I have found in the 8 years of being online, and providing answers/solutions to people's computer problems; that coming across, and trying to explain the answer/solution, is the hardest thing to do.
It appears I have failed you
Let's try again;
1) Perusing the internet, I look at what LCD screens are offered, (Aspire 4315 series of Notebook PC's), and see what backlighting is offered.
I have seen LCD screen examples offered, that seem to be CCFL backlighting.
I DO have to know however, WHAT style of backlighting is used for YOUR laptop.
Do Not want to make a mistake here, because the mistake could cost you five times as much.
You buy a not needed LCD screen, about $100, and only needed a screen Inverter; about $18.
IF, your laptop states LED backlighting, THEN the only option is to buy the entire LCD screen.
With LED backlighting, the LED backlighting is incorporated into the LCD screen assembly.
There is no simply replace the LED backlighting.
With a laptop that uses CCFL for backlighting, the first thing to do is replace the screen Inverter.
90 PERCENT OF THE TIME the fault is a bad screen Inverter.
Allow me to state the primer over again, now that I have more room;
An LCD screen does Not produce light,http://solutions.3m.com/wps/portal/3M/en_US/NA_Optical/Systems/BehindTheScenes/Optics101/
(Click on the monitor icon)
Therefore an LCD screen needs an additional light source.
A Backlight is the additional light source.
A Backlight can be a CCFL, (Or two of them), Or a series of LED's.
(Light Emitting Diode)
When I state series, I mean a LOT of LED's. They are incorporated into the LCD screen assembly.
(You see from the above link that an LCD screen is an assembly)
A CCFL is a Cold Cathode Fluorescent Lamp. (Bulb)
Similar to Fluorescent lighting used in homes, and businesses, but on a MUCH smaller scale.
Average thickness is 2mm. That is a little larger than 1/16th of an Inch.
Average length is almost as long, as the LCD screen is in height,http://www.laptoprepair101.com/laptop/2007/12/09/replace-laptop-backlight-ccfl-lamp/
View the last 8 photos to see what an average CCFL looks like.
Know this also; A CCFL is a Fluorescent bulb.
This means it has MERCURY in it.
VERY dangerous if the bulb breaks!
Mercury is POISON to the human body.
IF, it is determined that the laptop uses CCFL/s for a Backlight, -> AND the CCFL/s are bad, I implore you to have a pro change it/them.
The other option would be to replace the LCD screen.
The CCFL is incorporated into the LCD screen assembly.
HOWEVER, I still go with the screen Inverter is bad.
(IF, the laptop uses CCFL for a Backlight)
Go to the 'paragraph' that starts with Aspire 1200. (1200 in Blue)
Drop down to the 4th line, (3810T in blue), scroll across, and click on - 4315
This is a free Service Manual.
It is in PDF file form.
The computer you are using now has Adobe Reader on it, which uses PDF files.
After you click on the file name (4315) it may take up to 30 seconds, before the first page comes up.
(The file is downloading in the background)
[May be on my end, but it took 44 seconds just now, and using a medium speed DSL connection. Usually takes 10 to 12 seconds. Just letting you know so you do not think the link doesn't work ]
LCD Module Disassembly Process - Page 86
Hmmm, also states Inverter Board. (screen Inverter)
Removing the LCD Module is on Page 71.
4) NOT an Acer Aspire 4315 series of Notebook PC; Aspire 3810T. Posted so you would be able to get a more 'Hands on' idea, of working on your laptop,http://www.insidemylaptop.com/replace-broken-screen-acer-aspire-3810t-laptop/
Test the screen Inverter before replacing?
IF you have a sensitive multimeter, you can. Otherwise IMHO the choice is to just replace the screen Inverter.
Parts changing I know, and I abhor it; but if it is your only choice?http://www.fonerbooks.com/test.htm
Where in the Philippines to order from? Do not know.
Suggest using the internet.
For additional questions please post in a Comment.