Frequently it has a hinged glass cover to hold copy flat, and may have a removable section in which a transparency holder can be positioned for back-lighting illumination.

一般都备有铰链着的玻璃盖面，以把稿件夹平。有些更可以换上透明片架，在后面打灯照明。

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Premium glass is utilizied on the back cover with a polarized glass pattern that offers a clean, modern look.

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