I recently bought a Hitachi P42H401 (1080i). When I connect a computer to it horizontal lines flicker, also text is not sharp. This TV cannot be returned, and I don't notice these problem when watching movies or playing games, I'm mostly content with it.

I'm trying to better inform myself. If anything below is incorrect feel free to let me know. These observations are just my best guesses.

I was recently reading and article about the difference between 1080i and 1080p. Something that I did not realize is that 1080i displays aren't truly interlaced! It's frustrating to know that they're called interlaced in light of this information. Horizontal lines flicker because they're only drawn on the display every other cycle. On the cycles the lines aren't drawn, the pixel above or below is "doubled up", or some other scaling technique done by the computer in the TV.

My TV is 1080i, so I assume its native resolution is 1920 x 1080. My TV is then scaling the interlaced 1920x1080 signal to a progressive one. A 1080p TV would actually have to do less processing since it doesn't have to scale the image which means it requires less powerful hardware. A 1080p signal does require double the bandwidth so I'm not sure if that negates my previous statement. So is the difference between my 1080i TV and an equivalent 1080p TV a limitation in it's software?

If all the above assumptions are correct, it makes me wonder if it's possible to hack a 1080i tv into a 1080p tv.

Your display is 1024x1080 1.3 mil pix. A true 1080p display is 1920x1080 2.1 mill pix. There is no software that is going to make up for the loss of 800k pix.

I'm annoyed with the way my TV has been marketed. I'm also annoyed with myself for not making myself better informed. Arg.

Horizontal lines flicker because they're only drawn on the display every other cycle. On the cycles the lines aren't drawn, the pixel above or below is "doubled up", or some other scaling technique done by the computer in the TV. .
Isn't that what interlacing is? :confused:

Isn't that what interlacing is? :confused:

See this article (http://www.hometheaterhifi.com/volume_14_1/feature-article-1080p-3-2007-part-2.html) for better info.

Here's my understanding.

A true 1080i TV should look identical to a 1080p TV if there is no movement. The flicker I see is there even with a still image.

No Plasma or LCD is a true interlace display, they all show a progressive image. The signal may be interlaced, but the display cannot show it without scaling. In my case, the flicker is caused when the TV scales the 1080i signal (effectively 1920x540) to the progressive image that is actually displayed (1024x1080).

You have on of those "odd, early, and now discontinued plasma models" the article mentioned. Obviously, the "discontinued" part is not quite correct. Hitachi still makes them. It's called ALiS (Alternate Lighting of Surfaces), or at least was until recently. I read somewhere that Hitachi was dropping the term. The technology was jointly developed with Fujitsu when they were in a joint venture a few years ago. Fujitsu still uses a form of it in their 55" model.

I have my computer hooked up to the P42H401, no flickering.. try playing around with the settings.