If it's all colors (Red, Blue, Green) doing the same thing at the same time, there are (unfortunately) multiple possibilities:
1) the AC to DC power supplies
2) the LED Driver Board
3) DLP driver, or DLP itself
The most likely problem is the DC-DC power supplies, which are known to have capacitors that go bad after several years of operation.
Due to this, there are many sources for either re-capacitor kits (DIY), or rebuilt power supplies with upgraded capacitors.
WARNING - Dangerous, and even lethal voltages are present inside your TV set. Do not attempt this unless you are trained in these kinds of repairs. Leave the TV unplugged for several hours (or preferably a full day) before attempting such.
DIAGNOSIS for bad capacitors: If you inspect the large capacitors on the power supply boards, and they are not totally FLAT across the top surface (if bulged at all), then you need a new power supply or new cap's. Likewise, if there is any leakage from the capacitors (usually a light-yellowish crusty appearing substance), they are BAD.
BP96-01726B ASSY PCB P-SMPS Aquamarin,LED DLP TV,DC2
Main power supply:
BP44-01001A SMPS-DLP TV PN082DPS-VF(A),AC/DC,90V-132
A quick Google search for these part number (BP96-01726B & BP44-01001A) will reveal many sources, and pictures to verify it's what your set has.