The projector lens improves the light utilization (make it more focus) and solves the problem of astigmatism.

透镜提升光源使用率（更加聚光），解决散光问题；

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Applicable to optical glass with high fineness and super-soft material such as LCD, ITO inductive glass, digital camera lens and projector lens.

主要应用于光洁度要求高及超软材质的光学玻璃如：LCD液晶显示，ITO导电玻璃，数码相机镜头、投影机镜头。

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If you are on the road and trying to get your projector set up in a hurry, this removes any doubt about the current position of the zoom lens, which can save you a few seconds.

如果你是出差使用并且想很快就把投影机架起来演示的话，关闭此功能可以无视镜头的变焦位置，从而可以节省一点时间。

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Runco's cutting edge sward didn't stop there as they have this new projector screen-mask that when paired with the proper equipment and lens on Runco projectors can display any aspect ratio.

ENGADGET: Runco @ CEDIA - 1080p projectors HD

Because many Blu-ray movies come in a 2.35:1 aspect ratio, which is wider than the projector's 16:9 aspect ratio, Panasonic's Intelligent Lens Memory automatically detects and switches the lens and focus position.

ENGADGET: Panasonic PT-AE8000U projector touts brighter, smoother 3D for king-of-the-hill home theaters

In addition to an infrared camera and projector, the Kinect features a microchip that performs "skeletal tracking, " or following movement without using a camera lens.

WSJ: A New Game for Microsoft's Kinect