flashing for laser power ?

[vlad777]

Can I edit and flush DVD firmware to increase laser power?
Or do I have to do some hardware modification?

I have a few DVD recorders and readers that partialy work.
Sometimes when I increase the laser current by adjusting
the pot on the head it starts reading but the problem
is that this only increases for 2-3 mA (as I measure)
and the total current is 87 mA (when reading).
I would like to increase for 10-15 mA or maybe more
just to see will it start reading.

Also I am interested what actualy gets weared out here
the laser or the sensor.If it is the laser then I can
increase laser power withot fear that it will burn the cd/dvd.
Because light intensity then just gets restored to the old value.

Thanks.

 

[dknguyen]

THe laser's lifetime is shortened if you increase the power. Increasing the power by 20% sounds like it would burn out to me. Laser diodes are very finicky.

It takes a precise current to get the proper lazing action, too low or too high and it doesn't work...and kills of of course. You'd have to get some pretty precise data about the laser diodes being used.

 

[Boncuk]

Laser power

Hello vlad777,

having already played around with your laser you will have noticed that there is no monitoring diode in the circuit.

CD-ROMs and writers usually omit the monitor diode. For that reason the lasers are overpowerd on delivery.

Overpowering a laser reduces its lifetime to approximately 100 hours of operation.

Increasing the forward laser current will just give you the chance to burn one more CD. After that the laser will be completely worn out.

As a result you are forced to purchase a new device, and that's what the industry expects of you.

Boncuk

 

[blueroomelectronics]

The question is why? What would it accomplish?

 

[vlad777]

This is read current.I imagine that writing current is much higher
so I guess that laser can take the inc I mentioned when it
comes to reading.

I hope to accomplish fixing it.