Mitsubishi 2007 (and possibility '06 & '08) lens cleaning procedure. No more halo's. - Page 8 - AVS Forum
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post #211 of 388 Old 01-07-2011, 08:32 AM
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Quote:
Originally Posted by TempeDuck View Post

The model number is WD-62827.

4. I don't know where to get he total number of hours, but it is on for about 6 hrs or so a day. For the last 6 months...so if i multiple that out it should be 1080 hours.

If your Mits DLP is like mine, you can find the operating hours by pressing the TV MENU button on the remote (the setup menu) and then entering 2470 on the keypad.

I believe the display lists the total number of hours plus number of hours from each recent reset. Be careful you don't do a reset from this menu unless you intend to do so.
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post #212 of 388 Old 01-10-2011, 03:35 PM
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Quote:
Originally Posted by Doug40 View Post

If your Mits DLP is like mine, you can find the operating hours by pressing the TV MENU button on the remote (the setup menu) and then entering 2470 on the keypad.

I believe the display lists the total number of hours plus number of hours from each recent reset. Be careful you don't do a reset from this menu unless you intend to do so.

That worked to pull up a menu but nothing was labeled hours.

Here are pictures of the test patterns:







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post #213 of 388 Old 01-11-2011, 04:42 AM - Thread Starter
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Thanks for the screen shots.

The 'hours' is towards the bottom left. Try menu-2457 if it isn't there. (DON'T hit enter when you enter that screen, toggle down away from "Initialize"!)

Unless you know someone that has done more than light engine swaps, the only solution I can see is a LE swap out.
It could be the DMD itself, a driver board for the device or possibility some adjustment, maybe for the color wheel, but I doubt it.

Did this do this all of a sudden, or was it gradual?

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post #214 of 388 Old 01-12-2011, 02:04 PM
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Quote:
Originally Posted by videobruce View Post

Thanks for the screen shots.

The 'hours' is towards the bottom left. Try menu-2457 if it isn't there. (DON'T hit enter when you enter that screen, toggle down away from "Initialize"!)

Unless you know someone that has done more than light engine swaps, the only solution I can see is a LE swap out.
It could be the DMD itself, a driver board for the device or possibility some adjustment, maybe for the color wheel, but I doubt it.

Did this do this all of a sudden, or was it gradual?


2457 pulled up the test images, I used 2570 and see the screen you describe. The number in the bottom left is 13285. That seems a bit high, I never reset it once I replaced the bulb 6 months ago.

What is the cost associated with an LE swap? Your guide for lens cleaning couldn't do anything would it?
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post #215 of 388 Old 01-13-2011, 04:08 AM - Thread Starter
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Cleaning surely doesn't seem to be the issue.
Replacement costs were discussed a year ago;
http://www.avsforum.com/avs-vb/showt...t#post17718244

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post #216 of 388 Old 01-13-2011, 05:43 AM - Thread Starter
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Also for general reference, here is a 'Archived' Mits thread;
http://archive2.avsforum.com/avs-vb/...6&page=2&pp=30

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post #217 of 388 Old 01-23-2011, 08:12 AM
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Quote:
Originally Posted by TempeDuck View Post

I am having an issue with color gradients on my WD-62827. Would this tutorial fix the issue I am having. I have attached 3 pictures of examples of the issue. I replaced the bulb about 6 months ago due to it going out at the time I had this same issue. Once I replaced it, the issue went away. It has gradually came back since then and now has got to a point where it is almost unbearable.

If this guide won't fix it can you point me in the right direction.

Thanks.



Here the ocean should be a gradual blue color not the abrupt change.



Here the background color should all be one color or a slight gradient.



Here you can see the discoloration on the actors head.

I have a WD-65734 that I can recite the taking apart of every component in it, slightly different then the unit in the OPs thread but similar in many ways.

I once had this happen o my unit when there was a brown out in the building. The TV was on and this happened.

on the menu I went to the ISF calibration #60, IDL, mine is at 37 for a perfect blend of gradients in the colors.
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post #218 of 388 Old 01-23-2011, 08:20 AM - Thread Starter
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One single setting corrected all of that??

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post #219 of 388 Old 01-23-2011, 08:37 AM
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Quote:
Originally Posted by videobruce View Post

One single setting corrected all of that??

Yes, I bought my TV back in 2007 and since then I had the DMD board replaced and a light engine due to the color wheel bearing grinding during shut down, ever since I am still on original bulb with thousands of hours.

I will be ordering a new one soon.

But once my TV did what he is showing I knew right away what setting i can adjust to fix it since I have been in and out of the menus and finding out exactly what they do.

matter of fact I was reading this thread today and noticed that the set you posted and mine are slightly different as the WD65734 doesn't have the LE adjustments for geometry external to the LE and the optical lens that gets taken off to clean the internal lens, well they loctite the 3 screws on.


Here are 2 pictures I just took with it reduced to a lower number which messes up the gradients and then back to 37.
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post #220 of 388 Old 01-23-2011, 08:53 AM
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I have cleaned this unit in and out taking all the components out and reassembling the unit again. I think Mitsubishi went with a more fool proof design later on as it doesn't have the external geometry adjustments.

These pictures show the WD-65734 with the front screen off and shows the Mirror at the back panel, this was hazy before cleaning.

Another picture shows the wiring to the LE on this unit. Big Ferrite goes to the Bulb power board, inside where the board is there are 2 more smaller Ferrites which I did use electrical take. actually I used it on the large and small ferrites and the loud whine noise that sounds like a ballast going bad is gone.

Picture 153 shows the LE part number, how dirty that first fan gets and the rest of the wiring.
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post #221 of 388 Old 01-25-2011, 11:09 PM
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Quote:
Originally Posted by videobruce View Post

One single setting corrected all of that??

Not sure what "IDL" is on that setting, but I had a similar issue with a Runco FP after a firmware update. I called tech. support and they knew right away what it was after I described the problems. It was the color wheel delay or color wheel timing setting. I imagine this is the same thing.
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post #222 of 388 Old 02-13-2011, 05:31 AM
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Has anyone used a LensPen to clean the residue from the projection lens? They look like the ideal tool to remove finger prints from lens, but from earlier reports it sounds like the residue may be more stubborn.
http://www.lenspen.com

Can someone give me an estimate of how long this might take (assuming that that you have done it once before)?

Several times a week I am reminded how terrible my set looks, but haven't had the time/ambition to do it. Maybe it will be a summer project.
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post #223 of 388 Old 02-14-2011, 06:44 AM
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Doug40...
I performed this cleaning on my 4 year old WD57732 this weekend. My bulb blew Thursday night so I thought it was the perfect time. It was my first time to do it. It took me about 2 hours. I took my time making sure I didn't break anything or lose any pieces. My inner lens had a terrible film on it. It looked like a big greasy thumb print. I cleaned it with a Zeiss pre-moistened lens wipe. It took a few wipes to get everything off and leave a clean, lint-free surface. I wasn't rubbing too hard. You can't really without risking damage to the iris anyway. My picture looks amazing now. It's brighter of course with the new bulb but the clarity is infinitely better than it's been in a long time, maybe ever. I forgot how good the TV could actually look. I'll post some pictures as soon as I get them on the computer.

Thanks videobruce!!!

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post #224 of 388 Old 02-14-2011, 01:13 PM
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My wife actually sent me a text today saying how amazing the TV looked and that she liked my skills. It takes a lot to impress her so that shows you just how much of a difference it makes! She said it was crazy clear.

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post #225 of 388 Old 02-15-2011, 06:23 AM
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Quote:
Originally Posted by agthad View Post

Doug40...
I performed this cleaning on my 4 year old WD57732 this weekend. My bulb blew Thursday night so I thought it was the perfect time. It was my first time to do it. It took me about 2 hours. I took my time making sure I didn't break anything or lose any pieces.

Thanks for the info on fixing your set. That means I should get it done in a day or so (I'm terribly slow).
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post #226 of 388 Old 02-21-2011, 08:21 AM
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After following this thread since shortly after it began, I finally had the ambition to clean the lens in my WD-52628. As others have reported, the results were astonding.
The '06 model sets listed above have a different LE removal procedure from those documented earlier. The photos below snipped from a Mits Service manual show the process.

The five photos attached show the back of my set with the LE section shown and 4 images showing connectors to disassemble.

This will continue in the next post.
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post #227 of 388 Old 02-21-2011, 08:36 AM
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Continue removing connectors shown in the pictures below.

In step 9 remove the two screws indicated and loosen the large screw as it may be necessary to rotate the bracket to get the LE around the post. I removed the large screw to remove the bracket before I read the caution about removing the screw that appeared later in the process. The nut behind it may come loose. You can replace it once the LE is on the bench, but it has to be in place when you put it in because the manual says that you can't replace it without removing the LE. I didn't verify it, but it is something to be aware of.

In step 11 (on the picture) I did not need to remove J3
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post #228 of 388 Old 02-21-2011, 08:42 AM
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At this point, you can remove the LE from the cabinet. Bundle the cables and PC board at the left edge of the opening to remove the LE. I found that the LE was stuck in place, but there were no other fasteners to remove. after a few tugs and a prying motion, it broke loose.

Remove the foam cushion around the projection lens.

I depended on the excellent photos by VIDEOBRUCE at the start of the thread. This LE is different, but there are enough similarities.

The next step is to remove the lens from the LE. IMPORTANT: read BEFORE removing the lens.
The Lens is held to the LE by 3 screws; two on top and one under the mirror assembly.
BEFORE you remove the two top screws, photograph them and/or mark their position by scribing the housing so you can get the lens close to the position is was originally mounted. The holes are elongated and there is a lot of movement possible. Too much movement and your alighment task will be made more difficult (and maybe even impossible) once you get it back together.

You might want to tighten the top screws initially to freshen the imprint they make on the lens housing as they will be needed during reassembly.

Ths bottom screw is difficult to access. You will need a slender philips screwdriver with a 5 3/8 inch shank (min) to remove the screw. I didn't have one, so I ended up making one out of a piece of heavy wire from a 5 gallon bucket handle. I flattened the end with a hammer and ground it to fit one of the screws that I removed from the top (I wasn't smart enough to note the position of the screws before I removed the screws).

Once you have removed the 3 screws, the lens assembly can easily be removed from the LE. Note that there is a rubber dust gasket around the base of the lens because of the large clearance between the LE and the lens.

I hung a damp cloth over the opening to the MD chip to keep out dust that might be stirred up in the process.

I found the typical film shown in the photos at the beginning of the thread. It took me a while to get the right light on the lens to see the film, but there was a lot of and it was tough to remove.

I used a lens cleaning solution and lens tissues to lightly scrub the film off the lens. I must have made 6 or more passes with as many tissues. When it was clean, I used a microfiber cloth to polish the surface of the lens.

There is no iris to get in the way on this lens. The lens consists of two major lens and they can be separated by removing 4 small philips screws. I found the inner lens surface to be very clean, although I cleaned it anyway. Once the lens is separated, you can see the mirror. I happened to see a small particle on the surface of the mirror, so I used the microfiber cloth to pick it up with just the lightest touch with a corner of the cloth. If this is like camera mirrors, it is front-silvered and delicate; I was happy not to go any farther with it.
Once the lens is clean, make every effort to get it on the LE in the same position as before.

Before you put the LE back in the cabinet. Look at the alignment screws that are on the front of the LE under the plate. There are 3 hex studs that need a 4 mm socket to engage them and a 5 mm hex nut that needs a hex stud to loosen/tighten it. These are accessable from the front of the set.

Even if you are careful, the LE will likely to bave to be aligned after you put it back in place. The image on mine went up-hill from left to right a few degrees. It might have been acceptable, but it was noticable.
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post #229 of 388 Old 02-21-2011, 08:42 AM
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Reverse the disassembly sequence to put the LE back in the chassis. Do not tighten the large screw on the bracket at the outboard edge of the LE if you are going to align the LE to the screen.

The LE alignment adjustments are accessed from the front panel of the set. On my 52 inch set, you have to remove the speaker bezel below the screen by pulling on it (with care) to free the spring clips. Once the bezel is removed, remove the card reader that is held in place by two screws and pull it out of the opening. At this point you can easily see the adjustments.

I used a 5 mm hex stud on a long shaft to loosen the screw that frees up the platform to move. Also, loosen the large screw on the outboard side of the LE (see photos). I used a 4mm 1/4 inch drive socket on a long extension to turn the hex studs that move the platform.

See the photos for the instructions for putting the test pattern on the screen. The goal of this allignment is to get the pattern square and level on the screen. See the first posts in the thread by VideoBruce to see the effects of the various adjustments. Dont worry about the direction to turn the screws. Turn a screw and look for changes in real time.

Once the pattern is square and level, the LE adjustment lock screws can be tightened.

The pattern will be centered on the screen using electrical adjustments from the remote control as shown in the attached photo about electrical centering.

I use my set as a PC monitor at times, so I set the vert/horiz centering so I can don't cover up any desktop controls if I happen to be using the set at the std 720 or 1080 resolutions top display a Windows desktop.

In the weeks/months before I started, I read the whole thread at least once and reviewed the top posts immediately before starting. It took me the better part of the day to get back to the point where we could watch a DVD the same day, even though the alignment didn't happen until the next day.

I can't thank VideoBruce and others enough for their help in making this repair possible.
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post #230 of 388 Old 02-21-2011, 08:47 AM - Thread Starter
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Nice addition.
I was wondering if you could enlarge some of those photos similar to the size of the 1st attachment?

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post #231 of 388 Old 02-21-2011, 10:48 AM
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I got the clips by using the snipping tool in Windows to snip a portion of the screen. I could have made the service manual PDF larger before I snipped the images, but I didn't think much about it at the time.

Given that they are only a guide to show the approximate location of each connector, they may prove adequate, especially since each connector is stamped with the designator and there are only a few in each location. I'll look at it on another smaller display and see if they still appear good enough. If not, I'll replace some of them.

And again, thanks for starting the ball rolling on this critical repair.
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post #232 of 388 Old 02-21-2011, 11:07 AM - Thread Starter
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I thought these were pics you took.

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post #233 of 388 Old 02-27-2011, 08:37 PM
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After a week's time of watching the picture viewed through the newly cleaned lens in my WD-52628, I am still impressed with the improvement in contrast and brightness in the picture. We moved the brightness and contrast settings back to mid-range or below, where they were when we got the set in early 2006.

Unfortunately, when there is a black screen, the light area to the left of center (as seen in my post of Nov 21, 2010) is still present. It's only noticable in very dark scenes, but is still distracting.

Since the iris is positioned behind the lens assembly that I cleaned and just in front of the mirror, maybe there is something deposited from the iris assembly on the mirror or the lens in front of the mirror that I didn't bother to clean. Given the delicacy of the mirror and the major improvement of the recent lens cleaning, it is going to stay that way until it dies, or the lens needs to be cleaned again.
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post #234 of 388 Old 03-16-2011, 08:50 PM
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Just did this on my WD-57831, looking soo much better now, Thanks Bruce.

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post #235 of 388 Old 03-17-2011, 10:41 AM - Thread Starter
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Doug40; Is during daytime or at night? if at night, is there a lamp in front of the screen? It looks like a internal reflection from an exterior source.

Tspeer; Glad I could help.

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post #236 of 388 Old 03-17-2011, 12:52 PM
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Yet another satisfied customer here. Just cleaned a 65732...awesome instructions and pics! This guy deserves a round of applause! Thank you very much.
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post #237 of 388 Old 03-21-2011, 11:52 AM
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Quote:
Originally Posted by videobruce View Post

Doug40; Is during daytime or at night? if at night, is there a lamp in front of the screen? It looks like a internal reflection from an exterior source.

The light part of the screen is evident in a dark room. It is definitely coming from within the set, but given the improvement, it seems like it couldn't be another filmy surface like the one I cleaned. If I remember correctly, there was one report earlier in the thread where the writer cleaned the lens above the chip and later found another surface that was covered with a film when there was still evidence of light scattering.

If there was a film on the mirror, and if it was heavier on one portion of the mirror, then that might account for the light spot. There is an iris that is just above the mirror that might account for an uneven deposit on the mirror, but I didn't pay any attention to it since I didn't think it was involved. And of course, I didn't take any pictures.

A year or more ago, I removed the screen to check for dirt on the screen and inside. Everything seemed very clean with almost no particles, so I didn't do much. Maybe I should take it off again and take a close look at the mirror that reflects the image onto the screen.

On my set there is no inspection port that allow you to view behind the screen; you have to remove the screen. That might be worth the effort and it is a lot less effort than removing the light engine. It seems like it has to be either a film on part of one of the mirrors or a source of light external to the LE.
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post #238 of 388 Old 03-22-2011, 07:15 AM - Thread Starter
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A defused area as that isn't on the screen. I also doubt it is on the mirror (especially since it is upside down). I never looked further past what I posted. I didn't want to take a chance and remove that circuit board for the iris.

It's a tough call.

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post #239 of 388 Old 03-27-2011, 04:47 PM
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Quote:
Originally Posted by videobruce View Post
A defused area as that isn't on the screen. I also doubt it is on the mirror (especially since it is upside down).
It's a tough call.
I found a diagram of the light path on Wikipedia that helps explain how light and dark pixels are created by tilting the micro mirrors. The picture isn't for a Mits TV, but it is probably close enough. I believe that there are either particles on the mirror or on the chip itself, or on the black light sink, that is causing light to go up the projection path when no light should theoretically be transmitted, i.e. when the mirror is tilted (during a black screen). The chip seems like the main culprit, but a dirty mirror would cause light to rattle around the compartment more than would occur with a clean mirror that directed most of the light onto the chip. Any excess light where it doesn't belong that can find a reflecting surface might end up going up the projection lens when it is not supposed to and cause the black level to be lighter than it should be.

I took a look again at the TV display when I had a black screen sent to it using monitortest.exe when our living room was very dark. There was more light than I would like to see for a black screen, but not a lot when you consider the intensity of the projection lamp. The fact that there is more on the part of the left side of the screen seems like there could be some particles unevenly distributed on the chip and even when the beam is deflected by the micro mirrors being tilted, the particles still reflect some light back into the projection lens.
Maybe it would help to clean the mirror, the display chip and the surrounding black surfaces, but I'm going to save it for another time. Just cleaning the lens above the display chip worked wonders and the risk probably isn't worth any improvement in the black level that might be reailzed (although I'd really like to fix it).

In the photo below, The red arrows show the light from the projection lens that passes through the color wheel and hits the mirror, where it is reflected onto the displaychip.
The yellow arrow shows the light being reflected into the projection lens when a micro mirror on the display chip is set to display a bright pixel.
The blue arrow shows the path that light takes when a micro mirror is tilted and a black pixel is desired. The light that takes the blue path has to hit a very black surface and be absorbed so it doesn't reflect around the cavity and end up in the yellow path, and finally onto the TV display screen.
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post #240 of 388 Old 03-28-2011, 04:48 AM - Thread Starter
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Interesting photo. Good find. I wonder what set this was taken from?

I assume that is the color wheel to the right, the DMD device at the bottom. I also assume the light path is to the rear of the main lens (black) with the interior lens behind it along with the internal mirror.

Abundant OTA television is what makes this country different from all others. Lets keep it this way.
The Internet is no place for streaming video.
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