Washington, D.C. (March 4, 2010) -- Panasonic has been hit with a class action suit regarding claims that the picture quality on its Plasma HDTVs has been declining.

According to CNET.com, the lawsuit, which was filed February 12 in federal court in Newark, New Jersey, claims an increase in the brightness of the black levels of the Plasma sets. Additionally, the defendants are charging that the sets are showing a decrease in their contrast ratios.

If true, the higher black level and lower contrast ratio would dilute the picture quality of the sets.

CNET says the suit states that "the television is no longer producing the same image quality that (Panasonic) represented it would produce."

The technology web site writes that it tested two 2009 model Panasonic Plasma sets and found a declining performance.

When asked about the test, Panasonic issued the following statement to CNET:

"Unfortunately, after our discussions about providing you with further information, a lawsuit regarding this issue was filed. While we believe that the lawsuit is baseless, since this is now a matter in litigation, Panasonic company policy prohibits us from responding to your questions."

The picture quality issue first surfaced at Internet message boards when Panasonic owners complained that their sets were under performing.

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