| 摘要 |
A light sensing system comprises a first light sensor (21′), a second light sensor (21) and a first light shielding material (24) disposed over the first light sensor (21′) but not over the second light sensor (21) so as to block ambient light from being incident on the first light sensor (21). A first electrically conductive material (23a) is disposed between the first light shielding layer (24) and the first light sensor and a second electrically conductive material (23b) is disposed over the second light sensor. The second electrically conductive material (23b) is at least partially light-transmissive. Providing the first electrically conductive material (23a) between the first light shielding layer (24) and the first light sensor eliminates any parasitic capacitance that would otherwise be set up by the light shielding layer (24) (which is typically a metallic layer). Providing the second electrically conductive material (23b) over the second light sensor ensures that the two light sensors are as closely electrically matched to one another as possible. Thus, a difference between the output of the first light sensor and the output of the second light sensor may reliably be taken as an indication of the level of ambient light. The first electrically conductive material (23a) and the second electrically conductive material (23b) may be provided by disposing a layer of electrically conductive material, which is at least partially light-transmissive, so as to cover both light sensors.
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