Step 1- Choosing Your Lcd

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Step 1- Choosing Your Lcd

hertzblaster
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hertzblaster
Advanced Member
Joined: September 27th, 2004, 5:28 pm

October 5th, 2008, 4:40 pm #1

THIS WAS WRITTEN OCT 6,2008 . I DID MODIFICATION ON THE STATEMENTS WRITTEN HERE AS OF JAN 5,2013 INDICATED BY THE BLUE TEXT. SO MUCH HAVE CHANGE SINCE THAT TIME!

Consideration choosing the right LCD for your need.

A> LCD size

DIY projector normally is bigger than commercial projector. Size normally is the first issue.

1. If size is not an issue, then there are alot of cheap used LCD out there with digonal size of 15 inches with xga resolution, very good enough to project high definition images.

2. If size is a problem, then its gonna take alot of effort to get compatible LCD. But if you have the money to spend, you can easily buy on line. Smaller LCD like 8.4 inch diagonal normally has SVGA resolution, few are xga resolution which are very expensive say around $250 on line.
Smaller 5.6 inch and 7 inch LCD with 1280x800 is now easily available and affordable. 10.1 inch model now has 1920x1200 and is also affordable.

In the pics below, the black box is the box for my 8.4 inch lcd and the bigger one is the box for my 15ich lcd. Beside them is the chair for comparison. Those boxes, I believe can still be made smaller by 30-50% based on your design.

Check out sample of newer design here http://z6.invisionfree.com/diyprojectorphi...927&st=50&#last

B> LCD resolution

1. XGA Resolution (1024x768 pixel) A bigger LCD say 15 inches and above has xga resoluiton which are capable enough to display high definition images. Smaller LCD with XGA resolution are expensive.

2. SVGA resolution (800x600 pixels) - DVD disk has a resolution of 720x480 pixels so if you have an lcd with svga resolution, it can display the full resolution of dvd players which can display very good images (xga of course is alot better)

3. VGA resolution (640x480) - If you are really low on budget, some small lcd has vga resolution. this can still project good images though your projected image size will be limited otherwise you will see screendoor effect(pixelated) and washout images.

It is not recommended anymore to use lcd with resolution lower than vga resolution.

1920x1200 and 1280x800 small lcd are now available

C> LCD inputs

1. VGA input - Never buy the lcd without vga input (computer video cable) . VGA input can display progressive output from your sources like pc and component output ( need transcoder to convert to vga) of dvd player .

2. HDMI/DVI (digital input) - Some lcd models have DVI input which is very good because some dvd players have dvi output. Very few lcd have HDMI input. DVI/HDMI peforms better than vga interface because it will bypass the A/D converter from dvd players, pc, and lcd monitor. The lesser electronics used, the better is the image quality.

Composite input/ s-video of dvd players only displays 720x240 pixels so avoid using this as much as possible. Remember VGA interface is the minimum requirements.

Controller with TV, HDMI,VGA,DVI,component and audio video input are now available.

D> LCD aspect ratio

1. 4:3 aspect ratio- It has the same aspect ratio of regular TV. In the old days, most of the movies are 4:3 so no problem in displaying the correct image size. But nowadays, most movies are widescreen (1.77:1)or letterbox format ( 2.35:1). So you will see black bars in top and bottom of your image. You will lose up to 60% of lcd resolution when you use widescreen and letterbox movies so image quality will go down.

2. 16:9 aspect ratio- When you play 4:3 aspect ratio movie, you will see black bars at the two sides. But nowadays, widescreen are prevalent and you will use full resolution of your lcd and image quality will be better than when using 4:3 aspect ratio lcd.

E> Contrast Ratio - This is other lcd specification that can make lcd cheap or expensive ( the other one is resolution). Higher contrast say more than 1000 can produce beautiful images than with lcd with lower resoltuion. Contrast is the difference in intensity of white and black.

F> Response time- Lower lcd response time means lcd can display moving images smoothly. try to get lcd with response time not higher than 25ms . The lower, the better

G> Number of colors- Look for lcd with 16.7million colors to give accurate color rendition. colors with 262k is also good but will not be displaying the real color.
Pls try to avoid sending PM to me . Send me email instead hertzblaster@hotmail.com .

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hertzblaster
Advanced Member
hertzblaster
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Joined: September 27th, 2004, 5:28 pm

November 2nd, 2008, 9:09 am #2

You must make sure that the lcd is compatible. You can check out this site for compatible lcd
http://www.baseportal.com/cgi-bin/ba.../Lumenlab/main

I uses LG L1553s which currently is available in the local market and has the best specs for 15 icnh lcd. Bought mine used for 4500 pesos.
Check out the Build guide for new build.http://z6.invisionfree.com/diyprojectorphils/index.php?act=SC&c=554547


Compatible lcd only has one circuit board attached to the longer side of lcd panel.







Another lcd compatible model



Only the lcd panel is needed. the backlight will be left behind and is of no use for this project. SO if somebody sell lcd with broken backlight, it will probably sell cheap.

Incompatible lcd. Notice that there is a circuit board at the left side and connected by 90 deg flat cable to the other circuit board. This cable is what makes this lcd incomaptible. But if you are good in modding/soldering, then its ok.
The control board and OSD board is connected by ordinary cable and is long enough to be put out of the way of the lcd.



Another incompatible lcd model

Pls try to avoid sending PM to me . Send me email instead hertzblaster@hotmail.com .

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