On Oct 14, 11:32*am, "Arfa Daily" wrote:
"Nick Fielding" wrote in message

...





On Oct 14, 8:48 am, "Arfa Daily" wrote:
"Nick Fielding" wrote in message

....

Hello,

I'm trying to figure out how to replace a laser diode inside a ps3 blu-
ray drive. I think I now know the best way to extract the diode.

My problem is installing the new diode; I have read in several places
that it's not simply a case of whacking the new one in, it has to be
aligned? Is this true, and if so, what would be the best way to go
about aligning it? How much is it likely to have to be rotated, i.e.
fractions of a degree or larger? I don't see that it can be rotated
that much as its degree of rotation would be limited by the flex cable
it's soldered to.

Many thanks for any help!
Nick

I've got a colleague who replaces many PS3 laser assemblies (I take it
you
are referring to the optical head which runs on the deck within the
drive,
not the *actual* laser diode ?) I will ask him what is necessary. Note
also
that I think I recall him saying that there are two if not three
different
variants, so make sure you get the right one. I have dismantled a number
of
these drives to remove discs from PS3s suffering the YLOD condition. Be
careful when you replace the drive's top plate, as several bits of disc
handling mech, have to engage correctly with other bits on the main body
of
the drive. Note also that once the top cover is removed, exposing the top
mech plate of the drive, the disc clamp just lifts away. It is not
retained
by anything other than being 'sandwiched' between the mech plate and the
cover. When reassembling, it just sits on top of the (should be at that
point closed) lifter 'scissors'.

Arfa

Hi Arfa,

Thankyou for taking the time to reply but it's the laser diode itself
I'm working on replacing. I can replace the laser assembly no problem,
however, it's not at all economical given the price of a laser
assembly so am trying to see if I can refurbish broken assemblies by
replacing the laser diode.

Thanks,
Nick

In that case, I think you will really struggle to ever get it working again.
The laser diode is an *extremely* precision fit in the optics, aligned at
the factory in a precision jig. *I once experimented with this on CD lasers,
with just about zero success. Even if I got it to read again, the
playability was poor. Ask anyone who has ever replaced a Pioneer laser just
how difficult it is to align the diffraction grating. Gnat's bollock
precision doesn't begin to describe how difficult it is to get it right, and
that's Grand Canyon versus an alleyway in terms of relative data pit size..

Given that CD optics are 'broken leg' technology, then DVD optics are in
'heart transplant' territory. Blu Ray, as PS3 lasers are, then fall into
'brain surgery' by comparison ... *If the laser diode is even a vanishingly
tiny amount off-axis, the beams will not pass through the centre of the
lens, so the chances of them being reflected back from the disc correctly to
hit the pickup diodes are, IMHO, poor at best. Bear in mind also, that it is
not necessarily the laser diode that is at fault. Problems with laser
assemblies can also be down to contaminated optics - i.e. nicotine on the
critical angle mirror - a faulty pickup diode assembly, or faulty tracking /
focus coils.

I am surprised that you think that the cost of a replacement optical
assembly warrants attempting to do it by this method. According to my oppo,
the price of replacement optical heads is quite reasonable, and allows a
good margin on the job ...

You might like to look at Sam's stuff on these heads at

http://www.repairfaq.org/sam/Blu-ray/site1/optics.html

and also the material at

http://www.optoiq.com/index/photonic...ications/lfw-d...

which will give you a bit more of an insight into how much precision is
involved in these assemblies.

Arfa- Hide quoted text -

- Show quoted text -


That does indeed look like it requires a lot of precision.

A lens assembly costs upwards of £25 whereas a replacement laser diode
for the 410aca blu-ray drive I can get for £7. Obviously replacing the
laser diode is a fiddly and by the looks of it impossible job;
although there are people out there who are managing to do it, maybe
they have their own jig or something.

I'll probably give it a go and fail.

Many Thanks,
Nick