J
Jan Panteltje
Guest
on chip spectrometer?
https://www.sciencedaily.com/releases/2022/10/221020140615.htm
https://www.sciencedaily.com/releases/2022/10/221020140615.htm
M
Martin Brown
Guest
On 23/10/2022 06:39, Jan Panteltje wrote:
Possibly. I\'d like to see a bit more of the specifications and light
intensity it requires before I take that press release at face value.
There is a bit more here but the main article is behind a paywall
https://www.science.org/doi/10.1126/science.add8544
--
Regards,
Martin Brown
Possibly. I\'d like to see a bit more of the specifications and light
intensity it requires before I take that press release at face value.
There is a bit more here but the main article is behind a paywall
https://www.science.org/doi/10.1126/science.add8544
--
Regards,
Martin Brown
J
Jan Panteltje
Guest
On a sunny day (Sun, 23 Oct 2022 09:13:53 +0100) it happened Martin Brown
<\'\'\'newspam\'\'\'@nonad.co.uk> wrote in <tj2t42$1jlg$1@gioia.aioe.org>:
I see.
Well, CCD sensor with prism in front of it should work too?
<\'\'\'newspam\'\'\'@nonad.co.uk> wrote in <tj2t42$1jlg$1@gioia.aioe.org>:
On 23/10/2022 06:39, Jan Panteltje wrote:
on chip spectrometer?
https://www.sciencedaily.com/releases/2022/10/221020140615.htm
Possibly. I\'d like to see a bit more of the specifications and light
intensity it requires before I take that press release at face value.
There is a bit more here but the main article is behind a paywall
https://www.science.org/doi/10.1126/science.add8544
I see.
Well, CCD sensor with prism in front of it should work too?
M
Martin Brown
Guest
On 23/10/2022 09:38, Jan Panteltje wrote:
The best super high resolution systems use an echelle method modest
dispersion prism one way and a very high dispersion grating at almost 90
degrees to it so as to map a linear spectrum onto a 2D rectangular CCD.
https://solarsystem.nasa.gov/resources/390/the-solar-spectrum/
That example was actually observed with a Fourier transform method and
then displayed in the fashion of a traditional echelle spectrum. It is a
very impressive piece of kit even it it only works on bright stars:
https://www.jstor.org/stable/26660057#metadata_info_tab_contents
This is a real physical highres echelle spectroscope
https://www.shelyak.com/le-woppshel-un-spectro-echelle-a-grande-resolution/?lang=en
They are seriously nice pieces of kit. PE did an atomic
absorption/emission spectroscope using a similar configuration and early
CCDs back in the 1990\'s. Must have been ~95 because I saw it in Japan at
one of the big analytical trade fairs where we were also exhibiting.
--
Regards,
Martin Brown
On a sunny day (Sun, 23 Oct 2022 09:13:53 +0100) it happened Martin Brown
\'\'\'newspam\'\'\'@nonad.co.uk> wrote in <tj2t42$1jlg$1@gioia.aioe.org>:
On 23/10/2022 06:39, Jan Panteltje wrote:
on chip spectrometer?
https://www.sciencedaily.com/releases/2022/10/221020140615.htm
Possibly. I\'d like to see a bit more of the specifications and light
intensity it requires before I take that press release at face value.
There is a bit more here but the main article is behind a paywall
https://www.science.org/doi/10.1126/science.add8544
I see.
Well, CCD sensor with prism in front of it should work too?
The best super high resolution systems use an echelle method modest
dispersion prism one way and a very high dispersion grating at almost 90
degrees to it so as to map a linear spectrum onto a 2D rectangular CCD.
https://solarsystem.nasa.gov/resources/390/the-solar-spectrum/
That example was actually observed with a Fourier transform method and
then displayed in the fashion of a traditional echelle spectrum. It is a
very impressive piece of kit even it it only works on bright stars:
https://www.jstor.org/stable/26660057#metadata_info_tab_contents
This is a real physical highres echelle spectroscope
https://www.shelyak.com/le-woppshel-un-spectro-echelle-a-grande-resolution/?lang=en
They are seriously nice pieces of kit. PE did an atomic
absorption/emission spectroscope using a similar configuration and early
CCDs back in the 1990\'s. Must have been ~95 because I saw it in Japan at
one of the big analytical trade fairs where we were also exhibiting.
--
Regards,
Martin Brown
J
John Larkin
Guest
On Sun, 23 Oct 2022 05:39:23 GMT, Jan Panteltje
<pNaOnStPeAlMtje@yahoo.com> wrote:
I\'ve always wanted a handheld DVM-like spectrometer that covers a wide
range, specifically 1600 to 300 nm to verify LED and laser
wavelengths.
<pNaOnStPeAlMtje@yahoo.com> wrote:
I\'ve always wanted a handheld DVM-like spectrometer that covers a wide
range, specifically 1600 to 300 nm to verify LED and laser
wavelengths.
J
John Larkin
Guest
On Sun, 23 Oct 2022 14:27:56 +0100, Martin Brown
<\'\'\'newspam\'\'\'@nonad.co.uk> wrote:
The spectrometer business seems to be a race for resolution in narrow
bands. There\'s no wide-range low-resolution stuff that we can find.
Something like a grating and a bunch of detectors could work. It would
have a lot of wavelength overlap confusion which could be mostly
computed out.
<\'\'\'newspam\'\'\'@nonad.co.uk> wrote:
On 23/10/2022 09:38, Jan Panteltje wrote:
On a sunny day (Sun, 23 Oct 2022 09:13:53 +0100) it happened Martin Brown
\'\'\'newspam\'\'\'@nonad.co.uk> wrote in <tj2t42$1jlg$1@gioia.aioe.org>:
On 23/10/2022 06:39, Jan Panteltje wrote:
on chip spectrometer?
https://www.sciencedaily.com/releases/2022/10/221020140615.htm
Possibly. I\'d like to see a bit more of the specifications and light
intensity it requires before I take that press release at face value.
There is a bit more here but the main article is behind a paywall
https://www.science.org/doi/10.1126/science.add8544
I see.
Well, CCD sensor with prism in front of it should work too?
The best super high resolution systems use an echelle method modest
dispersion prism one way and a very high dispersion grating at almost 90
degrees to it so as to map a linear spectrum onto a 2D rectangular CCD.
https://solarsystem.nasa.gov/resources/390/the-solar-spectrum/
That example was actually observed with a Fourier transform method and
then displayed in the fashion of a traditional echelle spectrum. It is a
very impressive piece of kit even it it only works on bright stars:
https://www.jstor.org/stable/26660057#metadata_info_tab_contents
This is a real physical highres echelle spectroscope
https://www.shelyak.com/le-woppshel-un-spectro-echelle-a-grande-resolution/?lang=en
They are seriously nice pieces of kit. PE did an atomic
absorption/emission spectroscope using a similar configuration and early
CCDs back in the 1990\'s. Must have been ~95 because I saw it in Japan at
one of the big analytical trade fairs where we were also exhibiting.
The spectrometer business seems to be a race for resolution in narrow
bands. There\'s no wide-range low-resolution stuff that we can find.
Something like a grating and a bunch of detectors could work. It would
have a lot of wavelength overlap confusion which could be mostly
computed out.
J
Jan Panteltje
Guest
On a sunny day (Sun, 23 Oct 2022 08:10:42 -0700) it happened John Larkin
<jlarkin@highlandSNIPMEtechnology.com> wrote in
<96malhldkco3pnjog22sqb7dq8jm4c7hdb@4ax.com>:
That should not be difficult to make
In the UNI we had small spectrometers that consisted of a rotating prism
and a photocell looking at it through a slot (to look at a spectral line)
A \'white\' light source and a tube with the stuff that had to
be investigated in the light beam.
Big knob on top to rotate the prism, the knob had a scale with numbers on it,
the wavelength.
Small box, 3x3 inch or so I think.
Had to repair one once.
You could perhaps use a rotating prism, a slot and a photocell, tune for maximum and
read the rotation from the knob?
<jlarkin@highlandSNIPMEtechnology.com> wrote in
<96malhldkco3pnjog22sqb7dq8jm4c7hdb@4ax.com>:
That should not be difficult to make
In the UNI we had small spectrometers that consisted of a rotating prism
and a photocell looking at it through a slot (to look at a spectral line)
A \'white\' light source and a tube with the stuff that had to
be investigated in the light beam.
Big knob on top to rotate the prism, the knob had a scale with numbers on it,
the wavelength.
Small box, 3x3 inch or so I think.
Had to repair one once.
You could perhaps use a rotating prism, a slot and a photocell, tune for maximum and
read the rotation from the knob?
R
Rich S
Guest
On Sunday, October 23, 2022 at 8:14:03 AM UTC, Martin Brown wrote:
try this one Martin
https://www.nature.com/articles/s41467-022-32306-z
On 23/10/2022 06:39, Jan Panteltje wrote:
on chip spectrometer?
https://www.sciencedaily.com/releases/2022/10/221020140615.htm
Possibly. I\'d like to see a bit more of the specifications and light
intensity it requires before I take that press release at face value.
There is a bit more here but the main article is behind a paywall
https://www.science.org/doi/10.1126/science.add8544
--
Regards,
Martin Brown
try this one Martin
https://www.nature.com/articles/s41467-022-32306-z
J
John Larkin
Guest
On Sun, 23 Oct 2022 15:26:39 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:
The challenge is to make a spectrometer with a wide wavelength range.
It would at least need several detectors, and a prism or grating that
would work over about a 5:1 wavelength range.
Nobody seems to make one.
We\'re lucky in electronics. We can easily measure resistance and
capacitance and frequency over million or billion or sometimes
trillion-to-one spans.
Our Keysight counter can measure picoseconds to kiloseconds, microHz
to gigahertz.
A Fluke DVM can measure microvolts and kilovolts.
I can measure femtofarads to kilofarads with the gear on my little
workbench.
<pNaonStpealmtje@yahoo.com> wrote:
The challenge is to make a spectrometer with a wide wavelength range.
It would at least need several detectors, and a prism or grating that
would work over about a 5:1 wavelength range.
Nobody seems to make one.
We\'re lucky in electronics. We can easily measure resistance and
capacitance and frequency over million or billion or sometimes
trillion-to-one spans.
Our Keysight counter can measure picoseconds to kiloseconds, microHz
to gigahertz.
A Fluke DVM can measure microvolts and kilovolts.
I can measure femtofarads to kilofarads with the gear on my little
workbench.
J
Jan Panteltje
Guest
On a sunny day (Sun, 23 Oct 2022 09:58:18 -0700) it happened John Larkin
<jlarkin@highlandSNIPMEtechnology.com> wrote in
<m0salh9pp7c3gqortagaj6ualh9g23ar4n@4ax.com>:
If you a need wide range IR detector:
https://www.irlabs.com/products/bolometers/bolometer-systems/#:~:text=Bolometers%20are%20detectors%20used%20to,5000%C2%B5m%20(30THz%20to%2060GHz).
20 THz to 150 GHz 15 to 2000 um
I have a cryocooler also workbench size.
You have a very strong signal using laser output,
should make things easier.
Or you could perhaps use reference LEDs or laser diodes and go for interference
in some crystal. non-linearity is your friend
<jlarkin@highlandSNIPMEtechnology.com> wrote in
<m0salh9pp7c3gqortagaj6ualh9g23ar4n@4ax.com>:
If you a need wide range IR detector:
https://www.irlabs.com/products/bolometers/bolometer-systems/#:~:text=Bolometers%20are%20detectors%20used%20to,5000%C2%B5m%20(30THz%20to%2060GHz).
20 THz to 150 GHz 15 to 2000 um
I have a cryocooler also workbench size.
You have a very strong signal using laser output,
should make things easier.
Or you could perhaps use reference LEDs or laser diodes and go for interference
in some crystal. non-linearity is your friend
J
John Larkin
Guest
On Sun, 23 Oct 2022 17:23:12 GMT, Jan Panteltje
<pNaonStpealmtje@yahoo.com> wrote:
I want a spectrometer. We don\'t need quantified power measurement but
it would be nice.
We buy all sorts of lasers and LEDs and we can\'t be sure they are the
right wavelength. Even 1% wavelength resolution would be plenty.
Nobody makes it.
<pNaonStpealmtje@yahoo.com> wrote:
I want a spectrometer. We don\'t need quantified power measurement but
it would be nice.
We buy all sorts of lasers and LEDs and we can\'t be sure they are the
right wavelength. Even 1% wavelength resolution would be plenty.
Nobody makes it.
W
whit3rd
Guest
On Sunday, October 23, 2022 at 10:49:29 AM UTC-7, John Larkin wrote:
I don\'t know what \'all sorts\' means, but for red visible and most IR, a silicon
photodiode is a good detector. A grating (those start at a dollar or so)
and a protractor will complete the ensemble. You already have a milliammeter, I trust.
A metal ruler is a good enough grating to measure the wavelength of a red HeNe laser.
For really wide bandwidth, you\'d want a chopper and do photoacoustic detection,
with a reflective grating (about $100 at Edmund ).
What the market mainly offers, is calibrated spectrum analyzers (i.e. overkill for a test setup).
I don\'t know what \'all sorts\' means, but for red visible and most IR, a silicon
photodiode is a good detector. A grating (those start at a dollar or so)
and a protractor will complete the ensemble. You already have a milliammeter, I trust.
A metal ruler is a good enough grating to measure the wavelength of a red HeNe laser.
For really wide bandwidth, you\'d want a chopper and do photoacoustic detection,
with a reflective grating (about $100 at Edmund ).
What the market mainly offers, is calibrated spectrum analyzers (i.e. overkill for a test setup).
R
Rich S
Guest
On Sunday, October 23, 2022 at 7:04:21 PM UTC, whit3rd wrote:
would this work? Handheld, ca. $1500,
https://www.intl-lighttech.com/products/ilt350-chroma-meter
would this work? Handheld, ca. $1500,
https://www.intl-lighttech.com/products/ilt350-chroma-meter
J
Joe Gwinn
Guest
On Sun, 23 Oct 2022 10:49:22 -0700, John Larkin
<jlarkin@highlandSNIPMEtechnology.com> wrote:
One can cobble something together with a replica grating and a silicon
photo detector array of some kind.
..<https://www.sargentwelch.com/store/product/8885837/replica-diffraction-gratings>
This is one example. There are many others.
You will need a calibration source of some kind. A neon tube or the
like, to provide some known lines for reference.
Joe Gwinn
<jlarkin@highlandSNIPMEtechnology.com> wrote:
One can cobble something together with a replica grating and a silicon
photo detector array of some kind.
..<https://www.sargentwelch.com/store/product/8885837/replica-diffraction-gratings>
This is one example. There are many others.
You will need a calibration source of some kind. A neon tube or the
like, to provide some known lines for reference.
Joe Gwinn
J
Joe Gwinn
Guest
On Sun, 23 Oct 2022 12:04:17 -0700 (PDT), whit3rd <whit3rd@gmail.com>
wrote:
If we\'re talking thousands of dollars, I\'d look at Ocean ST VIS
Microspectrometers:
..<https://www.oceaninsight.com/products/spectrometers/microspectrometer/st-series-spectrometer/ocean-st-vis-microspectrometer/>
Their larger units have wider acceptance ranges, typically two bands,
(like VIZ _and_ NIR) versus just one (VIS _or_ NIR).
Joe Gwinn
wrote:
If we\'re talking thousands of dollars, I\'d look at Ocean ST VIS
Microspectrometers:
..<https://www.oceaninsight.com/products/spectrometers/microspectrometer/st-series-spectrometer/ocean-st-vis-microspectrometer/>
Their larger units have wider acceptance ranges, typically two bands,
(like VIZ _and_ NIR) versus just one (VIS _or_ NIR).
Joe Gwinn
J
John Larkin
Guest
On Sun, 23 Oct 2022 12:04:17 -0700 (PDT), whit3rd <whit3rd@gmail.com>
wrote:
\"Don\'t be a jerk. Nobody likes jerks.\"
wrote:
\"Don\'t be a jerk. Nobody likes jerks.\"
J
John Larkin
Guest
On Sun, 23 Oct 2022 12:34:11 -0700 (PDT), Rich S
<richsulinengineer@gmail.com> wrote:
That covers the visible, which would check the colors of LEDs, which
is not really much of a problem.
The more serious problem is that we buy a bunch of lasers in the 800
to 1550 sort of range and we\'d like to make sure they are right.
<richsulinengineer@gmail.com> wrote:
That covers the visible, which would check the colors of LEDs, which
is not really much of a problem.
The more serious problem is that we buy a bunch of lasers in the 800
to 1550 sort of range and we\'d like to make sure they are right.
J
John Larkin
Guest
On Sun, 23 Oct 2022 15:42:32 -0400, Joe Gwinn <joegwinn@comcast.net>
wrote:
How wide a spectral range can a grating cover before things get
ambiguous?
I was thinking that a grating could fire into several detectors, each
with a different spectral range, and the resulting confusion might be
sorted out in software.
wrote:
How wide a spectral range can a grating cover before things get
ambiguous?
I was thinking that a grating could fire into several detectors, each
with a different spectral range, and the resulting confusion might be
sorted out in software.
W
whit3rd
Guest
On Sunday, October 23, 2022 at 2:19:55 PM UTC-7, John Larkin wrote:
Huh? If you just want to distinguish 850 from 1350 nm, that\'s no problem.
The $1 replica that looks like a 35mm slide will do it fine. You can worry about
blaze angles and UV transmission (the slide is a transparency, but not to UV) and
line spacing fineries, but why?
Or, you could swing a detector over a range of angles and register a \'hit\'.
It\'ll take only seconds, why bother with a computer analysis?
Huh? If you just want to distinguish 850 from 1350 nm, that\'s no problem.
The $1 replica that looks like a 35mm slide will do it fine. You can worry about
blaze angles and UV transmission (the slide is a transparency, but not to UV) and
line spacing fineries, but why?
Or, you could swing a detector over a range of angles and register a \'hit\'.
It\'ll take only seconds, why bother with a computer analysis?
J
John Larkin
Guest
On Sun, 23 Oct 2022 15:44:10 -0700 (PDT), whit3rd <whit3rd@gmail.com>
wrote:
I don\'t think a grating will cast a wavelenght-linear unambiguous
image over a wide spectral range, like 5:1 or so.
I think the 700 nm lines will wind up on top of the 1400\'s. And
probably much worse.
https://tinyurl.com/ext8r82d
\"The diffracted beams of different colors and corresponding to
consecutive orders can overlap, this phenomenon becomes more likely to
grow in the order of diffraction.\"
wrote:
I don\'t think a grating will cast a wavelenght-linear unambiguous
image over a wide spectral range, like 5:1 or so.
I think the 700 nm lines will wind up on top of the 1400\'s. And
probably much worse.
https://tinyurl.com/ext8r82d
\"The diffracted beams of different colors and corresponding to
consecutive orders can overlap, this phenomenon becomes more likely to
grow in the order of diffraction.\"