Photodiode / Laser pulse measuring test set up.

[VDX]

... for sensing and adjusting IR-lasers I'm using "indicator cards" - here's a common type: https://www.conrad.de/de/ir-indikato...omSuggest=true

Or special coated ceramic plates for high power lasers, as this plastic cards can only withstand some hundred Milliwatts ...

Viktor

[TCWilliamson]

... for sensing and adjusting IR-lasers I'm using "indicator cards" - here's a common type: https://www.conrad.de/de/ir-indikato...omSuggest=true

Or special coated ceramic plates for high power lasers, as this plastic cards can only withstand some hundred Milliwatts ...

Viktor

Oh cool, that's pretty neat.

The IR Laser Diode that you linked to only outputs 10mW.
You should not have any problems with damaging the photo
diode that you linked to.

As Dan has mentioned it would be a lot easier to align a
Laser beam or dot if you could see it.
Don't forget that the Photo diode output is not linear and
outputs different voltages/currents at different wavelength
even if those input wavelengths are the same identical
power.

Not sure what part of the Globe you are on but if Canada
is closer than the UK I can sent you a couple of 650nm
red Lasers for your experiments.


Jerry

As it happens I am in the uk!

Thanks for the offer however. I really appreciate it.

[buffo]

As it happens I am in the uk!

Slightly off-topic, but if you edit your user profile you can put your location in. This will help people out, since they'll know if you are close to them. (You can be as specific or as general as you want, but even "UK" is better than nothing.)

Just a suggestion!

Adam

[TCWilliamson]

Slightly off-topic, but if you edit your user profile you can put your location in. This will help people out, since they'll know if you are close to them. (You can be as specific or as general as you want, but even "UK" is better than nothing.)

Just a suggestion!

Adam

Good point. I shall do that.

Photodiodes arrives along with a pack of 'lab snacks'! Seems I need to move into the optics industry if this is the treatment you get from suppliers....

for the Photodiode circuit. Should I just go with the standard layout as shown in their page?

[planters]

Thorlabs is the only major supplier that does this. My son (who sells computer components) imitated this perk and was surprised at the initial confusion it caused followed by the appreciation from repeat customers. He considered expanding into cigarettes, porn... never mind. Steve can give a few good stories about the feeding frenzy this can cause, however.

Your plan regarding the big laser is good. Not only will you be much safer when dealing with it after acquiring some experience, but what is the point of working with it if the nuances of its operation are black box? For example, I have a fast photodiode that when hooked up to a very fast GHz oscilloscope (borrowed), displays the extremely high speed mode modulation (sub nsec) WITHIN each Q switched pulse in a laser similar to yours. I doubt many (no, not all) of the owners of these lasers were aware of presence of these effects. I wasn't and that is the joy of discovery that you will experience if you wait.

[TCWilliamson]

Thorlabs is the only major supplier that does this. My son (who sells computer components) imitated this perk and was surprised at the initial confusion it caused followed by the appreciation from repeat customers. He considered expanding into cigarettes, porn... never mind. Steve can give a few good stories about the feeding frenzy this can cause, however.

Yes. I was suggesting to my colleages we should do the same thing, some customer bribery!...
Feeding Frenzy?

Your plan regarding the big laser is good. Not only will you be much safer when dealing with it after acquiring some experience, but what is the point of working with it if the nuances of its operation are black box? For example, I have a fast photodiode that when hooked up to a very fast GHz oscilloscope (borrowed), displays the extremely high speed mode modulation (sub nsec) WITHIN each Q switched pulse in a laser similar to yours. I doubt many (no, not all) of the owners of these lasers were aware of presence of these effects. I wasn't and that is the joy of discovery that you will experience if you wait.

Interesting...



I've just been looking at the datasheets and information.
https://www.thorlabs.de/thorproduct....tnumber=FDS010

It recommends 10V and a 50R here:
http://puu.sh/qovu5/c3694458bf.png

using the drawing here:
https://www.thorlabs.de/images/TabIm..._DWG_1_780.jpg

The Datasheet says:
Max Current = 5mA
Responsivity at Peak 0.44 A/W

(I assume A = amps and W = watts?)

So the max optical power I can put into the photodiode is:
0.005/0.44 = 11mW

Is this correct?
I figured I'd rather double check then double pay at £31 + £10 shipping a pop.

[mixedgas]

Feeding Frenzy at CWRU... A few years ago...In the lab from before time began...(literally next door to Michelson and Morley's lab...)
Steve works with grad students.
Steve gets a Thorlabs box..
Three students sign for the box and set it on my desk, patiently waiting for me....
Steve carefully opens box removes optics and paperwork, sets red box on desk and steps back.
Let the battle for yummieness begin.
I kid you not, I used to work in a lab where I needed 2-3 Thorlabs orders a week for four months...
And remember many grad students make 25-30K a year and work 50-60 hour weeks..
!
I have seen students divert an order from Newport to T-Labs... For one and only one reason.. Thorlabs used to ship a coffee mug with the box with large orders, and big orders get big/multiple labsnax boxes.
!
My former boss, who personally did 16 million dollars in Optics and Lab laser sales a year, called that the most brilliant technical marketing move he's ever seen. Better then the nice but free customized laser hazard signs that Coherent used to make. We handed out tape measures, and at conferences, grad students would line up for our free tape measures and wavelength/wavenumber conversion charts. I'd fly into a conference with -2-3 cases of custom tape measures. That would be gone in 5-10 minutes. Ok not as good as Coherent "Danger Laser" window hangers in Klingon, but still pretty good...
!
I've been to labs where success is measured by big Champaign bottles on book shelves for every paper published and every student who graduates,, but the most telling labs are the ones who put up a labsnax box for every paper published. Saw one that added extra shelves around the top of the ceiling for that.
!
Other day last week, I had a sad, tired, Indonesian student who was working 12 hours at a microscope (170,000$ laser confocal microscope) and skipped breakfast and lunch. Even knowing that it was not Halal food, I went to my office and quietly returned with a fresh labsnax box. I left it by her stuff and left the room. Four hours later I return to check on her... BIG SMILE, Made New Friend, Thorlabs made a new future customer, and she did much better work with higher blood sugar.
!
Displayed Labsnax boxes are a sign that you have funding, are technically skilled, own a big optics lab, or are at least smart enough to reuse the handy sized red box to store parts.
!
"Face Value" should run for president...
!
Steve

[TCWilliamson]

Feeding Frenzy at CWRU... A few years ago...In the lab from before time began...(literally next door to Michelson and Morley's lab...)
Steve works with grad students.
Steve gets a Thorlabs box..
Three students sign for the box and set it on my desk, patiently waiting for me....
Steve carefully opens box removes optics and paperwork, sets red box on desk and steps back.
Let the battle for yummieness begin.
I kid you not, I used to work in a lab where I needed 2-3 Thorlabs orders a week for four months...
And remember many grad students make 25-30K a year and work 50-60 hour weeks..
!
I have seen students divert an order from Newport to T-Labs... For one and only one reason.. Thorlabs used to ship a coffee mug with the box with large orders, and big orders get big/multiple labsnax boxes.
!
My former boss, who personally did 16 million dollars in Optics and Lab laser sales a year, called that the most brilliant technical marketing move he's ever seen. Better then the nice but free customized laser hazard signs that Coherent used to make. We handed out tape measures, and at conferences, grad students would line up for our free tape measures and wavelength/wavenumber conversion charts. I'd fly into a conference with -2-3 cases of custom tape measures. That would be gone in 5-10 minutes. Ok not as good as Coherent "Danger Laser" window hangers in Klingon, but still pretty good...
!
I've been to labs where success is measured by big Champaign bottles on book shelves for every paper published and every student who graduates,, but the most telling labs are the ones who put up a labsnax box for every paper published. Saw one that added extra shelves around the top of the ceiling for that.
!
Other day last week, I had a sad, tired, Indonesian student who was working 12 hours at a microscope (170,000$ laser confocal microscope) and skipped breakfast and lunch. Even knowing that it was not Halal food, I went to my office and quietly returned with a fresh labsnax box. I left it by her stuff and left the room. Four hours later I return to check on her... BIG SMILE, Made New Friend, Thorlabs made a new future customer, and she did much better work with higher blood sugar.
!
Displayed Labsnax boxes are a sign that you have funding, are technically skilled, own a big optics lab, or are at least smart enough to reuse the handy sized red box to store parts.
!
"Face Value" should run for president...
!
Steve

Great story!

I'm going to have to propose this to our boss tomorrow! I think it could work quite well possibly...


Any thoughts on my photo-dilemma?

[danielbriggs]

@Steve...
I have no shame!

[White-Light]

Thorlabs is the only major supplier that does this. My son (who sells computer components) imitated this perk and was surprised at the initial confusion it caused followed by the appreciation from repeat customers. He considered expanding into cigarettes, porn... never mind. Steve can give a few good stories about the feeding frenzy this can cause, however.

I know of a computer component supplier that does this along with a contact lens supplier. Both supply a small bag of Haribo tangfastics with every order. Can't say it makes me buy any more goods, but I certainly look forward to them arriving! Probably good for customer loyalty though.

Just in case you don't have them outside the UK: