B&W-tech Spectrometer & 473 module: Setup+Mods+Info

[CynicalBrad]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Only price I was able to find publicly listed for that software was $500. Might need to send an email to bw-tek and see if their price is lower.

 

[paul1598419]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

I'm sure it is. The Ocean Optics software is ~$250.00. I think it is better than the BWSpec.

 

[CynicalBrad]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Look at a company called I believe science surplus. They sell these spectros aligned for $500 or as a kit unaligned for $200 with their own software which looks a lot better than what we currently have.

 

[paul1598419]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

I already looked at them last night as part of my investigation into the power supply for these. They have their own software that somebody in that company wrote. It can't be any worse than what we have now, but I doubt it is nearly as good as the OEM software. In fact, I'm sure it isn't. The cheapest we could get it is for the price of an unaligned version of their specrto, which isn't as good as these probably are. I looked at their specs for all their products and was not impressed.

 

[Mosc007]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Mine arrived today. This is the complete unit mounted in the Aluminium housing. I have only done a quick test at work.

It was $50 US + $53 US for postage to Australia.


After bypassing the Keyswitch and turning it on I have a nice Blue beam from it. It's quite bright until the laser stabalises. After about 1 min the output is probably 0.5 mW as advertised. It certainly is much brighter before it stabalises. The Stability LED goes out when it's stable.

The Beam is not well collimated out of the device that has the Fibre frorm the laser an the Fibre from the Spectrometer.

I can't test the Spectrometer at work as I dont have a serial cable. I suspect it is probably functional.

I will do some more testing when I get home form work tonight.

 

[Mosc007]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

The spectrometer is the main reason I bought it. The 473nm is a nice addition to my collection though. The seller did say the baffles will need removing from the spectrometer.

I have many years experience with com's programming in VB6. If I am not happy with the software provided I can write my own. It's easy enough to log the com's on the supplied software to work out the protocol and data format. At worst the spectrometer can be put into ascii mode which looks very simple to work with. There is some information supplied in the pdf files supplied with the software.

 

[diachi]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Mine arrived today. This is the complete unit mounted in the Aluminium housing. I have only done a quick test at work.

It was $50 US + $53 US for postage to Australia.


After bypassing the Keyswitch and turning it on I have a nice Blue beam from it. It's quite bright until the laser stabalises. After about 1 min the output is probably 0.5 mW as advertised. It certainly is much brighter before it stabalises. The Stability LED goes out when it's stable.

The Beam is not well collimated out of the device that has the Fibre frorm the laser an the Fibre from the Spectrometer.

I can't test the Spectrometer at work as I dont have a serial cable. I suspect it is probably functional.

I will do some more testing when I get home form work tonight.

Has anyone tried removing the PD on this batch of units yet? Usually that'll bring the power up on these. Sounds promising seeing as yours was doing higher power and then apparently tuned itself down.

As for the beam, you either need a fiber collimator or you need to remove the fiber/fiber launch and install a collimator somewhere on/in the head.

I'm hoping the raw beam out of these is nicer than the version with no pump correction, it should be.

 

[Mosc007]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Got around to having a play with the Spectro.

The Seller was correct. There were two baffles installed inside it giving it a very narrow bandwidth. Very easily removed. Sorry, I forgot to take a pic of the Spectro opened up.

The Combiner for the two Fibres is something I don't know about. The Spectro measures the beam at 610 nm. Even thought its 473nm. There must be some 610nm in the output beam from the laser. It's split in the combiner and the 473nm is passed to the output.

I did some tests on the accuracy of the Spectro. It's not bad. considering it's been bounced around with very poor packaging from the US to Australia.

It's about 10nm out of calibration accross the ranges I tested. I have included the images of the Spectro software running.

Wavelengths tested were,

473 nm From this laser.
505 nm from my Sharp 505 Pointer.
532 nm from a 30 mW Pointer
650 nm from a 0.5 mW Pointer. Ambient noise on this due to low signal level.

Pics of both sides of the Unit as well as a beam shot. Done with a Phone so the beam spot is very saturated.

 

[diachi]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Got around to having a play with the Spectro.

The Seller was correct. There were two baffles installed inside it giving it a very narrow bandwidth. Very easily removed. Sorry, I forgot to take a pic of the Spectro opened up.

The Combiner for the two Fibres is something I don't know about. The Spectro measures the beam at 610 nm. Even thought its 473nm. There must be some 610nm in the output beam from the laser. It's split in the combiner and the 473nm is passed to the output.

I did some tests on the accuracy of the Spectro. It's not bad. considering it's been bounced around with very poor packaging from the US to Australia.

It's about 10nm out of calibration accross the ranges I tested. I have included the images of the Spectro software running.

Wavelengths tested were,

473 nm From this laser.
505 nm from my Sharp 505 Pointer.
532 nm from a 30 mW Pointer
650 nm from a 0.5 mW Pointer. Ambient noise on this due to low signal level.

Pics of both sides of the Unit as well as a beam shot. Done with a Phone so the beam spot is very saturated.

There's nothing in a 473 DPSS that'd produce ~610nm. The only wavelengths present should be ~808nm, 946nm and 473nm. Perhaps that reading is a result of fluorescence somewhere? Or some other source?

10nm out isn't bad (for the price at least), now we just need software that allows us to adjust the calibration!

Is that output beam you posted a picture of coming from the fiber?

Thanks for posting your results!

Hoping mine shows up this week...

 

[Mosc007]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

There's nothing in a 473 DPSS that'd produce ~610nm. The only wavelengths present should be ~808nm, 946nm and 473nm. Perhaps that reading is a result of fluorescence somewhere? Or some other source?

10nm out isn't bad (for the price at least), now we just need software that allows us to adjust the calibration!

Is that output beam you posted a picture of coming from the fiber?

Thanks for posting your results!

Hoping mine shows up this week...

That 610 is odd. Thats with both fibres plugged into the combiner, or what ever it realy is. Maybe it has something inside it causing the frequency shift. The spectro reading of the 473 is shining both fibres together. Doing it thay way only 473 was present.

That beam shot is from the output module. I can do another from the fibre output.

The beam is strange. Maybe its how fibres work. Letting the beam expand to a few inches its not just a large circular dot. Its made up of hundreds of tiny dots. I can probably get a shot of that.

Its late here and i didnt have much time to test it.

I havn't checked it with a meter but i think the spectro runs off 5 volts. There is a socket on it for a plugpack.

 

[diachi]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

That 610 is odd. Thats with both fibres plugged into the combiner, or what ever it realy is. Maybe it has something inside it causing the frequency shift. The spectro reading of the 473 is shining both fibres together. Doing it thay way only 473 was present.

That beam shot is from the output module. I can do another from the fibre output.

The beam is strange. Maybe its how fibres work. Letting the beam expand to a few inches its not just a large circular dot. Its made up of hundreds of tiny dots. I can probably get a shot of that.

Its late here and i didnt have much time to test it.

I havn't checked it with a meter but i think the spectro runs off 5 volts. There is a socket on it for a plugpack.

Yeah, must be something fluorescing or another light source causing the 610.

That output is far better than the output from the last one I had, probably due to the pump correction. That's why I had to ask if it was the fiber output, it's nice and round!

The "dots" sound like speckle to me. See here: https://en.wikipedia.org/wiki/Speckle_pattern

 

[paul1598419]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Interesting, Mosc007. I found the integration time on my software is so slow it can't lock and hold a spectrum long enough to even read it. I see your base line is high on the intensity axis when nothing is being read. Your software seems to have some advantages mine does not. I would like to get together and see if there is a way to make this software completely usable. Unfortunately, I have my day and tomorrow locked down for most of the day.

 

[diachi]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

I believe my unit is at the post office. Got a card today, not available for collection until after 1PM tomorrow unfortunately. Will update when I get to the post office tomorrow.

 

[paul1598419]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

As I thought, this has the baffles in it. Once I removed them it started reading more like it should. The calibration is off, but since it is not a linear calibration, it is off more in some areas than others. My 477nm actually measured quite close to that wavelength, but a 532nm measured ~545nm. This software cuts off on the ends of the full spectrum it is said to be aligned for, so I couldn't measure some WL with it. Like my 660nm was off scale on this software. It seems highly unlikely that any calibration will be off by the same amount and in the same direction throughout the whole spectrum.

Brad, are you certain the baffles aren't inside yours? The are small and easy to miss. It sure sounds like they are in yours from what you have said.

 

[CynicalBrad]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

I took a picture of the innards of mine. I THINK it is one page three. There were definitely no baffles in mine though. The calibration info on the sticker did mention pixel 1310 though out of I believe 2048 from some digging so mine could be very poorly aligned as the software won't show anything as less then 500nm or so and the rest of the readings are all in a narrow range. It picked up a high cri led light as a nice wide band iirc 30nm wide.

 

[paul1598419]

Re: B&Wtech 473nm unit / Spectrometer Mods & Info

There are many possibilities for your spectrometer acting the way it does. Alignment seems unlikely. Could be any of the optics damaged including the CCD. Alignment of these does not look easy as the bench is part of the whole PCB, which is larger than the optical bench itself. Trying to adjust all the optics on this one looks like a nightmare to me. I'm really hoping that alignment isn't necessary on these as it could be a very protracted process.