| 摘要 |
A projecting device with a keystone correction function includes an adjustable part, a signal generator, a correction circuit and a micro-processing control unit. The adjustable part is coupled to a supporting foot of the projecting device, and an electric property thereof changes along with a different height of the supporting foot. When an angle of the projecting device is adjusted, the signal generator generates and outputs a corresponding adjusting signal serving as a basis for the keystone correction according to the electric property of the adjustable part. In practice, the adjustable part may be achieved by utilizing a rheostat, and the signal generator may be achieved by utilizing a biasing circuit and a converter. When an angle is adjusted, a resistance of the rheostat is also adjusted simultaneously so that the biasing circuit outputs different voltages to generate the adjusting signal.
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