reversing a lcd flat panel with composite video input

[rolo95]

Hi

I need to find a way to reverse ( mirror ) the image on a flat panel lcd tv
i dont have any tv now but i will get one

If somebody can steer me in the right direction

i heard that you can change the chipset state of a pin from low to high or viceversa

or if there is any tv model that already have that function i will appreciate your help

Thank You
Rolo.

 

[Nigel Goodwin]

Some of the old 4:3 Sharp sets allowed you to do that - but I've not seen a modern set that does. CRT sets were easy, just reverse the line scan coils.

 

[rolo95]

Some of the old 4:3 Sharp sets allowed you to do that - but I've not seen a modern set that does. CRT sets were easy, just reverse the line scan coils.

Hey nigel
thanks for your reply man

yeah.. i need a flat lcd not a crt
actually we are replacing old crt's no longer made and with a 15" lcd tv i can do it
but.... if they dont got the invering function i need to find a way to do it...

any ideas or what model of tv to get and find the chipset papers to see if there is a pin
we can tweak or something

also i have one broken lcd pc panel open apart and i see that the wires that go directly to the LCD screen itself have like 25 wires
maybe one pair of those can be reversed.... i dont know if the LCD screen principle is the same as the crt regarding the scan lines
Thanks
Rolo.

 

[Nigel Goodwin]

Unless the set is designed to do it, it's doubtful you could modify it - they don't have handy pins you can connect - it's more likely a function of the software.

 

[rolo95]

I have found this
Winmate---Industrial LCD Display, Panel pc, industrial pc, Digital Signage, Marine LCD,HMI & rugged tablet pc, Rugged pc, panel mount PC & LCD, rugged mobile pc


and This

LCD Controller Cards: Products - Digital View
the SVH-1920

 

[joemartz]

Rolo I think this is what you are looking for. Very useful information included here. The LCD controller circuit is key. However, as the article states, manufacturers are not following any kind of convention. Every one does their own thing so it get really difficult. So, what you need to do is find a panel controller that offers the mirror feature you want to use and then find out what sets use it. The easiest way would be to call the controller manufacturer and ask them which panels carry that controller that has the feature you want. Since the article mentions the Sharp LH79520, I would start there. You know who this is, so get some sleep! LOL

Sharp: TFT LCD Interface Signals

Sharp: TFT LCD Interface Signals

 

[Sceadwian]

**broken link removed**
hmm... only 600 dollars =O

Is there any reason you can't do the mirroring optically with an actual mirror? It'd be much simpler than doing it electrically.

 

[blueroomelectronics]

Just curious why anyone would want to mirror a video image?

 

[Nigel Goodwin]

Just curious why anyone would want to mirror a video image?

Presumably because he wants to reflect it in a mirror. Like I said earlier, it was a common feature on early Sharp 4:3 LCD's - bit confusing if you accidentally hit the button on the remote though!

 

[rolo95]

Rolo I think this is what you are looking for. Very useful information included here. The LCD controller circuit is key. However, as the article states, manufacturers are not following any kind of convention. Every one does their own thing so it get really difficult. So, what you need to do is find a panel controller that offers the mirror feature you want to use and then find out what sets use it. The easiest way would be to call the controller manufacturer and ask them which panels carry that controller that has the feature you want. Since the article mentions the Sharp LH79520, I would start there. You know who this is, so get some sleep! LOL

Sharp: TFT LCD Interface Signals

Sharp: TFT LCD Interface Signals

Looks nice Joe

will keep digging on it...

 

[rolo95]

Just curious why anyone would want to mirror a video image?

That is key for a teleprompter application

Teleprompter - Wikipedia, the free encyclopedia

and that is i am looking for since i lost one teleprompter CRT
and i want to replace it with a LCD one...

But i need the FLIP function on it

Hope the WIKI clarify your doubts
Rolo.

 

[Hero999]

What about using a PC with a TV capture card?

Surely it can then be done using software?

Maplin sells them and you can get digital TV cards.
**broken link removed**

 

[Sceadwian]

I still don't get why you need to do this on the electrical side. If you're already going through the effort to put a mirror in there for the teleprompter then adding a second one to reverse the mirroring effect will only slightly change the size. Doing this with a PC tuner card and software to mirror the pixels is incredibly complex and expensive compared to... one more piece of aluminized glass.

 

[rolo95]

I still don't get why you need to do this on the electrical side. If you're already going through the effort to put a mirror in there for the teleprompter then adding a second one to reverse the mirroring effect will only slightly change the size. Doing this with a PC tuner card and software to mirror the pixels is incredibly complex and expensive compared to... one more piece of aluminized glass.

Old CRT teleprompters are Heavier and Bulkier
now that we have lost one and there is no CRT replacement by the orig manufacturer
we want to find a LCD solution...

we have 3 cameras that will be modded to LCD
however the costs of 3000+ USD for a Broadcast Ready Teleprompter
is prohibitive for our TV station

So... we need to find an " Alternative" solution to those 3000+ Units (each)

also if you look at the top right pic on here Teleprompter - Wikipedia, the free encyclopedia
you will see why we cant add another mirror to the equation
not to say the astethic part of it

It it simply not cost effective, those 2 way mirrors are expensive, we already got them

Just we need a source that projects a flipped image of the video... Simple.

Capisch ?

 

[Sceadwian]

Then the link I provided above for 600 dollars for a NTSC video signal mirroring device should be very attractive. It's a 500% cost reduction. If you want cheaper, then you have to be willing to put the work into the device, either way it's going to cost to proportionately the same.

 

[joemartz]

Why you cant use a mirror for this application...

I still don't get why you need to do this on the electrical side. If you're already going through the effort to put a mirror in there for the teleprompter then adding a second one to reverse the mirroring effect will only slightly change the size. Doing this with a PC tuner card and software to mirror the pixels is incredibly complex and expensive compared to... one more piece of aluminized glass.

The teleprompter application is a very unique situation. The camera must see through the glass that is reflecting the image of the screen. The glass is mounted in front of the lens at a 45 degree angle and the lens is enclosed within the teleprompter assembly so that light does not come trough the glass from the camera side. The glass measures approximately 20 inches by 20 inces. The screen is mounted below the lens in such a manner that the person in front of the lens (the talent) can see the reflection of the screen on the glass. We at home dont even see the glass or the reflection. It really isnt a 2 way mirror and it can't be because of the optical properties needed. The 2 way mirror would tend to change these to unacceptable levels. So, in order to keep the talent from having to learn to read backwards and right to left, we the engineers reverse the video so that when it is reflected it appears left to right. I wish I had come up with the original idea. But then again that would make me around 100 years old huh? Anyway, I hope this clears things up for you. If not,this picture might help.

**broken link removed**

 

[joemartz]

Forgot to mention the pins

Looks nice Joe

will keep digging on it...

Rolo, sorry man, I forgot to mention that the pin to look at was pin 30. The Horizontal Display Direction Select Signal is set to Low for normal display and High for Right to Left or reverse. Sorry about that. Just scroll down to the LH79520's LCD Interface Pin Assignments.

Sharp: TFT LCD Interface Signals

 

[joemartz]

Then the link I provided above for 600 dollars for a NTSC video signal mirroring device should be very attractive. It's a 500% cost reduction. If you want cheaper, then you have to be willing to put the work into the device, either way it's going to cost to proportionately the same.

That is definitely a very cool find. Thanks Seadwian. Rolo will have to total out the price for everything. He needs to replace the CRT style monitor with a LCD panel since the CRT parts are no longer available. He will also need to build some sort of custom mount for the camera pedestal to hold the LCD panel. But that is definitely an option. Since his studio system uses 3 cameras with a teleprompter on each, he can use that one device feeding a Video DA for all 3.

 

[3lectrokid]

if the data is coming from the computer there is generally an option to flip the monitor around. look inside the graphics card program or right click the graphics card in the system launch bar (bottom right) and look for a flip option

 

[rolo95]

if the data is coming from the computer there is generally an option to flip the monitor around. look inside the graphics card program or right click the graphics card in the system launch bar (bottom right) and look for a flip option

It is analog composite video