The investigation comes after owners of the DLP projectors claimed that the lamps, which can cost over five hundred dollars to replace, were breaking after just a few months of service.

According to Toshiba documentation, the expected lifespan of a lamp for a Toshiba DLP television is between 6,000 and 8,000 hours depending on the brightness setting used by the television owner.

Toshiba DLP Rear Projection TV

A consumer who sets the brightness setting to High on their Toshiba DLP could expect a 6,000 hour lifespan whereas a consumer who set the brightness setting to low could extend the bulbs lifespan to about 8,000 hours.

Industry experts have said that those numbers are estimated under optimal conditions and under more normal usage conditions the typical lifespan of a lamp inside a DLP HDTV is between 3,000 and 5,000 hours. Experts tell us that the more you turn your DLP set on and off, the shorter the lifespan of the bulb. A bulb left on for long period of time will typically last more hours than one which is frequently  turned off an on  because it's the heating up and cooling down of the bulb which provides the greatest stress on the bulb.

Assuming the average television is on for four hours a day, a typical lamp should last two to year years and as much as four to six years using the optimal numbers.

The reality for many owners of Toshiba DLP televisions, was their bulbs were burning out in a matter of a few months.

In a discussion thread entitled How many hours on Toshiba DLP bulb when it blew?, which began in February, Digital Home members in Canada began asking one another how long the lamps on their Toshiba DLP televisions were lasting.

 The feedback was that bulbs lasted just three months.  Since that first post Digital Home has heard from more than 20 other readers who have had bulbs break prematurely. For example, member RendX's bulb lasted under 500 hours, Shieze's lasted 200 hours, DJDiggler's bulb lasted less than two months while scout543 had 305 hours on his bulb when it went dark. One member's bulb lasted a mere ten hours!

Calls to Toshiba Distributor Castel on the issue were not returned.