraction of microseconds will be enough!
This is why LDs are afraid of static electricity. Protect LD from him!
In fact, the LD does not burn out, the optical resonator inside simply collapses and the LD turns into
regular LED. the resonator collapses not from current, but from light intensity, which in its
The queue depends on the current. You also need to be careful about the temperature. when cooling the laser
Its efficiency increases and at the same current the intensity increases and can destroy the resonator! Be careful!
It can also be easily killed by transient processes that occur when turning on and off! from
they are worth protecting.

Now let's continue disassembling the drive))
We take out the laser and its radiator, and immediately solder a small one to its legs.
a non-polar capacitor of 0.1 µF and a larger polar one! so we will save
it from statics and transient processes, which LDs really don’t like!
Now it's time to think about powering our laser. The LD is powered by approximately
from 3V and consumes 200mA. A laser is not a light bulb!! never connect
it directly to the batteries! without a limiting resistor they will kill him and
2 batteries for laser pointer!! LD is a nonlinear element, so power it
You don't need voltage, but current! that is, current limiting elements are needed.
Let's look at three LD power supply schemes from the simplest to the most complex.
All circuits are powered by batteries.
1 option
current limitation by resistor. see picture

The resistance of the resistor is determined experimentally by the current through the LD.
It’s worth stopping at 200mA, further the risk of burning is greater.
although my LD worked perfectly at 300mA. any three are suitable for food
battery to the required capacity. It is also convenient to use the battery from
mobile phone (any).

Trial run

In the dark it works like a flashlight.

Focus lens

Through the lens it is possible to focus the beam, but without a rigid body the task is tedious.

Case manufacturing

Everything needs to be isolated.

Lens

By the way, this lens works better if it is turned over with the convex part facing the laser diode.

We adjust and get a more or less collected beam.

It’s probably possible to fine-tune it, but for us this was enough for the black plastic to start melting.

The match instantly ignited.

The black electrical tape was cut like a knife through butter.

This laser would make a great gun for playing toy soldiers.

Video

DVD LASER "SMOKE"

Many people make all sorts of unnecessary but cool devices, and I was no exception. I decided, following the example of many, to make a laser from a DVD - a burning diode torn out of a non-working DVD burner drive. So, we ask our radio cat to help spin up the computer:

Then we remove the drive cover and take out the strip on which the DVD laser is installed.

To connect it to the battery, you can use a specialized one with current stabilization. But these microcircuits cost $5-10, and they burn out immediately if configured incorrectly! Besides, you can’t get them everywhere.Therefore, it was decided to make our own power supply scheme, which, as it turned out, works great,also together with a 220V charger.

Battery: nickel-cadmium fingers 3 pcs or lithium-ion from a mobile phone. So let's get started, take a diode from the divider -

They say they are afraid of static, but I didn’t take any protective measures and still didn’t burn. But when the current increased above 0.3A, they flew out instantly. I burned four of them! Let's shove all this DVD laser in some suitable case, for example a Chinese lantern,

I first took the lens for focusing from the same DVD drive, but as it turned out, the laser does not work well with it - focusing is no good. I had to go to the market and spend a dollar to buy a laser pointer. Her lens is just super - it focuses to the point.

And besides, it attaches conveniently! As a bonus, we have three 1.5V button batteries, a button and a very bright red LED. In front of the flashlight, instead of glass, we put a round piece of plastic with a 10 mm hole for the beam. That's all, combat laser from DVD "smoke" is ready!

Lights matches within 1 meter, makes wood, rubber, plastic, black paper smoke well. Current consumption is up to 0.3A, but I recommend not setting the limit, but reducing it to a safe 0.2A. It will be even better if you power it from an ultra-low voltage drop - 0.05V.

For any questions write to

In the section There are vacancies for photographs of your lasers and other devices!

Diode assemblies and single matrices
Total power from 40 to 4500 W

Our company presents horizontal and vertical diode assemblies with conductive, microchannel or water cooling, operating in continuous or quasi-continuous mode.

Request specifications, photographs and prices of specific models using the button below:

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Single diode arrays

Contact us

by making a request from the site:

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Conductively cooled, high-power laser diode arrays are widely used for pumping in DPSS lasers, in medicine and aesthetics, and in laboratory research. We supply diode arrays with continuous and quasi-continuous pumping.

Possibilities:

Laser diode arrays: 20W~100W continuous pump and 85W~300W quasi-continuous pump

Available wavelengths: 795nm, 808nm, 940nm, 976nm, 1064 (+/-3nm, +/-5nm, +/-10nm)

Available housing types: CS-Mount, Narrow CS-Mount, W2

Available polarization types: TM & TE

Long service life > 10,000 hours

Vertical diode arrays, conduction cooling

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Conductively cooled high power vertical laser diode assemblies are widely used for pumping in Nd:YAG lasers to produce high pulse energy in quasi-continuous wave or pulsed mode.

Possibilities:

Power (quasi-continuous pumping): 100-300 W per die, 1~100 dies per assembly

Assembly method: vertical, horizontal, 2D

Long service life > 1 billion pulses

Available in custom housing

Diode assemblies, micro-channel cooling (MCCP)

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by making a request from the site:

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The case with micro-channel cooling (Micro-Channel Cooler Package - MCCP) is designed for high power diode matrices - up to 100 W with continuous pumping. The Micro Channel Cooler (MCC or MC2) is a highly efficient heat sink that can provide more than 1 kW of continuous pumping power from a single diode assembly. Used for heat treatment in industry - metal hardening, laser melting, cutting, welding, etc. They are also widely used in hair removal machines.

Possibilities:

Power (continuous pumping): 60-100 W per die, 1~20 matrices per assembly

Assembly method: vertical, horizontal

Pitch between dies: ~2.0 mm

Fast axis collimation optional

Long service life > 10,000 hours

Available in custom housing

Diode bars (horizontal assemblies), water cooling

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by making a request from the site:

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Water-cooled diode arrays (horizontal assemblies) are designed for side pumping in Nd:YAG lasers with simple electrical connectors and water inlet/outlet. Horizontal diode assemblies are key components for laser modules with continuous or quasi-continuous pumping, and are also widely used in repair to replace the emitter.

Possibilities:

Power (continuous pumping): 20-40 W per die, 1~20 matrices per assembly

Power (quasi-continuous pumping): 100-300 W per die, 1~20 dies per assembly

In this post I will describe how I assembled a purple laser pointer from junk I had on hand. For this I needed: a violet laser diode, a collimator to converge the light beam, driver parts, a housing for the laser, a power supply, a good soldering iron, straight hands, and the desire to create.

If you are interested and want to dig deeper into electronics, please refer to cat.

I came across a dead Blu-ray cutter. It was a shame to throw it away, but I didn’t know what could be made of it. Six months later I came across a video that showed such a homemade “toy”. This is where Blu-ray comes in handy!

The drive's read-write system uses a laser diode. In most cases it looks like this:

Or like this.

To power the “red” diode, 3-3.05 volts are needed, and from 10-15 to 1500-2500 milliamps, depending on its power.
But the “purple” diode requires as much as 4.5-4.9 volts, so powering it through a resistor from a lithium battery will not work. We'll have to make a driver.

Since I had a positive experience with the ZXSC400 chip, I chose it without hesitation. This chip is a driver for high-power LEDs. Datasheet. I didn’t bother with the wiring in the form of a transistor, diode and inductance - everything is from the datasheet.

I made a printed circuit board for the laser driver, known to many radio amateurs as LUT (Laser Ironing Technology). For this you need a laser printer. The diagram was drawn in the SprintLayout5 program and printed on film for further transfer of the drawing to textolite. You can use almost any film, as long as it doesn’t get stuck in the printer and it prints well. Film from plastic envelope folders is quite suitable.

If there is no film, no need to be upset! We borrow a women's glossy magazine from a friend or wife, cut out the most uninteresting page from it and adjust it to A4 size. Then we print.

In the photo below you can see a film with applied toner in the form of a circuit layout, and a piece of PCB prepared for transferring the toner. The next step will be preparing the PCB. It is best to take a piece twice as large as our diagram, so that it is more convenient to press it to the surface during the next step. The copper surface must be sanded and degreased.
Now you need to transfer the “drawing”. We find an iron in the closet and turn it on. While it is warming up, we place a piece of paper with the circuit on the PCB.

As soon as the iron heats up, you need to carefully iron the film through the paper.

This video shows the process very clearly.

When it “sticks” to the PCB, you can turn off the iron and move on to the next step.

After transferring the toner using a regular iron, it looks like this:

If some tracks were not transferred, or were not transferred very well, they can be corrected with a CD marker and a sharp needle. It is advisable to use a magnifying glass, the tracks are quite small, only 0.4 mm. The board is ready for etching.

We will poison with ferric chloride. 150 rubles per jar, lasts a long time.

We dilute the solution, throw our workpiece there, “stir” the board and wait for the result.

Don't forget to control the process. Carefully pull out the board with tweezers (it’s also better to buy one, this way we will save ourselves from excess mat and “snot” of solder on the future board when soldering).

Well, the board is etched!

Carefully clean it with fine sandpaper, apply flux, and tin it. This is what happens after servicing.

You can apply a little more solder to the contact pads than everywhere else, to make soldering the parts more convenient, and without applying additional solder.

We will assemble the driver according to this scheme. Please note: R1 - 18 milliOhm, not megaohm!

When soldering, it is best to use a soldering iron with a thin tip; for convenience, you can use a magnifying glass, because the parts are quite small. For this soldering, flux LTI-120 is used.

So, the board is practically soldered.

The wire is soldered in place of the 0.028 Ohm resistor, since we are unlikely to find such a resistor. You can solder 3-4 SMD jumpers in parallel (they look like resistors, but labeled 0), they have about 0.1 ohm of real resistance.

But there weren’t any, so I used regular copper wire of similar resistance. I didn’t measure it exactly - just some calculations from some online calculator.

We are testing.

The voltage is set to only 4.5 volts, so the light is not very bright.

Of course, the board looks a bit dirty before the flux is washed off. You can wash it off with simple alcohol.

Now it’s worth writing about the collimator. The fact is that the laser diode itself does not shine with a thin beam. If you turn it on without optics, it will shine like a regular LED with a divergence of 50-70 degrees. In order to create a beam, you need optics and a collimator itself.

The collimator was ordered from China. It also contains a weak red diode, but I didn’t need it. The old diode can be knocked out with a regular M6 bolt.

We unscrew the collimator, unscrew the lens and the back part, and unsolder the driver from the diode. We clamp the remaining fastener in a vice. You can knock out the diode by hitting it.
The diode is knocked out.

Now you need to press in the new purple diode.
But you can’t press the legs of the diode, and it’s inconvenient to press them in any other way.
What to do?
The back of the collimator is great for this.
We insert the new diode with its legs into the hole in the back of the cylinder, and clamp it in a vice.
Smoothly tighten the vice until the diode is completely pressed into the collimator.

So, the driver and collimator are assembled.
Now we attach the collimator to the “head” of our laser, and solder the diode to the driver outputs using wires, or directly to the driver board.

As a body, I decided to use a simple flashlight from a hardware store for a hundred rubles.
It looks like this:

All hardware for the laser and collimator.

A magnet is attached to the clothespin for easy attachment.
All that remains is to insert the laser device into the housing and tighten it.

Sprint layout 5, PCB layout files in

Laser diodes - Previously, manufacturing lasers was associated with great difficulties, since it requires a small crystal and the development of a circuit for its operation. For a simple radio amateur, such a task was impossible.

With the development of new technologies, the possibility of obtaining a laser beam in everyday conditions has become a reality. The electronics industry today produces miniature semiconductors that can generate a laser beam. Laser diodes became these semiconductors.

The increased optical power and excellent functional parameters of the semiconductor make it possible to use it in high-precision measuring devices both in production, in medicine, and in everyday life. They are the basis for writing and reading computer disks, school laser pointers, level gauges, distance meters and many other useful devices for humans.

The emergence of such a new electronic component is a revolution in the creation of electronic devices of varying complexity. High-power diodes form a beam that is used in medicine to perform various surgical operations, in particular to restore vision. The laser beam is able to quickly correct the lens of the eye.

Laser diodes are used in measuring instruments in everyday life and industry. The devices are manufactured with different power levels. A power of 8 W is enough to assemble a portable level gauge at home. This device is reliable in operation and is capable of creating a laser beam of very long length. Getting a laser beam into the eyes is very dangerous, since at a short distance the beam is capable of damaging soft tissues.

Design and principle of operation

In a simple diode, a positive voltage is applied to the anode, then we are talking about biasing the diode in the forward direction. Holes from the “p” region are injected into the “n” region of the p-n junction, and from the “n” region into the “p” region of the semiconductor. When a hole and an electron are located next to each other, they recombine and release photon energy with a certain wavelength and phonon. This process is called spontaneous emission. In LEDs it is the main source.

But under certain conditions, a hole and an electron are capable of remaining in one place for a long time (several microseconds) before recombination. If a photon with a resonance frequency passes through this area at this time, it will cause forced recombination, and a second photon will be released. Its direction, phase and polarization vector will absolutely coincide with the first photon.

The semiconductor crystal is made in the form of a thin rectangular plate. In fact, this plate plays the role of an optical waveguide in which radiation acts in a limited volume. The surface layer of the crystal is modified to form the “n” region. The bottom layer serves to create the “p” area.

The end result is a flat p-n junction of significant area. The two side ends of the crystal are polished to create parallel smooth planes that form an optical resonator. A random photon perpendicular to the planes of spontaneous emission will travel along the entire optical waveguide. In this case, before leaving outside, the photon will be reflected several times from the ends and, passing along the resonators, will create forced recombination, forming new photons with the same parameters, which will cause an increase in radiation. When the gain exceeds the loss, the creation of a laser beam will begin.

There are different types of laser diodes. The main ones are made on particularly thin layers. Their structure is capable of creating radiation only in parallel. But if the waveguide is made wide in comparison with the wavelength, then it will function in various transverse modes. Such laser diodes are called multi-house laser diodes.

The use of such lasers is justified to create increased radiation power without high-quality beam convergence. Some dispersion is allowed. This effect is used to pump other lasers, in chemical production, and laser printers. However, if a certain focusing of the beam is necessary, the waveguide must be made with a width comparable to the wavelength.

In this case, the beam width depends on the boundaries that are imposed by diffraction. Such devices are used in optical storage devices, fiber optic technology, and laser pointers. It should be noted that these lasers are not capable of supporting multiple longitudinal modes and emitting a laser beam at different wavelengths at the same time. The band gap between the energy levels of the “p” and “n” regions of the diode affects the wavelength of the beam.

The laser beam immediately diverges at the output, since the emitting component is very thin. To compensate for this phenomenon and create a thin beam, converging lenses are used. For wide multi-house lasers, cylindrical lenses are used. In the case of single-house lasers, when symmetrical lenses are used, the laser beam will have an elliptical cross-section, since the vertical divergence exceeds the beam size in the horizontal plane. A good example of this is the laser pointer.

In the considered elementary device, it is impossible to distinguish a specific wavelength, except for the wave of the optical resonator. In devices that have a material capable of amplifying the beam over a wide range of frequencies, and with several modes, action at different waves is possible.

Typically, laser diodes operate at a single wavelength, which, however, has significant instability and depends on various factors.

Varieties

The design of the diodes discussed above has an n-p structure. Such diodes have low efficiency, require significant input power, and operate only in pulse mode. They cannot work any other way, as they will quickly overheat, so they are not widely used in practice.

Double heterostructure lasers have a layer of substance with a narrow band gap. This layer is located between layers of material that has a wide bandgap. Typically, aluminum gallium arsenide and gallium arsenide are used to make a double heterostructure laser. Each of these connections with two different semiconductors is called a heterostructure.

The advantage of lasers with this special structure is that the region of holes and electrons, called the active region, is located in the middle thin layer. Consequently, many more pairs of holes and electrons will create amplification. In the region with low gain there will be few such pairs left. In addition, light will be reflected from the heterojunctions. In other words, the radiation will be entirely in the region of greatest effective gain.

Quantum well diode

By making the middle layer of the diode thinner, it begins to function as a quantum well. Therefore, electronic energy will be quantized vertically. The difference between the energy levels of quantum wells is used to produce radiation instead of a future barrier.

This is effective in controlling the beam waveform depending on the thickness of the middle layer. This type of laser is much more efficient, unlike a single-layer laser, since the density of holes and electrons is distributed more evenly.

Heterostructure laser diodes

The main feature of thin-layer lasers is that they are not able to effectively contain a beam of light. To solve this problem, two additional layers are applied on both sides of the crystal, which have a lower refractive index, unlike the central layers. This structure is similar to a light guide. It holds the beam much better. These are heterostructures with separate confinement. Most lasers were produced using this technology in the 90s.

Lasers with feedback Mainly used for fiber optic communications. To stabilize the wave at the pn junction, a transverse notch is made to create a diffraction grating. Because of this, only one wavelength is returned to the resonator and amplified. Such lasers have a constant wavelength. It is determined by the grating notch pitch. The notch changes under the influence of temperature. This laser model is the basis of telecommunication optical systems.

There are also laser diodes VСSEL and VECSEL, which are surface-emitting models with a vertical resonator. Their difference is that the model VESSEL The resonator is external, and its design is available with optical and current pumping.

Connection features

Laser diodes are used in many applications where a directed light beam is needed. The main process in assembling a device using a laser with your own hands is the correct connection.

Laser diodes differ from LED diodes in that they have a miniature crystal. Therefore, a large amount of power is concentrated in it, and therefore the amount of current, which can lead to its failure. To facilitate the operation of the laser, there are special device circuits called drivers.

Lasers require a stable power supply. However, there are models of them that have a red glow of the beam and operate normally even with an unstable network. If there is a driver, then the diode still cannot be connected directly. To do this, you additionally need a current sensor, the role of which is often played by a resistor connected between these elements.

This connection has the disadvantage that the negative pole of the power supply is not connected to the minus of the circuit. Another disadvantage is the power drop across the resistor. Therefore, before connecting the laser, you must carefully select the driver.

Types of drivers

There are two main types of drivers that can ensure normal operation of laser diodes.

Pulse driver made by analogy with a pulse voltage converter capable of increasing and decreasing this parameter. The output and input powers of such a driver are approximately equal. However, there is some heat generation, which consumes a small amount of energy.

Line driver operates according to a circuit that most often supplies more voltage to the diode than required. To reduce it, a transistor is needed to convert excess energy into heat. The driver has low efficiency, so it is not widely used.

When using linear microcircuits as stabilizers, as the input voltage decreases, the diode current will decrease.

Since lasers are powered by two types of drivers, the connection diagrams are different.

The circuit may also include a power source in the form of a battery or accumulator.

The batteries must produce 9 volts. The circuit must also have a current-limiting resistor and a laser module. Laser diodes can be found in a faulty computer disk drive.

The laser diode has 3 outputs. The middle pin is connected to the minus (plus) of the power supply. The plus connects to the right or left leg, depending on the manufacturer. To determine the correct pin to connect to, power must be applied. To do this, you can take two 1.5 V batteries and a resistance of 5 Ohms. The minus of the source is connected to the middle leg of the diode, and the plus first to the left, then to the right leg. Through such an experiment, you can see which of these legs is the “working” one. Using the same method, the diode is connected to the microcontroller.

Laser diodes can be powered by AA batteries or a cell phone battery. However, we must not forget that an additional limiting resistor of 20 ohms is required.

Connecting to a home network

To do this, it is necessary to provide auxiliary protection against high frequency surges.

The stabilizer and resistor create a block that prevents current surges. A zener diode is used to equalize the voltage. The capacitance prevents high frequency voltage surges. Proper assembly ensures stable operation of the laser.

Connection procedure

The most convenient for operation will be a red diode with a power of about 200 mW. Such laser diodes are installed on computer disk drives.

• Before connecting using a battery, check the operation of the laser diode.
• You need to choose the brightest semiconductor. If the diode is taken from a computer disk drive, then it emits infrared light. The laser beam must not be pointed at the eyes, as this will cause eye damage.
• The diode is mounted on a radiator for cooling, in the form of an aluminum plate. To do this, pre-drill a hole.
• Apply thermal paste between the diode and the radiator.
• Connect a 20 Ohm and 5 watt resistor according to the circuit with batteries and a laser.
• Bypass the diode with a ceramic capacitor of any capacity.
• Turn the diode away from you and check its operation by connecting the power. A red beam should appear.

When connecting, be aware of safety. All connections must be of high quality.