Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

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

Joined
Jan 21, 2018
Messages
324
Points
43
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

I'm pretty sure I posted this before, but here it is again. My neon actually matches google results, so you might have a lot more aligning to do.

nzZcrSr.png




Have a running acquisition so you can monitor the spectrum in real-time. Start the light source a few feet away with the fibre or the slit pointing at it. Bring the light source closer and closer until the largest peak is somewhere between 30,000-65,000 counts. The latter being ideal, but the former is generally good enough. Much lower than this, and you run a greater risk of the noise floor masking smaller emissions. Any higher than this, you saturate the sensor, causing the peak to be "clipped".

Hi , could you please have a look at the peek 616.4, i had an error while using this in one calibration and guess it should be 614.3 ?
 





Encap

0
Joined
May 14, 2011
Messages
6,110
Points
113
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Was I wrong? Was I rude?

Someone asked why all the extra digits were there, and I pointed out most people don't know they're useless. How is that problematic? I answered a question with an honest response. If you think providing an accurate assessment is somehow hindering progress, you need to re-evaluate your priorities and perhaps grow some thicker skin.

You're telling me some people are afraid to post because they might have something wrong? That they might benefit from verifying their information before posting so that is factually sound? I don't understand. I don't understand how that's a problem. What's the alternative? That people have no fear of being corrected or criticized? That's the community you want?

Science and technology thrives because it is OPEN to criticism. Abhorrence to criticism is fundamentally incompatible with science.

Excellent points---well said.
 
Joined
Jan 21, 2018
Messages
324
Points
43
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Hello, I would like to refresh this with a new facet. As you know, this series also comes with te cooling. This unit can also be queried accordingly. I have analyzed and decomposed a unit completely. A direct sensor does not suit it. How is this realized? Although I have an idea ... but if necessary, does it know someone without speculation ...?

++++++

sorry it seems to be not a good idea to use an automatic translation into english, but this is not my native tongue (like village people said ... :) ).
 
Last edited:

LSRFAQ

0
Joined
May 8, 2009
Messages
1,155
Points
83
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Hi , could you please have a look at the peek 616.4, i had an error while using this in one calibration and guess it should be 614.3 ?

nearest NE lines from the database.

614.3062 nm
616.3593
618.2146
Steve.
 
Last edited:

TomP

0
Joined
May 9, 2018
Messages
8
Points
3
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

I am not sure if you were talking about the laser or spectrometer cooling, but the laser appears to have a thermistor for each TEC at least.

pinc7CO.jpg


Speaking of, if anyone has made any headway on the laser controller other than the old info on photon lexicon, I'm trying to figure out how to change the setpoint of that board, and running into difficulties with the serial ports. Trying not to resort to brute forcing the command set.

The spectrometer detector is interesting. If it is TEC cooled on my unit, it is part of the chip itself (and if so then the thermal measurement would also be in there) It doesn't have any thermal contact to the heatsink itself, which is quite interesting. One potential pointer is the capacitor on the right of the detector, which could be for the cooler.

SywREt3.jpg
 
Last edited:
Joined
Sep 20, 2013
Messages
17,252
Points
113
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

As far as I know, the only TECs on these units are in the laser head. There is a fan on the spectrometer, there to allow for longer integration times, but I don't see it doing that much good for what I'll be using these for.
 
Joined
Jan 21, 2018
Messages
324
Points
43
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

As far as I know, the only TECs on these units are in the laser head. There is a fan on the spectrometer, there to allow for longer integration times, but I don't see it doing that much good for what I'll be using these for.

Yes so it is, our spectrometer device type BTC110S has no cooler, but i have seen that the brothers like BTC112 has a TE-cooler AND i found, that you can query the temperature of the BTC110S :

?t
?t
ACK
00049

but my question is why and where is the sensor and how can i translate "00049" (or other numbers after ?t ).
if there is really the posibility to read the temperatur of the spectrometer, maybe we could mod the device by adding a TE-cooler which is controlled by using the querry ?t .
 
Joined
Sep 26, 2016
Messages
52
Points
8
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Yes so it is, our spectrometer device type BTC110S has no cooler, but i have seen that the brothers like BTC112 has a TE-cooler AND i found, that you can query the temperature of the BTC110S :

?t
?t
ACK
00049

but my question is why and where is the sensor and how can i translate "00049" (or other numbers after ?t ).
if there is really the posibility to read the temperatur of the spectrometer, maybe we could mod the device by adding a TE-cooler which is controlled by using the querry ?t .

I'm not sure where the temp sensor would be, I've looked around the PCB and under the black case but nothing stands out at that it might be it.

I've considered the TEC option as well but not sure where you would mount it and have any decent results with it.


On another note, I was able to finish building my black box and I put the spectrometer and battery driven CFL bulb in it and took another reading. The attached image is what I got.
 

Attachments

  • CFL_Spectrum_Black_Box_Small.png
    CFL_Spectrum_Black_Box_Small.png
    77.4 KB · Views: 37
Joined
Jan 21, 2018
Messages
324
Points
43
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

At some sites i found the information that the sony ilx511 has 2086 pixels, see here the details:

"A typical example of a linear CCD is the Sony ILX511, which is an array of 2086 pixels, each 14 μm wide and 200 μm high. This pixel format is ideally suited to spectrometers with a narrow, but tall entrance slit.
A metal film covers the first 32 pixels and the last 6 pixels of the array so these do not respond to light, leaving 2048 effective pixels. The film-covered pixels are called “dark pixels”. This sensor is extremely sensitive, allowing very faint optical signatures to be recorded if a long enough exposure time is employed.
A CCD processing engine described here is specifically designed for use with the ILX511, however similar linear sensors can be easily accommodated."

Source :

Spectrometers

This could be found also in the datasheet (see attachment).

These dark pixels are used basicly as referenz to the optical ones, i do not know, but may these aditional pixels be used also as temperatur-sensor?
 

Attachments

  • Capture.JPG
    Capture.JPG
    130.8 KB · Views: 28
Joined
Sep 26, 2016
Messages
52
Points
8
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

At some sites i found the information that the sony ilx511 has 2086 pixels, see here the details:

"A typical example of a linear CCD is the Sony ILX511, which is an array of 2086 pixels, each 14 μm wide and 200 μm high. This pixel format is ideally suited to spectrometers with a narrow, but tall entrance slit.
A metal film covers the first 32 pixels and the last 6 pixels of the array so these do not respond to light, leaving 2048 effective pixels. The film-covered pixels are called “dark pixels”. This sensor is extremely sensitive, allowing very faint optical signatures to be recorded if a long enough exposure time is employed.
A CCD processing engine described here is specifically designed for use with the ILX511, however similar linear sensors can be easily accommodated."

Source :

Spectrometers

This could be found also in the datasheet (see attachment).

These dark pixels are used basicly as referenz to the optical ones, i do not know, but may these aditional pixels be used also as temperatur-sensor?

I couldn't find anything in the datasheet that would indicate that. Not saying it can't, just saying I didn't see anything like that mentioned there.

Some microcontrollers/microprocessors have built in temp sensors and it may be reading out the chip's temp with that command. Hard to know for sure without the source code though.
 

diber

0
Joined
Mar 14, 2018
Messages
47
Points
8
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

I tend to agree with Agastar on this. I have been involved in the development of space-borne imagers (not hands-on, but close enough to have seen quite a number of details here and there) and for such imagers, these dark pixels are used in the image processing, but not in the actual temperature control. In such instruments, dedicated temperature sensors are used in order to keep the control loop simple and robust. In the data processing, both the temperature sensor data (afaik external sensor, not embedded in the CCD itself) and the dark pixels are used (as far as I remember, the dark pixels more to monitor the evolution of the dark signal over the lifetime of the detector, for the rest dark signal calibration data acquired as a function of temperature on ground or dark images acquired in-orbit) are used in the data processing to improve the resulting images. Similar calibration (dark noise, individual pixel sensitivity (PRNU) etc...) and data processing techniques can be (and probably are) used to improve the spectra acquired by CCD sensors.

On the other hand, dark noise is indeed varying as a function of temperature... maybe it is possible to use it in the thermal control loop and possibly even done. I just haven't seen it being used as such.
 

TomP

0
Joined
May 9, 2018
Messages
8
Points
3
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Chloderic, have you tried taking a hair dryer to some of the ic's? It might be that the temp reading is not a part of the ccd at all (is it even necessarily temperature at all?). Lightly warm the CPLD and see if the number changes.
 
Joined
Mar 1, 2017
Messages
81
Points
8
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

Yes so it is, our spectrometer device type BTC110S has no cooler, but i have seen that the brothers like BTC112 has a TE-cooler AND i found, that you can query the temperature of the BTC110S :

?t
?t
ACK
00049

but my question is why and where is the sensor and how can i translate "00049" (or other numbers after ?t ).
if there is really the posibility to read the temperatur of the spectrometer, maybe we could mod the device by adding a TE-cooler which is controlled by using the querry ?t .

Hi guys,
I can confirme that the the used unit sold on ebay and that we are discussing here is not TEC.
And to TEC a spectrometer, it is not an easy stuff, as the condensation can occur on the ccd itself or on the board.
the TEC unit should be isolated and be in contact ONLY with the detector.
But of course, there are lot of DIY videos but no one isolate the CCD and the TEC from ambiant humidity.

C
 
Joined
Feb 2, 2012
Messages
577
Points
43
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

As well as the Noble gas Ampules I ordered from Ebay I also Ordered 2 Spectral Discharge tubes from a local supplier in Aus. They arrived today.

I now have a Mercury and a Helium Spectral Discharge tube to calibrate the Spectro as accurately as I can. I chose Mercury and Helium as they only have a few lines which will make calibration easier. I have looked at Neon and it has so many spectral lines it would be very difficult to find which is which for calibration.

This will be a weekend job. I have some small CCFL drivers I will test them with. They should be close enough to get them to ignite. Wont be as much power though. If that doesn't work I can try a HeNe laser supply. That will supply more current. The Tubes rating is for 10 ma into them. About 2kv to ignite them.
 
Joined
Feb 2, 2012
Messages
577
Points
43
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

I was asked by a member how to calculate the 3rd order Polynomial values to Calibrate the Spectrometer using my Spectro Software. And maybe other software as well.

I created a thread with detailed instructions, and Pictures, to show how to do the calculation in Excel.

Spectrometer Calibration Calculation
 
Last edited:
Joined
Sep 26, 2016
Messages
52
Points
8
Re: B&Wtech 473nm unit / Spectrometer Mods & Info

As well as the Noble gas Ampules I ordered from Ebay I also Ordered 2 Spectral Discharge tubes from a local supplier in Aus. They arrived today.

I now have a Mercury and a Helium Spectral Discharge tube to calibrate the Spectro as accurately as I can. I chose Mercury and Helium as they only have a few lines which will make calibration easier. I have looked at Neon and it has so many spectral lines it would be very difficult to find which is which for calibration.

This will be a weekend job. I have some small CCFL drivers I will test them with. They should be close enough to get them to ignite. Wont be as much power though. If that doesn't work I can try a HeNe laser supply. That will supply more current. The Tubes rating is for 10 ma into them. About 2kv to ignite them.

I ordered some as well and mine have arrived too :D I picked up Neon, Xenon, Argon, and Nitrogen. I thought I had ordered Helium but I guess not lol.

The driver that came with the lights is 2K @ 10mA out and runs on a 12V power supply. It lights them up nicely. I want to make a nice holder for these units. like the one I found on Amazon (Link). Right now I just have a black cardboard box lined with black construction paper :)

Looking forward to seeing any pics you want to share when you get yours up and running :). I'll post some as well as soon as I get it all setup and running.
 




Top