well I wouldn't know what drive would be the best for it but you're best bet would be to try find a manufacturer with an office somewhere you could actually visit if it was needed. I'd start with whoever I could find closest to me and contact them first via email and work my way out.
Tech companies generally respond well to requests like this as there's quite a bit of free publicity involved for them as well as appearing to help students research or you could go completely homemade with a variation of the technique here: teravolt.org/Laser_Microscope.htm
I understand why you decided to use the ps3 BDVD then, if you was trying for top marks because you would deserve it, if you cracked the drive and fabricated a biometric unit out of it. I remember some question in a computer online train coarse, about retina scanners, and finger print scanning using biometrics, and I never really needed to know how they worked or what lasers they us, until now. So if I'm right, is this something your trying to make?
I was thinking, even if you find the right housing and laser with a card you can download data from, you will still need a fuzzy-logic controller, connected separately to the control of the laser, because I believe you maybe able to read from the card, but not
send commands to it to control the laser movements, I dunno?
And you said something about a bigger connector, what about a old SCSI printer cable? Its screened and has a 50 way centronic at one end, maybe just what you looking for.
Sorry I should of explained the purpose
My intention is to measure the 2D surface profile of a polished metal surface. I hope to profile the micro peaks and valleys of the surface.
I would imagine the motor should be easy enough to hack onto to control the movement.