With trepidation I attempted to remove the AG layer on my Benq FP531 panel last night.

Well. . . . First I should say I started my project roughly a year ago and with a new startup business and a new baby in February. . . . I am just now almost complete. I am now regretting attempting the AG removal. . . . mostly because it has proven to be a royal pain and because once everything is finally up and running I will not ever have a full appreciation of the benefit because I will not have a 'before and after'.

back to the reason for my post. . . . I nearly completed the process of removing the AG layer using the rag method when a piece of very sticky tape affixed to the polarized layer and when I removed the tape. . . off came a bit of the polarized layer. In frustration I have now removed the entire polarized layer. I obviously now need to replace the polarized layer and need some help. What to buy? Where to buy? I have found SIMUL8RS 'Indexed' thread helpful and found the link to polarization.com. Looks like this guy is pushing the Linear Polarizer Super-High Contrast No Adhesive product and if this is what I need . . . all do it but OUCH. . . It will cost me $75.00. Is there a better way and is there a cheaper way?

My last step aside from having to reaffix a polarized layer is to build my lense sled today. I am bummed because I thought I might be able to fire this thing up this weekend. . .. . but now the polarizer problem.

Try 3dlens.com http://3dlens.com/shop/polarizer.php

Thanks for the suggestion SIMUL8R but it appears they require a purchase of no less that 10 units. Has anayone been able to order just enough to fit a 15" panel? Am I correct in my understand that it is best to get a polarizer sheet without adhesive?

No you can get 1 piece .. as the lot number changes so does the price. 10 is the min amount you need to get the lot discount ... (btw I didnt buy from them before - I am guessing this is how it works - I was gonna get fresnels from them)

You may be able to just get enough for just the polar that you need to replace but you have to determine the degree your current polar actually polarizes against the otherside polar on your panel and match it up to 3dlens's film with the same degree (hopefully). Meaning if yours polarizes as 90 degrees and 3dlens does as well then your set with just 1 film.

As far as with or without adhesive. Unfortunately I can't provide you an experience opinion on this. Sandwiching the lcd substrate with adhesed polar provides little more of a transmissive panel IMHO as I've read in a previous link and being able to do this on your own and in correct angle to the other polar could be difficult but has been done by a member here as I recall, not to mention the issues of having artifacts laminated in between (lint free environment). Recently Elken2004 on the other hand as made claim that unlamenting and locating the polar at the triplet and collimating fresnel can be done but so far I've read a couple of members have found some issue when doing this.

My suggestion.....since you already ruined one polar then find it's angle of polarizing to your other polar on your panel. Match it up to 3dlens (not adhesive) and proceed to find the area that Elken found either butted up to your lcd or within the area of your collimating fresnel (this seems to be a little more foregiving for a good fix). The ultimate choice if you don't want to mess around with this is to send your panel to a special professional lcd lamenting business and have them deal with it.

Wow. . . I did not realize this was as big of a deal as it apprarently is. I have now read for hours the discussions and have yet to come accross someone who has been successful with replacing the polarizer with acceptable results. Do you have a suggestion on a 'professional lcd lamenating business'? Would it be better cheaper to start with a new panel? If so. . . I sure hope I can find the same monitor because I have already installed the electronics and extended the control wires. . . . Here is a link to my PLOG not all my work is as shabby as my attempt to remove the AG!

Hi,

Sorry to hear of your troubles.


Several people have had success with non adhesive polarizer replacement.

Polarization.com's Super-High Contrast polarizer is superior to the 3dlens.com product. I have researched it to be the single best polarizer available -let alone to buy as a consumer. It is truly outstanding that polarization.com chose it to sell, as they are the only source I could find beyond bulk manufacturer orders.

Bear in mind there is no anti-glare on that polarizer from polarization.com, so the job is already done. Plus it is just cool to be able to point at another component inside your projector.

Friend: "What's that?"

You: "Oh that? That's the polarizer. It is critical to the function of the unit."



If you would like (and don't mind a reversed image and some artifacts) you can clean up your old polarizer (that you peeled off the glass substrate) and place the largest clean area over your triplet. Then flip your panel around. This could at least let you fire it up. By keeping the dodgy polarizer away from the focal plain (the LCD) any blemishes will at least fall out of focus. If your panel or software can reverse the image then it could make for a decent long term solution. I suppose you could also project into a mirror.

You do not want an adhesive polarizer. That would be trouble. I cannot imagine anyone applying one of those without bubbles and dust.

Hey, your projector looks great by the way .

Mark

Mark-

Thanks for your response. . . . I am encouraged. I was pretty frustrated. Do I understand you correctly that this is not a half ass solution? The reason I ask is at $75.00 plus shipping. . . I am half way to another panel. I am happy to do it so long as I will still have a first rate projector. If so. . . Polarization.com's Super-High Contrast polarizer it is. I will place my order Monday. Sounds like I will have enough left over for another 15" panel if anyone is interested.


Thanks for your compliment!

Trevor (a.beam.reach)

Mark-

Do you know who might be able to give me some guidance on lens placement. . .. Sounds like the collimator lens needs to be pushed back. . .. How far? Do I place the new polarizer against the LCD or back it off a bit? Any pictures available of a successful lens configuration.

Thanks ahead of time,

a.beam.reach

Unfortunately, it is complicated -hence the enormous anti glare thread . It isn't guaranteed. Odds are you will have nothing but a gain in quality -but those are just the odds:

There is a possibility that your original polarizer contained a layer of Birefringent material that worked to correct a phase shift in your LCD's Birefringent Liquid Quartz. In which case I have hypothesized you may see a loss of contrast in your monitor. Those that have done the replacement have not had this problem so far, so they either have panels with no Birefringent compensation, or only their rear polarizer had it added. It is documented that some panels have compensation built into their front polarizers. If your panel is one of those, and my hypothesis is correct, you will loose contrast. Odds are, based on others experiments, that your panel has just a plain old polarizer and any fully linear (zero Birefringence) polarizer will do the trick. The polarization.com polarizer is one of these.

The Super-High contrast polarizer is likely of a higher quality than the one you removed. It likely has both a higher transmittance and contrast. It is reserved by manufacturers to give an edge to their high end monitors. There are also some heat advantages to removal as mentioned later.

However, there is a disadvantage to using a replacement polarizer. It will not be adhered to your panel. This will introduce around a 5% loss in transmittance as light must now pass over 2 more air to plastic interfaces. This transmittance drop will translate into around a 5% loss of brightness. If your panel is not high end, it is possible that the improved quality of the polarizer will make up for this. Of note: People have not noticed any change in brightness who have made the replacement. At least as I recall.

The big advantage is of course that this replacement has no anti-glare. That is huge. And when removing the anti-glare you are left with a delicate exposed PVA layer. The replacement polarizer has this protected nicely.
If you do decide to get the replacement polarizer you must bear in mind the orientation of the original polarizer. That is, the polarizer has an axis of orientation. It will only work if placed on your panel with the same orientation as the original. So be sure the size of polarizer you purchase can rotate to any orientation on your panel and still fit (like at 45 degrees). Chances are, you will use the whole sheet for just one panel due to an awkward axis.

Correct. By removing the anti-glare you are losing the diffusion that cuts down on Fresnel details (Grooves) being projected. This occurs any time you remove the anti-glare, not just with polarizer replacement. People add around 5mm with success as I recall.

As long as there is nothing between the panel and the polarizer you can place it wherever you want. I would suggest you place it up against the Fresnel (if it is not too hot). That way your panel will have cool air passing directly over the glass and will not pick up heat off the polarizer. That is a nice advantage to removal as the polarizer insulates the panel normally and the polarizer itself converts 50% of the light that enters to heat.

I don't remember seeing any.

Mark

Mark-

THANK YOU. . . . THANK YOU. . . . THANK YOU! There is hope!

I will let you know the results.

Trevor (a.beam.reach)

If it's not too late to throw in my two cents...

I've used the high contrast polarizer from Polarization.com, and also the cheaper version they have (which comes rolled up). The cheaper version I really couldn't recommend, but the high contrast one is fine.

I used it on a 15" Benq FP567s. I just gaffer taped it to the frame that holds the lcd panel, which left a gap of about three or four millimeters between surfaces. That's the sort of placement I'd suggest.

I can't honestly say whether it's better or worse than the original polarizer in terms of image quality, but that sort of says to me that it must be pretty good then, if you know what I mean.

I'd send you what I have left over, but I'm in Australia, and I don't think there'd be enough to cover another panel anyway (only falling short by a frustrating centimetre or so).

All I did to figure out the cutting angles was look through the polarizer at the lcd panel. When you can see through both, you've got the angles you need to keep them at (it'll probably be 45 degrees).

Anyway, good luck with it.

Les.

Thanks Les! I ordered the high contrast polarizer last night. Your comments confirm that I made the right move as it is consistent with Mark's post. I appreciate your 'two cents.'

Now. . . . Do you place the polarizer on the triplet side (front of panel where the old one came off) or on the lamp side (back of panel) or does it matter?

Thanks,

Trevor

As mentioned, the polarizers must be on opposite sides of the panel. There are 2 polarizers on every panel. You only removed the one from the front side.

Why did your anti-glare face the triplet? Be sure your panel isn't backwards.

Mark

Mark-

I hesitate to write about my foolishness. . . . but I figure you already know. Yes, I was planning to mount my panel backyards. I read in the guide, "Because the optics invert the image on the LCD panel, the panel will be mounted upside down and flipped from left to right." In my mind I not only flipped the panel upside down . . . . but turned the panel backyards as well. . . I guess the "flipped from left to right" statement threw me a bit.

Fortunately I only did all of this in my mind and I will execute it correctly this week. Now that I think about it and the science behind it. . . . it makes perfect sense. Now that the whole community knows I'm an idiot. . . hopefully someday I will come up with something really smart that redeems me.

Thanks,

Trevor

heheheh you just did

also dont forget to throw tameone a bone too !!! he likes them

Thanks elken2004! Bone finally thrown . . I missed throwing it in all my frustration! I was just about ready to torch my project 2 nights ago!

Actually.. . . I owe kudos to the whole community. . . I have been reading for months and months gathering ideas from some real bright folks. . .. . Thanks to all!

I hope to be able to contribute back in time.

Trevor

I placed an order from polarization.com yesterday too, so we will have two more guinea piggy photo's. My front polar is still attached, so i will be able to do before & after pics on a panel with a not so fantastic contrast ratio .

Looking forward to your experiences as well a.beam.reach,
Your PJ looks fantastic! Dead sexy.

Sim, Mark, elken,
Should we post results in here when they come in, or is there a better existing

yoshuapawn-

Here is to successful guinea piggy photos! and. . . . a quick shipment form polarization.com!

Thanks for your compliment on my box.. . . I did some looking at your PJ with the LUMENLAB logo on the top. . . . In a word. . .. AWESOME. Was the logo idea MAC inspired? From the Apple logo on your Powerbook? I am a MAC guy as well. . . would not have it any other way!


Trevor

this looks like a good spot for results

http://www.lumenlab.com/forums/index.php?s...c=15700&hl=

Hey! Guys your not alone...

I did a removal of the AG alright! The Polarizer came with it which I had no idea until I tried the panel.
Just to say! I ordered the Super-High Contrast No Adhesive aswell.
Hopefully this works!

Good luck to you both!

Sorry to hear of your trouble A.K.A. The good news is it sounds like we will be able to fix the problem! Make sure to post your results here

Trevor

Yes, It really looks that way if this works. I'll post results for sure.
Patiently waiting.

My polarizer arrived today. . .. I plan to install the lenses this weekend and will add the polarizer to the mix.. . . I hope to be able to post some screen shots by the end of the weekend.

BUT. . . . One thing is for sure I will be quite methodic about it all and if that means it takes a whole extra week. . . . so be it. I want to do it right and with no more costly mistakes!

Now. . . . so long as I keep repeating my last statement over and over it may actually happen.

Trevor

Hey! a.beam.reach

Did the polarizer do the job? I Still didn't received mine. It was resent due to non delivered to my address.
wrong courrier. This was last week. So I'm still waiting as we speak for this thing. I was just wondering if you had a chance of trying yours yet? Hopefully it's working ok!

Later

a.k.a

a.k.a -

YES! The polarizer worked well. . . . VERY Well! In my case, I determined that the polarizer needed to be cut at exactly 45 degrees. I affixed it with masking tape to the wood frame arround the lcd panel. The frame is 3/4" wide so the polarizer sits 5/16" off the panel and it works quite well. I will post pictures of the results as soon as possible here. I got my projector fired up the day after Thanksgiving . .. . and we enjoyed our first movie (The world's fastest Indian). I have some keystoning tweaking to do but I am very happy with the initial results!

HOPE YOU GET YOUR POLARIZER SOON. . . . Let us know your results.

Trevor

Well I'm happy it work!

You just made my night! Now I can't wait... Hopefully I'll get mine by the end of this week,
can't wait to see some of your results. I'll post any new changes as soon as I can.

John

Quick question? a.beam.reach

How did you manage to figure out the placement of the polarizer?
I just received mine at work today. So hopefully I can figure out the angle. I'll check it out tonight.
I'll keep you guys posted.

later

a.k.a

a.k.a-

Glad to hear you got your polarizer! Here is what I did to figure the placement. . .. I turned on the lcd, shined a flashlight thru and placed the polarizer on the panel. I rotated the polarizer until the image was the most most clear and crisp. For me there was not a dramatic difference between say 40 and 50 degrees but I assumed that the precise measurement must be 45 degrees. To cut it. . . I placed my panel (in my wood frame) down on the polarizer and put a square with a 45 angle along side. I just used the wood frame of my panel as a guide and cut the polarizer with a razor blade.

Picture is NOT to scale.


I hope this helps. . . . Good luck to you. . . . MEASURE TWICE CUT ONCE!

Trevor (a.beam.reach)

Thanks for the quick reply!

Great, tonight is the night. Yes! measure twice and cut once can't argue with that.
Thanks again

a.k.a

beam, just out of curiosity did you try 90 degrees? Elken seemed to have gotten best results at this angle but it was one sheet of the High Contrast Polar coupled and crossed with a lesser one from 3dLens. Also, was this piece you replaced stuck or butted up to the lcd and did you find and 'glowie' issues?

SIMUL8R-

I rotated the polarizer a full 360º with the panel on. . .. . There was no question that 45º offered the best results with my panel. My replacement piece is affixed to my LCD frame which is 3/4" wide with a 1/8" groove for the panel so the polarizer sits 5/16" off the panel . Zero 'glowie' issues to report. I will try and post pictures tonight that validate my assertions.

Thanks,

Trevor (a.beam.reach)

Thanks Trevor. Since you have some spare porlars of this high contrast type, can you cross 2 samples of these together using a light source behind the 2 just to see if they block light at 45 or 90 degrees.

Greatly appreciate it.

They will most definately only completely block light at 90 degrees to each other. SIM, where exactly is this 45 degree thing coming from? I have heard this in a few places now. At 45 degrees you will have exactly 50% of the maximum brightness.

Mark