It is necessary to clean the lens of ViewSonic projector periodically. Because the lens tend to accumulate dust and then impact the projection effect.
Never rub the lens with abrasive materials, in case of causing some irreverable damage to the lens. And avoid spraying or pouring any liquid directly onto the case. Handle the projector with care, as a darker-colored projector, if scuffed, may show marks more clearly than a lighter-colored projector.
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