How to adjust the laser head voltage? The voltage of the laser head of the CD player is several V

1. Clean the laser head: If you are afraid of breaking it, then only clean the bald head objective. Take out the optical drive, open the box, find a small round lens, dip a cotton swab in a little pure water, wipe the objective lens again, and wait for the water to dry completely before loading it back into the test machine.

If you have strong hands-on ability, you can remove the bald head assembly, soak it in a basin filled with purified water (with a little dishwashing soap), pinch the corners (non-bald objective lens and circuit part) with your hands, rinse back and forth constantly, take it out after a few minutes and rinse it with clean water, spin it dry and then dry it and put it back into the test machine. If it doesn't work, then:

2. Adjust the emission power of the laser head: see if there is an adjustable resistance on the circuit board of the bald head assembly, it is best to remember the initial resistance value under the monitoring of the multimeter, and then adjust it to make the resistance smaller (the adjustable resistance is a 3-pin element, but the one used on the bald head is generally only used to 2 pins, that is, the adjustable end and the other pin are connected), install it back and try the machine again.

Yes, this brother has the same hobby as me

Disassemble the optical drive

In the laser head group, there's a miniature adjustable resistor next to it, take a screwdriver and turn it left or right

Until you find out that the laser intensity is stronger, it's fine

Disassemble the optical drive, there is a small potentiometer on the side of the bald head, and use a small Phillips screwdriver to twist it slightly in the counterclockwise direction.

Adjusting the voltage of the laser head is a last resort, and it will not help if the semiconductor laser is aging.

It is a high-tech operation, and it is recommended that you find a master to help you.

The upstairs brother (Da Li Dart) is engaged in home appliance maintenance, right? It's very professional.

The laser head voltage of the CD machine is positive 5V and positive 12V voltage.

Sometimes this phenomenon happens, and in the past, normal discs were used, but now some discs are not "recognized". This is a problem that almost all of you will encounter after a year or two of use with an optical drive. In addition to ruling out the cause of disc damage, it is possible that dust has accumulated on the lens of the laser head assembly.

You can use the cleaning tray to clean it once or twice to see if it improves. If it is ineffective, it is usually caused by the aging of the laser head (the power of the laser transmitter is weakened or the sensitivity of the receiver tube is reduced). Someone with experience in electrical repair can help you open the casing of the optical drive and find a chip trimmer potentiometer on the laser head assembly.

This potentiometer is very small, can rotate 360°, there is no limit, and adjusting it can change the emission power of the laser emitting tube. Some optical drives adjust clockwise to increase power, while others do the opposite. The user can first fine-tune about 5° in a certain direction, and then test the effect of the disk recognition, if it is greatly improved, it proves that the adjustment is in the correct direction.

If the recognition rate is worse or even not, the potentiometer will be restored and then fine-tuned in the opposite direction by about 5°, which is generally effective. However, special attention should be paid to the fact that the angle of adjustment should not be too large, otherwise the laser power will increase too much, which will make the laser hair heat serious and sharp aging, or even failure.

Why do people who don't know much always like to adjust the power potentiometer? I never tune it because it will only make it bad faster and it won't have any effect yet.

View the original post

1. If you want to increase the optical power of the laser head, you need to adjust it by increasing the voltage and current, it should be noted that the power of the optical drive laser head itself is rated, but by changing the voltage and current, the optical output power of the overclocked laser is overclocked;

2. Even if you plan to overclock the laser power, you must control the voltage, and the power of the optical drive will be reduced after one or two years of use.

Only the output voltage can be measured, and the oscilloscope cannot measure the power directly.

It can be equipped with a photoelectric probe to convert the optical signal into an electrical signal, but there is no way to judge the actual and accurate power, only the change of the laser energy.

Use a clean cotton swab, dip a little alcohol (preferably anhydrous alcohol), gently wipe the surface of the laser head, and wait for the alcohol to evaporate. As shown in the figure below:

Take a cotton ball and dip it in some alcohol, not too much, just wipe it a few times.

A constant current source of 10 mA will do.

It is not enough to have a voltage alone, it is necessary to have a servo circuit.

Laser welding can be found in Aachen United Technology (Tianjin)****, transparent, thoughtful service, is your rest assured choice! Aachen United Technology (Tianjin) was established in 2018, the company's core business areas: advanced laser manufacturing technology and equipment research and development and introduction, process development and product processing, technical consultation and training, including laser cladding, laser additive manufacturing, laser repair, laser welding, laser micro-nano processing, etc., welcome to call for consultation!