[LCD TVs Teardown] Structure of Samsung's Backlight Unit [Part 4]

Jun 11, 2009
Nikkei Electronics Teardown Squad
The LCD panel module being disassembled
The LCD panel module being disassembled
[Click to enlarge image]
The logo of Samsung Electronics found on the back of the backlight unit
The logo of Samsung Electronics found on the back of the backlight unit
[Click to enlarge image]
There are four pieces of optical sheets.
There are four pieces of optical sheets.
[Click to enlarge image]
The number of CCFLs is 12.
The number of CCFLs is 12.
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The power supply board (top), the signal processing board (left) and the tuner circuit board (right)
The power supply board (top), the signal processing board (left) and the tuner circuit board (right)
[Click to enlarge image]

Continued from [LCD TVs Teardown] What's inside $500 32-inch TV? [Part 3]

Nikkei Electronics Teardown Squad took off the back chassis of the DY-32SDDB, Dynaconnective's low-priced LCD TV. Of course, it was too early to wrap up the teardown. We began to dig into the internal structure of the backlight unit inside the LCD panel module, which the company purchased from Samsung Electronics at a low cost.

First, we examined the optical elements mounted in the backlight unit. They are a diffuser panel, a lens sheet and two pieces of diffuser sheets.

"This is very typical of LCD TVs," said an engineer from a backlight manufacturer. However, he added, "It's surprising to see a lens sheet in this LCD TV."

Normally, lens sheets are used to enhance the luminance of backlights.

"Some LCD panel modules in low-priced TVs consist of a diffuser panel and two pieces of diffuser sheets," the engineer said. "This time, the lens sheet was used probably to improve the luminance."

Next, we checked the light source of the backlight. It has 12 CCFLs (cold cathode fluorescent lamps) of 3mm in diameter. Compared with the Bravia KDL-32J5, Sony's energy-saving LCD TV, the diameter of the CCFL is smaller and its number is larger.

"Until a few years ago, we could see the same design in TVs made by Japanese manufacturers," an engineer from a backlight manufacturer said.

Considering the fact that Dynaconnective purchased the panels in stock from Samsung Electronics at a low price, it is unlikely that Dynaconnective decided specifications of the panel. Probably, it used LCD panel modules mass-produced by Samsung Electronics.

Dynaconnective seems to have made other efforts to cut costs than procuring panels at a low cost. There are many parts manufactured by Franco-Italian STMicroelectronics on the signal processing board and the tuner circuit board, where major functions of the LCD TV are integrated.

"To save the time to design the product and cut costs, reference designs of STMicroelectronics probably were adopted without making many changes to them," said an engineer from a TV manufacturer.