60Hz screen refresh optimal?

[Harvey Saayman]

Not unless its power is rectified, but a normal light bulb is connected directly on 220v @ 50Hz (voltage may differ where your from) That means that every 50/1 second the positive and negative switches around(graph looks like a sine wave) causing the bulb to fade in and fade out so to speak... 50 time a second If the power is rectified(like a power supply does), the AC is converted DC(after a transformer steps down the voltage) where the positive and negative stays the same(they don't switch around like AC)

Harvey Saayman - South Africa Junior Developer .Net, C#, SQL

you.suck = (you.passion != Programming)

[dave kelly]

The flicker is caused by the difference in freqencies. ie if the refresh is 60 Hz, and the fluorescent lights are 60 Hz, one will be off by a bit compared to the other, and you get the difference between them as a beat.

[LittleYellowBird]

HarveySaayman wrote:

so then even normal light bulbs bug you as they flicker at a rate of 50Hz??

AFAIK Light bulbs don't flicker because the tungsten element glows all the time even though the current through it is AC. The element does not have time to cool enough between each cycle. Fluorescent tubes do flicker enough to give people headaches so you can get a version that functions at double the normal frequency for work environments (100Hz here in the UK).

HarveySaayman wrote:

the human eye cant "register" more than 30 or 40Hz

You can see higher frequencies than this. If you want to see something flickering try looking slightly to one side of it and 'watch' it out of the corner of your eye. It's your peripheral that can pick up fast movement or flicker. I believe it is a defence mechanism from when we had to watch out for predators sneaking up on us! :)

Ali

[Harvey Saayman]

Alison Pentland wrote:

The element does not have time to cool enough

your absolutely right, i didnt even think of that... I need some more coffee :rolleyes:

Harvey Saayman - South Africa Junior Developer .Net, C#, SQL

you.suck = (you.passion != Programming)

[benjymous]

US power is at 60Hz, so their lightbulbs will flicker at 60.

Help me! I'm turning into a grapefruit! Buzzwords!

[Brady Kelly]

It's Friday, have a beer. :laugh:

A SINGLE-PHOTON TURNSTILE, a device in which photons are emitted one at a time under controlled circumstances, has been created by a team of scientists from Stanford (US), Hamamatsu Photonics (Japan), and NTT (Japan). Essentially the researchers use the quantization of electrical conductance to produce a quantization of photon emission. They put together a quantum well (the frontier between two thin semiconductor layers) containing a single electron (other electrons are dissuaded from entering because of a "Coulomb blockade" effect) with a quantum well containing a lone (comparably Coulomb blockaded) hole, and then cycle the voltage across the whole stack of layers in such a way that the lone electron and lone hole meet, mate, and make a lone photon. The resulting device, which operates at mK temperatures, is typically a tiny post some 700 nm tall and with a diameter of 200-1000 nm. (J. Kim et al., Nature, 11 February 1999.)

[LittleYellowBird]

Absolutely - helps you think straight ;)

Ali

[Brady Kelly]

I doubt it would this early (I have yet to start work), but it's always a nice thought.

A SINGLE-PHOTON TURNSTILE, a device in which photons are emitted one at a time under controlled circumstances, has been created by a team of scientists from Stanford (US), Hamamatsu Photonics (Japan), and NTT (Japan). Essentially the researchers use the quantization of electrical conductance to produce a quantization of photon emission. They put together a quantum well (the frontier between two thin semiconductor layers) containing a single electron (other electrons are dissuaded from entering because of a "Coulomb blockade" effect) with a quantum well containing a lone (comparably Coulomb blockaded) hole, and then cycle the voltage across the whole stack of layers in such a way that the lone electron and lone hole meet, mate, and make a lone photon. The resulting device, which operates at mK temperatures, is typically a tiny post some 700 nm tall and with a diameter of 200-1000 nm. (J. Kim et al., Nature, 11 February 1999.)

[LittleYellowBird]

Sorry to here that. I finish early on a Friday and the sun is shinning (which is a real novelty here in the UK) so I am looking forward to a chilled beer in about 4 hours time ..... :-D I will tell you what .... I will drink one for you too - I am good like that! ;)

Ali

[Brady Kelly]

Please do, thanks. :-D

A SINGLE-PHOTON TURNSTILE, a device in which photons are emitted one at a time under controlled circumstances, has been created by a team of scientists from Stanford (US), Hamamatsu Photonics (Japan), and NTT (Japan). Essentially the researchers use the quantization of electrical conductance to produce a quantization of photon emission. They put together a quantum well (the frontier between two thin semiconductor layers) containing a single electron (other electrons are dissuaded from entering because of a "Coulomb blockade" effect) with a quantum well containing a lone (comparably Coulomb blockaded) hole, and then cycle the voltage across the whole stack of layers in such a way that the lone electron and lone hole meet, mate, and make a lone photon. The resulting device, which operates at mK temperatures, is typically a tiny post some 700 nm tall and with a diameter of 200-1000 nm. (J. Kim et al., Nature, 11 February 1999.)

[Anthony Mushrow]

Alison Pentland wrote:

You can see higher frequencies than this. If you want to see something flickering try looking slightly to one side of it and 'watch' it out of the corner of your eye. It's your peripheral that can pick up fast movement or flicker. I believe it is a defence mechanism from when we had to watch out for predators sneaking up on us!

I noticed that just a few days ago with a TV. I thought it strange. At least now I know I'm not going insane and there's some explanation for it.

My current favourite word is: I'm starting to run out of fav. words!

-SK Genius

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[Lost User]

Ashley van Gerven wrote:

I know 60Hz on a CRT will give you a headache, but what's the general opinion of refresh rates on LCD? Is 60Hz doable?

Just get a carton of Coopers Sparkling Ale and drink while you use it and there will be no problem. Besides that, I have a Chimei 22" 1680 x 1050 and the Missus has a Chimei 19" 1400 x 900 and both run at 60Hz with no dramas.

Michael Martin Australia "I controlled my laughter and simple said "No,I am very busy,so I can't write any code for you". The moment they heard this all the smiling face turned into a sad looking face and one of them farted. So I had to leave the place as soon as possible." - Mr.Prakash One Fine Saturday. 24/04/2004

[El Corazon]

Ashley van Gerven wrote:

Is 60Hz doable?

yes it is doable, and if you have the right monitor.... 1920x1080 is doable at 120Hz as well.

Ashley van Gerven wrote:

I know 60Hz on a CRT will give you a headache

actually, this is right and wrong at the same time. For some, 60hz is a headache, for others 75Hz is. Generally, when one was a headache, before the LCDs entered the market, I would tell people to try the other. Declaring which was which for all people was bad. For a time they switched all monitors to 75hz to help reduce headaches, they simply switched who had the headache making one set happy and another unhappy. The only rule to human behavior is that all rules are "averages" there is someone, somewhere out there to break any rule. :-D

_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb) John Andrew Holmes "It is well to remember that the entire universe, with one trifling exception, is composed of others."

[El Corazon]

HarveySaayman wrote:

AFAIK the human eye cant "register" more than 30 or 40Hz

untrue, untrue... This was once believed to be so, we now know it to be false. The human eye has a tracking range of 30hz to 120hz and maybe beyond. A study of top air-force pilots, the best of the best, shall we say, demonstrated eye-tracking capability on the 120hz range and hand-eye coordination that broke previous estimates as well. The only rule is there are no absolutes. :)

_________________________ Asu no koto o ieba, tenjo de nezumi ga warau. Talk about things of tomorrow and the mice in the ceiling laugh. (Japanese Proverb) John Andrew Holmes "It is well to remember that the entire universe, with one trifling exception, is composed of others."

[Shog9 0]

Normal light bulbs don't bug me. Florescent tubes, i can see the flicker, and give me terrible headaches (though some of that is probably the narrow spectrum).

Citizen 20.1.01

'The question is,' said Humpty Dumpty, 'which is to be master - that's all.'

[Ashley van Gerven]

I think they list it as optimal so you know which option to select in windows. Fonts etc seem to go blurry depending on the refresh rate you select.

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