Continued from [Solar Phone Teardown] Charging Performance Tested [Part 2]
In the previous article, we checked the usability of the solar cell module equipped in the Solar Phone SH002, which KDDI released as one of its summer 2009 models of the au brand mobile phones. Then, we moved on to break down the display unit incorporating the solar cell module.
The SH002 features waterproof property that complies with IPX5/IPX7 standards. Therefore, we expected that it would be more difficult to disassemble the handset compared with other mobile phones.
The display unit is composed without screws, and its cover is attached by using double-faced tape. We inserted a flat-blade screwdriver between the chassis and the cover to remove the cover and check the solar cell module.
Next, we began to take out the solar cell module, which was fixed on the frame together with 1.1-inch black-and-white electronic paper. On the back of the module, there were electrodes probably for grounding, and they were connected to metal part on the back side of the frame. The module might produce electromagnetic noise.
Furthermore, we took out the solar cell module from the frame. The module measures 67.5 x 41.0 x 0.8mm and weighs about 4g. Its back is printed with two marks, "Sharp" (manufacturer) and "LR0GC01" (model number). The LR0GC01 has the same dimensions as the "LR0GC02," the solar cell module that Sharp announced for mobile phones in May 2009 (See related article).
"The LR0GC02 has almost the same specifications as the LR0GC01, but it's a different model," the company said. "Also, it is possible to change the electrode pattern on the surface of the module."
Maybe, they have different electrode structures.
The chassis and the cover on the side of the LCD panel were firmly attached to each other with double-faced tape. In general, there are two methods to realize waterproof property. One is double-faced tape, and the other is waterproof gaskets.
"Double-faced tape ensures a high waterproof property but makes it difficult to rework the internal design in the case of an accident," said an engineer from a Japanese handset manufacturer.

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