Counting photons with an MPPC

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

Why is your workbench so neat?

It sure is. Gain doubles in roughly a volt.

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.

;)

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.)

I've known women like that.

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

Cheers

Phil Hobbs

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.

Efficiency times fill factor, right.

But then they would, wouldn't they?

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

Cheers

Phil Hobb

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.

On a sunny day (Wed, 21 Aug 2019 18:18:53 -0400) it happened Phil Hobbs wrote in :

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

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

Kiss my grits. ;)

Cheers

Phil Hobbs

On Aug 21, 2019, Phil Hobbs wrote (in article ):

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 wrote in news:qjm351$qla$ snipped-for-privacy@dont-email.me:

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

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

about

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 pr ogram.

Phil Hobbs wrote in news:qjm6cf$e8q$ snipped-for-privacy@dont-email.me:

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

But I never complained...

snipped-for-privacy@gmail.com wrote in news: snipped-for-privacy@googlegroups.com:

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.

On a sunny day (Thu, 22 Aug 2019 08:51:45 -0400) it happened Phil Hobbs wrote in :

A typical example of bandwidth waste, picture is of a static object, only a minuscule scope display has some motion,

AND WE ALL KNOW THERE IS JUST A 555 TIMER AND A POTMETER IN THOSE CLOSED BOXES ;-)

Do not drink so much.