Counting photons with an MPPC

[Phil Hobbs]

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators. Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

<https://electrooptical.net/www/sed/MPPCphotonCounting.mts>

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[John Larkin]

On Wed, 21 Aug 2019 18:18:53 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators. Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts

Cheers

Phil Hobbs

That's pretty sensitive to voltage. What's the background count rate
like?

Why is your workbench so neat?

 

[Phil Hobbs]

On 8/21/19 6:28 PM, John Larkin wrote:

On Wed, 21 Aug 2019 18:18:53 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver,
voltage-controlled amplifier, and APD bias) plus a handwired
pHEMT-boostrapped front end and a box of voltage regulators. Works
from single photons up to about 4 mA in one range.

This video shows it counting photons, which I still think is a
cool thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts


That's pretty sensitive to voltage.

It sure is. Gain doubles in roughly a volt.

> What's the background count rate like?

About 200 kHz at room temperature, maybe 10 kHz at -10C, which is where
it's set to. For the cathodoluminescence application it hardly matters
because you need > 2 MHz count rates to get a decent image in a
reasonable time.

Why is your workbench so neat?

<https://www.gocomics.com/calvinandhobbes/1992/09/17/>

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

On Wed, 21 Aug 2019 19:00:51 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 8/21/19 6:28 PM, John Larkin wrote:
On Wed, 21 Aug 2019 18:18:53 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver,
voltage-controlled amplifier, and APD bias) plus a handwired
pHEMT-boostrapped front end and a box of voltage regulators. Works
from single photons up to about 4 mA in one range.

This video shows it counting photons, which I still think is a
cool thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts


That's pretty sensitive to voltage.

It sure is. Gain doubles in roughly a volt.

What's the background count rate like?

About 200 kHz at room temperature, maybe 10 kHz at -10C, which is where
it's set to. For the cathodoluminescence application it hardly matters
because you need > 2 MHz count rates to get a decent image in a
reasonable time.


Why is your workbench so neat?

https://www.gocomics.com/calvinandhobbes/1992/09/17/>

Cheers

Phil Hobbs

When I was a kid, I slept on a tiny strip of my bed. The rest was
covered with electronics. My mom wouldn't go into my room for years.

 

[Phil Hobbs]

On 8/21/19 7:38 PM, jlarkin@highlandsniptechnology.com wrote:

On Wed, 21 Aug 2019 19:00:51 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 8/21/19 6:28 PM, John Larkin wrote:
On Wed, 21 Aug 2019 18:18:53 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver,
voltage-controlled amplifier, and APD bias) plus a handwired
pHEMT-boostrapped front end and a box of voltage regulators. Works
from single photons up to about 4 mA in one range.

This video shows it counting photons, which I still think is a
cool thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts


That's pretty sensitive to voltage.

It sure is. Gain doubles in roughly a volt.

What's the background count rate like?

About 200 kHz at room temperature, maybe 10 kHz at -10C, which is where
it's set to. For the cathodoluminescence application it hardly matters
because you need > 2 MHz count rates to get a decent image in a
reasonable time.


Why is your workbench so neat?

https://www.gocomics.com/calvinandhobbes/1992/09/17/>

Cheers

Phil Hobbs

When I was a kid, I slept on a tiny strip of my bed. The rest was
covered with electronics. My mom wouldn't go into my room for years.

I had to keep my stuff on the floor, because otherwise the cat would
have gradually pushed me off the edge.

Cheers

Phil Hobbs

(Whose most recent cat shuffled off this mortal coil about 15 years ago.)

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 8/21/19 8:54 PM, jlarkin@highlandsniptechnology.com wrote:

On Wed, 21 Aug 2019 19:45:33 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 8/21/19 7:38 PM, jlarkin@highlandsniptechnology.com wrote:
On Wed, 21 Aug 2019 19:00:51 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 8/21/19 6:28 PM, John Larkin wrote:
On Wed, 21 Aug 2019 18:18:53 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver,
voltage-controlled amplifier, and APD bias) plus a handwired
pHEMT-boostrapped front end and a box of voltage regulators. Works
from single photons up to about 4 mA in one range.

This video shows it counting photons, which I still think is a
cool thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts


That's pretty sensitive to voltage.

It sure is. Gain doubles in roughly a volt.

What's the background count rate like?

About 200 kHz at room temperature, maybe 10 kHz at -10C, which is where
it's set to. For the cathodoluminescence application it hardly matters
because you need > 2 MHz count rates to get a decent image in a
reasonable time.


Why is your workbench so neat?

https://www.gocomics.com/calvinandhobbes/1992/09/17/>

Cheers

Phil Hobbs

When I was a kid, I slept on a tiny strip of my bed. The rest was
covered with electronics. My mom wouldn't go into my room for years.

I had to keep my stuff on the floor, because otherwise the cat would
have gradually pushed me off the edge.

I've known women like that.

But that's a good thing, unlike the cat.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

On Wed, 21 Aug 2019 19:45:33 -0400, Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote:

On 8/21/19 7:38 PM, jlarkin@highlandsniptechnology.com wrote:
On Wed, 21 Aug 2019 19:00:51 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

On 8/21/19 6:28 PM, John Larkin wrote:
On Wed, 21 Aug 2019 18:18:53 -0400, Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver,
voltage-controlled amplifier, and APD bias) plus a handwired
pHEMT-boostrapped front end and a box of voltage regulators. Works
from single photons up to about 4 mA in one range.

This video shows it counting photons, which I still think is a
cool thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts


That's pretty sensitive to voltage.

It sure is. Gain doubles in roughly a volt.

What's the background count rate like?

About 200 kHz at room temperature, maybe 10 kHz at -10C, which is where
it's set to. For the cathodoluminescence application it hardly matters
because you need > 2 MHz count rates to get a decent image in a
reasonable time.


Why is your workbench so neat?

https://www.gocomics.com/calvinandhobbes/1992/09/17/>

Cheers

Phil Hobbs

When I was a kid, I slept on a tiny strip of my bed. The rest was
covered with electronics. My mom wouldn't go into my room for years.

I had to keep my stuff on the floor, because otherwise the cat would
have gradually pushed me off the edge.

I've known women like that.

 

[George Herold]

On Wednesday, August 21, 2019 at 6:19:01 PM UTC-4, Phil Hobbs wrote:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators. Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts

Not loading here...
(OK got it.. pretty cool.)
I've been thinking, reading about photon counting.
Detector efficiency has to be the number one parameter..
(well maybe with time resolution.. short spikey pulses.)

Some of the papers are ~1/2 right, and then miss efficiency.

You've been talking about some photon counting 'white paper'
I hope it has a section on correlated photons.
There's this fact that accidentals go as the flux squared,
and the signal goes as the flux (number of photons.)
So.. given some time resolution, there's an optimal flux..
(signal to noise) that is in between zero and infinity.

George H.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Phil Hobbs]

On 8/21/19 10:16 PM, George Herold wrote:

On Wednesday, August 21, 2019 at 6:19:01 PM UTC-4, Phil Hobbs wrote:
Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators. Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts
Not loading here...
(OK got it.. pretty cool.)
I've been thinking, reading about photon counting.
Detector efficiency has to be the number one parameter..
(well maybe with time resolution.. short spikey pulses.)

Efficiency times fill factor, right.

Some of the papers are ~1/2 right, and then miss efficiency.

But then they would, wouldn't they?

You've been talking about some photon counting 'white paper'
I hope it has a section on correlated photons.

There's this fact that accidentals go as the flux squared,
and the signal goes as the flux (number of photons.)
So.. given some time resolution, there's an optimal flux..
(signal to noise) that is in between zero and infinity.

Dunno how to quantify that in general, but it's definitely worth
thinking about.

Cheers

Phil Hobb


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

[Robert Baer]

Phil Hobbs wrote:

Well, the MPPC demo system is done.  It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators.  Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts

Cheers

Phil Hobbs

What would be beyond "mere" counting, is to listen to their fuzzy
gyrations, the singing, the buzz; in effect, the random existence in a
given space.

 

[Jan Panteltje]

On a sunny day (Wed, 21 Aug 2019 18:18:53 -0400) it happened Phil Hobbs
<pcdhSpamMeSenseless@electrooptical.net> wrote in
<qjkg0h$cl8$1@dont-email.me>:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators. Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts

That movie is a typical waste of bandwidth,
it could be done in a few MB with decent compression.

Before publishing be so kind as to point out the fileseze for those on slower links and limited budget data.
Add some subtitles if explanation is needed.


See
http://panteltje.com/pub/PMT_FEU35_interface_mvi_3210.avi
597440 bytes
Analog scopes do not lie either


Yours:
# mediainfo MPPCphotonCounting.mts
General
ID : 0
Complete name : MPPCphotonCounting.mts
Format : BDAV
Format/Info : BluRay Video
File size : 136 MiB
Duration : 1mn 18s
Overall bit rate : 14.5 Mbps
Maximum Overall bit rate : 18.0 Mbps

Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.0
Format settings, CABAC : No
Format settings, ReFrames : 2 frames
Duration : 1mn 18s
Bit rate : 13.7 Mbps
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16/9
Frame rate : 29.970 fps
Resolution : 24 bits
Colorimetry : 4:2:0
Scan type : Interlaced
Scan order : Top Field First
Bits/(Pixel*Frame) : 0.221
Stream size : 129 MiB (95%)

Audio
ID : 4352 (0x1100)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Duration : 1mn 18s
Bit rate mode : Constant
Bit rate : 192 Kbps
Channel(s) : 2 channels
Channel positions : L R
Sampling rate : 48.0 KHz
Stream size : 1.80 MiB (1%)

Text
ID : 4608 (0x1200)
Menu ID : 1 (0x1)
Format : PGS
Duration : 1mn 18s

 

[Phil Hobbs]

On 8/22/19 9:29 AM, DecadentLinuxUserNumeroUno@decadence.org wrote:

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
news:qjm351$qla$1@dont-email.me:

On 8/22/19 4:27 AM, Jan Panteltje wrote:
On a sunny day (Wed, 21 Aug 2019 18:18:53 -0400) it happened Phil
Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
qjkg0h$cl8$1@dont-email.me>:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver,
voltage-controlled amplifier, and APD bias) plus a handwired
pHEMT-boostrapped front end and a box of voltage regulators.
Works from single photons up to about 4 mA in one range.

This video shows it counting photons, which I still think is a
cool thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts

That movie is a typical waste of bandwidth,
it could be done in a few MB with decent compression.

Kiss my grits.

Cheers

Phil Hobbs

They are looking at single photon spurt devices (for lack of
knowledge of the right term) in the quantum computing realm.

We made power supplies (dynode) for PMTs that are on the F-4
airframe thast can detect single photon events, such as a missile
launch. That is decades old tech.

But the counting thing...

The quantum computer guys like photonic qbits.

"Only God can count that fast..." --unknown

As to the video, I do not know what to do with an mts file.

Run VLC on it. Anything with an H.264 codec should work. (It's the
file format my camera produces natively.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

 

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
news:qjm351$qla$1@dont-email.me:

On 8/22/19 4:27 AM, Jan Panteltje wrote:
On a sunny day (Wed, 21 Aug 2019 18:18:53 -0400) it happened Phil
Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
qjkg0h$cl8$1@dont-email.me>:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver,
voltage-controlled amplifier, and APD bias) plus a handwired
pHEMT-boostrapped front end and a box of voltage regulators.
Works from single photons up to about 4 mA in one range.

This video shows it counting photons, which I still think is a
cool thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts

That movie is a typical waste of bandwidth,
it could be done in a few MB with decent compression.

Kiss my grits.

Cheers

Phil Hobbs

They are looking at single photon spurt devices (for lack of
knowledge of the right term) in the quantum computing realm.

We made power supplies (dynode) for PMTs that are on the F-4
airframe thast can detect single photon events, such as a missile
launch. That is decades old tech.

But the counting thing...

The quantum computer guys like photonic qbits.

"Only God can count that fast..." --unknown

As to the video, I do not know what to do with an mts file.

 

[Phil Hobbs]

On 8/22/19 4:27 AM, Jan Panteltje wrote:

On a sunny day (Wed, 21 Aug 2019 18:18:53 -0400) it happened Phil Hobbs
pcdhSpamMeSenseless@electrooptical.net> wrote in
qjkg0h$cl8$1@dont-email.me>:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators. Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts

That movie is a typical waste of bandwidth,
it could be done in a few MB with decent compression.

Kiss my grits.

Cheers

Phil Hobbs

 

[Joseph Gwinn]

On Aug 21, 2019, Phil Hobbs wrote
(in article <qjkg0h$cl8$1@dont-email.me&gt:

Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators. Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts

What kind of file is this? It promptly crashes on my computer (MacOS). It
appears to have asked for permission to control my computer, specifically
through the accessibility features, which are turned off for security
reasons.

Joe Gwinn

 

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> wrote in
news:qjm6cf$e8q$1@dont-email.me:

On 8/21/19 6:18 PM, Phil Hobbs wrote:

Everybody's a critic. I converted it to mpeg and amended the
link.

Well, the MPPC demo system is done.  It has four of our small
proprietary boards (controller/SMPS, TEC driver,
voltage-controlled amplifier, and APD bias) plus a handwired
pHEMT-boostrapped front end and a box of voltage regulators. 
Works from single photons up to about 4 mA in one range.

This video shows it counting photons, which I still think is a
cool thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mpg

Cheers

Phil Hobbs

I just got done watching it with VLC. Why the assocoation wsa gone
I do not know.

But I never complained...

 

On Thursday, August 22, 2019 at 9:47:01 AM UTC-4, Phil Hobbs wrote:

On 8/21/19 6:18 PM, Phil Hobbs wrote:

Everybody's a critic. I converted it to mpeg and amended the link.

Well, the MPPC demo system is done.  It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators.  Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mpg

Cheers

Phil Hobbs



--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com

lol, then there are those who are not well informed. VLC is the answer to playing almost any video format. Learned about it long time ago. Great program.

 

[Jan Panteltje]

On a sunny day (Thu, 22 Aug 2019 07:09:45 -0700 (PDT)) it happened George
Herold <gherold@teachspin.com> wrote in
<b3786f54-87c2-4607-a4b6-37d0d3fd39da@googlegroups.com>:

That's OK. I'm sorta thinking about it... there's probably a good paper somewhere.
Here is the classic paper by Aspect etal, it gets everything right...
Some later papers seem confused... but the confusion could be in me. :^)
http://www.lac.u-psud.fr/IMG/pdf/anticorrelation_epl.pdf

Figure 2.

If you run at very low count rates, you get no accidentals, but it takes longer to
get enough counts.. and you also run into the dark counts from your detector.

George H.

The way I see it,
1)
photon is just a mathematical construct,

2)
Imagine an ocean full of waves
in it a pole (atom) with a ball (electron) connected to it with a feeble thin wire.
The PMT or whatever semiconductor or ANY detector that detects single electron events
now is a ball detector.

THE BALL WILL BREAK LOSE WHEN THE TOTAL ENERGY PHASE AND AMPLITUDE of the sum of every event in the universe is just right,
Fishysicks then claim 'photon detected'.

So it is in fact also affected by the Voyager spacecraft sending data home.
Sum of waves.

Some then say 'my signal and noise', where my signal is the extra ripples they just created in the pool
by throwing their study book in for example.


I think Planck gave a clear warning that A.E. ignored?


grrrr

 

On Thursday, August 22, 2019 at 10:01:02 AM UTC-4, DecadentLinux...@decadence.org wrote:

jjhudak4@gmail.com wrote in
news:0490f492-9c27-4f56-ae10-6da9a3aa3aca@googlegroups.com:

lol, then there are those who are not well informed. VLC is the
answer to playing almost any video format. Learned about it long
time ago. Great program.


I have been using it since it forst came out. I am pretty sure I
know as much about video as you.

I used to work on the first MPEG-2 satellite equipment.

Not a tech at a TV station.

I was at General Instrument. They went on to develop HDTV.

You probably do know more than me in this area. At one point in my work I was dealing with developing object detection methods (based on various mathematical and ANN classifiers) from many different video formats.
My only point was, of all the programs and tools that I used (or wrote/augmented), VLC was able to play just about any format. That was some time ago and things may have changed, but it still serves me well.
J

 

[George Herold]

On Thursday, August 22, 2019 at 12:17:19 AM UTC-4, Phil Hobbs wrote:

On 8/21/19 10:16 PM, George Herold wrote:
On Wednesday, August 21, 2019 at 6:19:01 PM UTC-4, Phil Hobbs wrote:
Well, the MPPC demo system is done. It has four of our small
proprietary boards (controller/SMPS, TEC driver, voltage-controlled
amplifier, and APD bias) plus a handwired pHEMT-boostrapped front end
and a box of voltage regulators. Works from single photons up to about
4 mA in one range.

This video shows it counting photons, which I still think is a cool
thing to be able to do.

https://electrooptical.net/www/sed/MPPCphotonCounting.mts
Not loading here...
(OK got it.. pretty cool.)
I've been thinking, reading about photon counting.
Detector efficiency has to be the number one parameter..
(well maybe with time resolution.. short spikey pulses.)

Efficiency times fill factor, right.

Some of the papers are ~1/2 right, and then miss efficiency.

But then they would, wouldn't they?


You've been talking about some photon counting 'white paper'
I hope it has a section on correlated photons.


There's this fact that accidentals go as the flux squared,
and the signal goes as the flux (number of photons.)
So.. given some time resolution, there's an optimal flux..
(signal to noise) that is in between zero and infinity.

Dunno how to quantify that in general, but it's definitely worth
thinking about.

That's OK. I'm sorta thinking about it... there's probably a good paper somewhere.
Here is the classic paper by Aspect etal, it gets everything right...
Some later papers seem confused... but the confusion could be in me. :^)
http://www.lac.u-psud.fr/IMG/pdf/anticorrelation_epl.pdf

Figure 2.

If you run at very low count rates, you get no accidentals, but it takes longer to
get enough counts.. and you also run into the dark counts from your detector.

George H.

Cheers

Phil Hobb


--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC / Hobbs ElectroOptics
Optics, Electro-optics, Photonics, Analog Electronics
Briarcliff Manor NY 10510

http://electrooptical.net
http://hobbs-eo.com