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Re: The Jeffree Cell

PostPosted: Sun Mar 31, 2019 8:43 am
by Harry Dalek
Acousto-optic modulator now this makes sense ...
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By varying the parameters of the acoustic wave, including the amplitude, phase, frequency and polarization, properties of the optical wave may be modulated. The acousto-optic interaction also makes it possible to modulate the optical beam by both temporal and spatial modulation.

A simple method of modulating the optical beam travelling through the acousto-optic device is done by switching the acoustic field on and off. When off the light beam is undiverted, the intensity of light directed at the Bragg diffraction angle is zero. When switched on and Bragg diffraction occurs, the intensity at the Bragg angle increases. So the acousto-optic device is modulating the output along the Bragg diffraction angle, switching it on and off. The device is operated as a modulator by keeping the acoustic wavelength (frequency) fixed and varying the drive power to vary the amount of light in the deflected beam.[9]

There are several limitations associated with the design and performance of acousto-optic modulators. The acousto-optic medium must be designed carefully to provide maximum light intensity in a single diffracted beam. The time taken for the acoustic wave to travel across the diameter of the light beam gives a limitation on the switching speed, and hence limits the modulation bandwidth. The finite velocity of the acoustic wave means the light cannot be fully switched on or off until the acoustic wave has traveled across the light beam. So to increase the bandwidth the light must be focused to a small diameter at the location of the acousto-optic interaction. This minimum focused size of the beam represents the limit for the bandwidth.[/color]

The Harry cell ~! The poor mans Jeffree cell

PostPosted: Sun Mar 31, 2019 4:12 pm
by Harry Dalek
I tried some thing i noticed about the the ultrasonics or supersonic waves in the liquid are more intense moving towards the top of the liquid using this just pointing the laser just below the liquid at an angle you can use this to move the laser beam either side of its center focus and almost cut it out ..
i am not sure this is the true jeffree cell effect or not but would be more or less depending on the voltage to the driver circuit a way you could modulate the driver for a light cell ...i took a few videos which can't all view in video preview or you be loading for ever ..... :shock: but i will post them up for those interested to download .....
I think with the 20 volts voltage to the driver i am using is the best this would do without increasing the voltage ,so would have to look here for a larger cell a way to move more liquid in other words .
Video's i was adjusting the jar kero level mainly with an eye dropper seeing the different levels effect on the laser and its intensity ,same effect i suppose could of been tried with a variable voltage to the driver adjusting the liquid vibration ..so pretty much filmed what i was up to today .
You will notice the laser line light change's in intensity but there's also a change below this line at the laser focal point ,the intensity is brighter to the camera than the eye the light is all most gone to the eye on the line any way

OH the mess of experimenting ! The Harry Cell sorry Jeffree ! :lol:


Re: The Harry cell ~! The poor mans Jeffree cell

PostPosted: Sun Mar 31, 2019 6:16 pm
by Andrew Davie
Harry Dalek wrote:i took a few videos which can't all view in video preview or you be loading for ever ..... :shock:


There is a video format which allows on-the-fly loading and viewing, and is explained somewhere in the forum. In other words it is possible to post videos that do not require you to wait while they load, before you can view them.

Re: The Harry cell ~! The poor mans Jeffree cell

PostPosted: Sun Mar 31, 2019 11:27 pm
by Harry Dalek
Andrew Davie wrote:
Harry Dalek wrote:i took a few videos which can't all view in video preview or you be loading for ever ..... :shock:


There is a video format which allows on-the-fly loading and viewing, and is explained somewhere in the forum. In other words it is possible to post videos that do not require you to wait while they load, before you can view them.

Oh ok Andrew i didn't know that and that would be better , i will have to have a look for it !

Re: The Harry cell ~! The poor mans Jeffree cell

PostPosted: Sun Mar 31, 2019 11:32 pm
by Andrew Davie
Harry Dalek wrote:
Andrew Davie wrote:
Harry Dalek wrote:i took a few videos which can't all view in video preview or you be loading for ever ..... :shock:


There is a video format which allows on-the-fly loading and viewing, and is explained somewhere in the forum. In other words it is possible to post videos that do not require you to wait while they load, before you can view them.

Oh ok Andrew i didn't know that and that would be better , i will have to have a look for it !


viewtopic.php?f=29&t=2299#p21926

Summary: Use software called 'Handbrake' and select 'web optimised'

Re: The Harry cell ~! The poor mans Jeffree cell

PostPosted: Mon Apr 01, 2019 4:16 pm
by Harry Dalek
Andrew Davie wrote:
viewtopic.php?f=29&t=2299#p21926

Summary: Use software called 'Handbrake' and select 'web optimised'


I had a look at handbrake its 64 bit i only have 32bit windows ...if its just resizing videos i can do this with anyvideo converter which i use ...I was looking at the codes in the brackets Andrew do i just use [mdat]link address of the video [mdat] or [mdat][/video] link address of video [/video][mdat]......sorry i am lucky to get this far with codes i am hopeless ! :oops:

Re: The Harry cell ~! The poor mans Jeffree cell

PostPosted: Mon Apr 01, 2019 9:31 pm
by Andrew Davie
Harry Dalek wrote:
Andrew Davie wrote:
https://www.taswegian.com/NBTV/forum/vi ... 299#p21926

Summary: Use software called 'Handbrake' and select 'web optimised'


I had a look at handbrake its 64 bit i only have 32bit windows ...if its just resizing videos i can do this with anyvideo converter which i use ...I was looking at the codes in the brackets Andrew do i just use [mdat]link address of the video [mdat] or [mdat][/video] link address of video [/video][mdat]......sorry i am lucky to get this far with codes i am hopeless ! :oops:


A shame.
There are old versions at https://handbrake.fr/old.php - perhaps one of those will work.
The issue is the file itself must be encoded with the various parts in the correct order. Handbrake does this. It's nothing to do with the forum codes.

Re: The Harry cell ~! The poor mans Jeffree cell

PostPosted: Tue Apr 02, 2019 2:31 pm
by Harry Dalek
Andrew Davie wrote:
A shame.
There are old versions at https://handbrake.fr/old.php - perhaps one of those will work.
The issue is the file itself must be encoded with the various parts in the correct order. Handbrake does this. It's nothing to do with the forum codes.


I down loaded a 32 bit version Andrew its installed i will have a go with that but looks like its just a trial version and only converts a short part of the video ,and does not look like its go a tick box for web there's a convert to webm but couldn't find a tick box for other formats for the web may be its only in the 64 bit version .

Re: The Harry cell ~! The poor mans Jeffree cell

PostPosted: Tue Apr 02, 2019 3:44 pm
by Andrew Davie
Harry Dalek wrote:
Andrew Davie wrote:
A shame.
There are old versions at https://handbrake.fr/old.php - perhaps one of those will work.
The issue is the file itself must be encoded with the various parts in the correct order. Handbrake does this. It's nothing to do with the forum codes.


I down loaded a 32 bit version Andrew its installed i will have a go with that but looks like its just a trail version and only converts a short part of the video ,and does not look like its go a tick box for web there's a convert to webm but couldn't find a tick box for other formats for the web may be its only in the 64 bit version .


Never mind!