Lens Disk idea

[Steve Anderson]

If that's the case, fair enough...it's been one heck of a week here so I haven't been able to keep on top of things as I would like to usually...

Steve A.

[AncientBrit]

Not sure how narrow the scan line will appear to the eye.

Most LED lenses diffuse the light from the chip to produce a fairly broad swathe so maybe the scan lines will overlap.

Also a broad "spot" may have an effect on the perceived resolution along the NBTV line.

Regards,

Graham

[Viewmaster]

Well i finished my first go at a finished one the led nipkow..perhaps i should do an Albert and call it the LEDKOW but not using the led part so might be cheating .

.

As LEDs are not used put them last, so KOWLED.......you can led a cow to 12v but you cannot make him glow.

My,my Harry, you certainly do get going when you get going !
Who does all the dusting, cooking, housework and gardening then?

[Harry Dalek]

I will be the first to admit I've only skimmed through the previous, but how do you plan to get power, signal (and perhaps) commutation info to these LEDs? Irrespective of their optical performance. Not being negative, just curious...please don't say slip-rings...

Steve A.

No a camera use idea Steve ....just using the leds casing the clear lens to scan to a solar cell head amp,i have not looked into monitor use ...using a luxeon on the staggered mirror drum it only reflects the tiny leds inside ,i suppose if you dropped the brightness enough perhaps you would just see the same as well off a direct view clear led but yes the commutation would be a problem ....i will stick to the camera idea for now no need for all that this way around

[Harry Dalek]

Steve,

I think he's using them as lenses only, back lit.

No actual signal excitation,

Cheers,

Graham

Yes Graham just an idea i tested and wanted to give it a go all i need it to do is rotate those clear led casings .
An led monitor might work but might be a bit beyond my stills .

[Harry Dalek]

Well i finished my first go at a finished one the led nipkow..perhaps i should do an Albert and call it the LEDKOW but not using the led part so might be cheating .

.

As LEDs are not used put them last, so KOWLED.......you can led a cow to 12v but you cannot make him glow.

My,my Harry, you certainly do get going when you get going !
Who does all the dusting, cooking, housework and gardening then?

I was hoping you would come up with a correct name ! Thats funny i like that Albert

Albert i just did the mowing 4 hours big front back yard fixed my mother inlaws car, put together a flat pack ,and up went the christmas tree for the kids and the house work as well i do the dusting and the vacuuming ! near on 3pm now i have time for bliss NBTV.

[Harry Dalek]

Not sure how narrow the scan line will appear to the eye.

Most LED lenses diffuse the light from the chip to produce a fairly broad swathe so maybe the scan lines will overlap.

Also a broad "spot" may have an effect on the perceived resolution along the NBTV line.

Regards,

Graham

Yes Graham the led is used to diffuse the light for the distance of the led workings to the lens part but seems to at distance light coming from behind it will focus it to a tiny dot which can be adjusted at a focal distance away from the leds lens ...,these are very glass like optically images can be seen very well via them.


Hope lines don't overlap you only have one shot hand drilling ! anycase get some sort of image ..

The flying spot camera i have has to be adjusted for this disk the leds are in the way now so need a rebuild it need a light proof box for a start anyway.

[Harry Dalek]

I had a bit more time today and put my mind to making a light proof case for that Nipkow disk , i like to reuse stuff i have handy as i am no good at making stuff from scratch .
I have reused this little drill bit tool box which i had no use for so i am glad i kept it .
I wanted to work out all the hard stuff today like mounting the lens and working out the placement of the nipkow so happy with the results , might even have room in that case for some electronics .

I just really wanted to reuse the electronics from the last one if i get some nice results i might move them to the case ,any case it will be able to test this new disk and a normal nipkow...

[Harry Dalek]

Well testing out this disk is a bit more work than i was expecting as i have had to really pull to bits the last one and remount it all in this different idea .

Where i am up to is testing the motor and the disk due to it having the leds on it it was really much harder than a flat only Nipkow so they were all clear to move and about the right distance from lens and head amp solar cell ..i suppose i will find out for sure when its all back together .

I have also mounted and tested the encoder and reflective sensor my friend care of gary which has come in handy once again .

I was right a while back on the encoder when i was thinking reflective surface and not so reflective is that worked last time ...as i am using no black this time just reflective gold colour of the dvd and the white paper not so reflective ...so the encoder in my case is working like that not so much the black and white idea ,only pain is i have to cut the encoder disk so the reflective part of the dvd is viewable to the IR sensor.

Heres a few pictures of the work to date ..the motor control is via the case i used for the flying spot scanner...the mechanical sync is via the circuit board you see in the case and the video sync mixer board is there to....

I will post some more when i get more of it back working .

[gary]

I was right a while back on the encoder when i was thinking reflective surface and not so reflective is that worked last time ...as i am using no black this time just reflective gold colour of the dvd and the white paper not so reflective ...so the encoder in my case is working like that not so much the black and white idea ,only pain is i have to cut the encoder disk so the reflective part of the dvd is viewable to the IR sensor.

Well you have done that now and if it works all well a good. The other thing you could have done, and may want to do in future, is to take your encoder print out to somewhere they can do photocopies. For a few cents you can make enough to last you quite a while. The photo copier toner should work the same as laser printer toner. If you do that, it may be a good idea to just get the one copy first just to make sure. I am sure this won't be the last encoder you make .


Edit: I should point out also that for optimum efficiency the reflective sensor should be perpendicular to the encoder, the pictures seem to indicate that you have it at a bit of an angle.

Having said that I am wondering if your arrangement only works at that angle as I would have thought there would have been significant IR reflection from the gold paint on the disk. I am wondering if it works at an angle because the diffusing characteristic of the paper causes some light to be reflected back to the sensor whereas the non-diffusing characteristic of the gold paint causes the reflected light to continue travelling in the same path thus missing the sensor. Stranger things have happened.

Actually Harry, I wonder if you could do me a favour? As I don't have an ink printer any more I can't do the following experiment myself:

I have to admit I find it amazing that a black (ink) surface would reflect IR back at more-or-less the same intensity as the white surface of the paper. Being from Missouri I would like to "see" that effect - one way to do it is to video the encoder at the point that the sensor is shining on it with a webcam (or similar). As these cameras are IR sensitive we should see a spot of light that does not diminish in intensity when it is on a black section to when it is on a white section. In fact, if you video it in a dark room that has no source of visible light we should see that the encoder pattern looks all white instead of black and white.

You could also perform the experiment with any black and white print out from your printer and using your TV remote control as the the IR source - in fact that would obviously be much easier.

If you don't have time for that I wonder if you could post me a copy of one of your encoders? Possibly with the Christmas card you were going to send me?

[Harry Dalek]

Hi gary

Well you have done that now and if it works all well a good.

It worked right away i was expecting the surface reflective power to match what i tried last time with out worrying to much not having black.

The other thing you could have done, and may want to do in future, is to take your encoder print out to somewhere they can do photocopies. For a few cents you can make enough to last you quite a while. The photo copier toner should work the same as laser printer toner. If you do that, it may be a good idea to just get the one copy first just to make sure. I am sure this won't be the last encoder you make .

Yes the only problem i found last time and i should think will happen this time is the slight pulse changes in how i cut them out will cause the lines to not match up 100% a sine wave effect at best or ragged if i have messed up.
I must admit i would rather not have to cut it and just use one with the correct ink for sure .

Edit: I should point out also that for optimum efficiency the reflective sensor should be perpendicular to the encoder, the pictures seem to indicate that you have it at a bit of an angle.

I sort tried this to have the sensor fit in the case when closed it one of those things i agree rather have it the way you think ,i rather not cut the plastic for the screw adjustment and see how it gos.

Having said that I am wondering if your arrangement only works at that angle as I would have thought there would have been significant IR reflection from the gold paint on the disk. I am wondering if it works at an angle because the diffusing characteristic of the paper causes some light to be reflected back to the sensor whereas the non-diffusing characteristic of the gold paint causes the reflected light to continue travelling in the same path thus missing the sensor. Stranger things have happened.

I had it upright to start with just looked like it was poking up to much so i adjusted it at the angle and still seemed to work fine ...the reflective surface seems about the same distance as last time ....perhaps because it reflects better its a bit further away than a black and white paper one can do ..but what you think may very well happen i don't know .

Actually Harry, I wonder if you could do me a favour? As I don't have an ink printer any more I can't do the following experiment myself:

Sure lets see

I have to admit I find it amazing that a black (ink) surface would reflect IR back at more-or-less the same intensity as the white surface of the paper.

I just think of it like being reflected back if via glass and then via a non shiny paper there would be a big difference so a on off pulse ...i was going to cut out the white of the paper and leave the black and see if that was better but this worked .

Being from Missouri I would like to "see" that effect - one way to do it is to video the encoder at the point that the sensor is shining on it with a webcam (or similar). As these cameras are IR sensitive we should see a spot of light that does not diminish in intensity when it is on a black section to when it is on a white section. In fact, if you video it in a dark room that has no source of visible light we should see that the encoder pattern looks all white instead of black and white.

Oh yes i like that the cameras and see the IR led light you want to see the reflection on the current encoder idea i can do that as soon as i get the kids to bed tonight.
Oh your from Missouri ?
Missouri —nicknamed The Show Me State !

You could also perform the experiment with any black and white print out from your printer and using your TV remote control as the the IR source - in fact that would obviously be much easier.

Oh i suppose its no different to the reflective sensor i will look into that just see if my camera sees it first .

If you don't have time for that I wonder if you could post me a copy of one of your encoders? Possibly with the Christmas card you were going to send me?

You want just want the cut out encoder and dvd as i do stuck to it ,i think i could manage that and a christmas card for sure

[gary]

Sorry Harry, I meant a normal encoder - one with black and white segments - not the one with the cutouts - although that would be interesting too - I just want to convince myself that your printer ink is reflective to IR

[Harry Dalek]

Sorry Harry, I meant a normal encoder - one with black and white segments - not the one with the cutouts - although that would be interesting too - I just want to convince myself that your printer ink is reflective to IR

Hi Gary

I just did an experiment using a remote controls IR led ...i tried the normal print out and my last black cd cut out side by side ...the results are as we think ...
The black ink and the white paper reflect i think about the same poor...the cut out cd very shape reflection and nothing i can see from the white paper so i can see why i was getting no results from the print out and the cut encoder worked so well ...
i will drop the video size and up load so you can see ...your experiment is great i can use this to test other inks and such !

[Harry Dalek]

Theres the IR light reflection tests Garys very good idea ...
The 61 is just the cut out encoder and the 64 the print out along side the cut out one you can see why one worked the other didn't.

[M3DVQ]

couple of quick and dirty photos to demonstrate the problem:
The subject is an inkjet photocopy of some university notes (just the first inkjet print I could lay my hands on)

First infra-red and visible light:


Then most of the visible light filtered out:


The little bits of text still visible will be red ink I suspect - my "visible light filter" was just a 3.5" floppy disk so not perfect

The first photo looks bleached out because there is no ir filter in the camera. Apologies for the poor resolution and bad focus too, it's a 10 year old webcam that's been abused a lot!