new Laser

Kiffdino · Post by **Kiffdino** » Mon Mar 12, 2007 10:27 pm

nice !

untill now Beginning Holography seems to be my private knowledge base.

well i want to get myself a new laser, because i want to do brighter holograms with transmission holography.

the integraf 5mW laser is not enough

my budget is limited

so I thaught i get the used 10mW hene laser from meredith.

do u think that is a good buy ?

or should i wait until integraf has their 50 mW laser diode in stock?

Tony · Post by **Tony** » Mon Mar 12, 2007 11:11 pm

I'm a strong HeNe fan, as the power available at cost is quite good, and they avoid problems of mode hopping, etc.

If you look around you should be able to get them at reasonable cost - 10$/mW or less, not including the power supply.

You should try to get the highest power you can - Nothing makes holography easy like having plenty of photons!

So far, no one has found a diode laser above 50mW that is stable and reliable enough. We're still waiting to see if the Integraf diode can work well.

dave battin · Post by **dave battin** » Mon Mar 12, 2007 11:49 pm

yes a hene is probably your best bet for the dollar ,i've always had good luck with the big"E" bay. just be sure to insure it for what you paid and i use paypal (this gives you a safety if the seller is a flake), lets see what we can find ..........

Colin Kaminski · Post by **Colin Kaminski** » Tue Mar 13, 2007 12:07 am

I got a note from Alec at integraf saying they are hoping for the laser to be available this spring. If you want more than 5mw now a HeNe is your best option.

Kiffdino · Post by **Kiffdino** » Tue Mar 13, 2007 2:06 pm

what you think about this one

Is it a risk?

its a 35mW HeNe laser from Ebay:

http://cgi.ebay.de/ws/eBayISAPI.dll?Vie ... 46113&rd=1

which a could combine with this alden powersupply from Meredith:

http://www.mi-lasers.com/cgi-bin/shoppe ... esult.html

this deal sounds almost to good to be true.

im very sceptical.

Tony · Post by **Tony** » Tue Mar 13, 2007 3:13 pm

I have one of the Sunnking lasers 1145-3494P. Although these have a CDRH max rating of 35mW on the label, they typically only make around 20mW. This is customary labelling for HeNes.

Still, at 20mW, it would be a good laser for holography.

Joe Farina · Post by **Joe Farina** » Tue Mar 13, 2007 4:28 pm

Looks like you're on the right track, I would definitely go with a HeNe. Ebay deals are always something of a risk, those particular lasers are apparently untested by the seller, so you don't know what the output will be until you actually test it yourself. It seems like the MALE portion of the Alden connector has been cut off the wires coming from the head, at least that's the impression I got. At first glance, the power supplies from Meredith look good, but apparently it only has the female end of the Alden connector, which is typical. I recently bought a complete Alden connector (both male and female) from Sam Goldwasser at a reasonable price; otherwise, they seem pretty hard to find. The power supply of my back-up HeNe, a 107B, failed due to a poor connection within a corroded Alden connector.

Kiffdino · Post by **Kiffdino** » Tue Mar 13, 2007 6:47 pm

ok let me get this right

an alden connector has a male and a female side.

The powersupply from Meredith has only the female-connector side.

The male-connector from the Sunnking laser has been cut of.

As far as I can tell from the picture of the powersupply at meredith,

there is only one red and one black wire going inside the alden connector.

why not cut of the female connector from the powersupply.

Then join the red and black wires coming from the laserhead

directly to the ones from the powersupply using a simple insulated screw join ?

couldnt be that difficult...

ErichRose · Post by **ErichRose** » Tue Mar 13, 2007 8:02 pm

Oh my gosh! be real careful...

Those connectors are used for a reason. Or probably many reasons but the one I am aware of most is the fact that the possibility of sparking across the two is pretty high*. That big plastic connector is designed to fully enclose and deeply bury the connections. Some things should not be just rigged up. Spend a few more dollars and get the proper connector.

* I took a shot from a HeNe power supply many years ago. I never touched a thing. The spark jumped an inch or more from the anode(?) wire hitting the rubber handled X-acto knife I was holding. It passed into my hand despite the rubber insulation and out my thigh where it was pressed against the metal drafting table I was sitting at. It caused a massive muscle spasm and the next thing I remembered was me and the rolling chair bouncing off the wall behind me. It took a while to find the knife. It went flying. It only hurt where my thigh had touched the table but there were other effects. My senses were crystal clear for almost two days (kinda cool really), but I couldn't concentrate on a thing. I mean I had trouble completing a sentence. It was real problem being that I am a designer and was in need of all my problem solving skills for the project.

Again, it isn't low voltage electronics and it isn't household current. It's something more and requires real care. You are not just wiring up a fancy light bulb.

Kiffdino · Post by **Kiffdino** » Tue Mar 13, 2007 8:40 pm

wow,

ok ill be carful

but still, as described in that Ebay offer, the wire coming from the laser was cut off.

So i would need to connect the male alden connector to the cut wires coming from the laser head.

Anyway I would have one weak connection.

How about that.

Last year i was connecting two high voltage wires in my garden.

The connection had to withstand rain.

So I used a special container.

Inside you put both ends of the wires connect them and then fill the container with epoxy.

Thats very safe.

like one of these, sorry its in german, just look at the picture:

http://business.lieske-elektronik.de/ar ... .htm?pid=1