Results 1 to 5 of 5

Thread: Strange violet laser modules

  1. #1
    Join Date
    Sep 2013
    Location
    Johannesburg, South Africa
    Posts
    7

    Default Strange violet laser modules

    Hi All,

    I located two very strange violet laser modules that I could not pass up. (I acknowledge I have an addiction)

    They are class III and listed as 395 to 415 nm. They look identical except one has a rating of 30mW and the other is 60mW.

    They are housed in massive cylindrical modules 98 mm in diameter (~4 inches). Half of it is an Aluminium extrusion with a central core (30mm) for the lens arrangement and space for a PCB with cooling fins. The aluminium part is 152 mm long and the one end has a stainless steel cover making the whole unit 256mm long. Input is from a single DB-25 connector that has most of the pins connected.

    Inside are two small stepper motors. One drives a carousel with 6 10mm diameter glass filters. They look like a increasing series of neutral density filters with one pretty clear and the last one not as dark as a welding glass. The other stepper is a linear output unit that moves an optical component linearly in the beam axis, forward and back by about 15 mm (spring return) near the laser end. This optical component seems to be a faintly astigmatic element. The output lens has a aperture of about 12mm with an approximately 25mm lens. The focal length of the exit lens is about 100mm.

    The laser itself is mounted onto a solid block of aluminium about 26x28x35mm that is clamped to the main housing extrusion with what looks like a toroidal Peltier cooler device sandwiched in between. It has on the one side a funny little turret with screws that may be used to align internal optics. The 10 conductor flat cable going to the laser PCB also supports another small PCB with a thermistor that measures the block temperature. The Peltier device is plugged into the main PCB though. The exit of the laser bock has a 9mm lens with a ~4mm aperture behind it.

    The main PCB has about 23 ICs, some of the interesting looking ones below.

    MB90F574A (main processor looking guy)
    LTC1435ACG (DC-DC converter)
    MAX202ECWE (communications?)
    L6219DS (stepper drivers x 2)

    The incoming DB-25 connector has E-OPTIC410 on a small label
    The laser flat cable says E-LASER-MODUL
    They may have some connection to Heidelberg (or other) printing presses but not sure. Perhaps a plate burner or photo setting machine. See answer below.

    Now the question is, should I post some internal pictures for you curious people?
    Could I use them in a galvanometer stereo-lithography 3D printer?
    Should I try and sell them?
    How could they be tested (there are no exposed connections to the laser diode) and repaired (likely broken in some way)?

    PS.
    Searching has found the following that may be the source of these units. Looks like Heidelberg make 30 and 60mW violet laser plate setters that are switchable to 5mW for sensitive plates or film. Looks like they are worth US$1000 as a trade in. Eventually some of these machines will wind up on the surplus market, worth keeping an eye out if looking for 60mW violet in a jumbo housing.

    I am guessing they are digitally modulated at full power and the attenuator carousel is used to select the output power for various plate and film sensitivities.
    The machine resolution can be selected from 2032 to 3386 dpi so I expect the moveable lens is used to set the spot size or optimise the beam in some way.
    My calculations suggest that some of the units can expose at a pixel frequency of 36 million pixels per second. This is pretty good for a violet laser I think.


    http://www.us.heidelberg.com/www/htm..._violet_plates
    http://bob-weber.com/detail.aspx?e=1872
    http://www.bob-weber.com/downloads/p...Heidelberg.pdf

    Kalle
    --
    Johannesburg, South Africa
    Last edited by KalleP; 10-05-2013 at 09:08. Reason: added some calculated results
    Kalle
    --
    Johannesburg, South Africa

  2. #2
    Join Date
    Sep 2013
    Location
    Johannesburg, South Africa
    Posts
    7

    Default

    An optical question..

    Typically how much more power does the IR pump laser have compared to the output beam in these small, frequency doubling and tripling green, blue, violet lasers?

    Kalle
    --
    Johannesburg, South Africa
    Kalle
    --
    Johannesburg, South Africa

  3. #3
    Join Date
    Apr 2012
    Location
    Beaverton, OR
    Posts
    239

    Default

    Consider my 355nm DPSS laser, 120w of IR diodes gets about 6 watts average power out in UV.

  4. #4
    Join Date
    Oct 2007
    Location
    Vancouver, Canada
    Posts
    326

    Default

    Are you sure these aren't just a 405nm diode based module ?

  5. #5
    Join Date
    Sep 2013
    Location
    Johannesburg, South Africa
    Posts
    7

    Default

    Don't know, I thought all violet lasers were multipliers, shows that I am a bit out of touch.

    I tried to upload two pictures but the browser window went grey and unresponsive. Is there something special I should do with FireFox?
    Tried again, this time I got an upload window, for the url's below it gives invalid URL and for local file browse there is not OK button when that tab is open.

    http://www.letterpress.co.za/images/violet%201.jpg
    http://www.letterpress.co.za/images/violet%202.jpg

    There are two photos (violet 1 and violet 2), one of the links styles above should work I hope.
    Last edited by KalleP; 01-13-2014 at 07:58. Reason: Add links for images
    Kalle
    --
    Johannesburg, South Africa

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •