That is not enough to light up anything more than an 80 diagonal screen in a fully darkened room.

这是不够的，任何点亮在一个完全黑暗的房间比80屏幕的对角线上。

youdao

Device that superficially resembles a large iPod with an 8-inch diagonal screen, lacks a keyboard, packs USB and FireWire ports and runs Mac OS X along with a variety of multimedia goodies.

这是一台表面类似于大号iPod的设备，它具有8英寸屏幕，没有键盘，装有usb和FireWire端口，运行Mac OS X操作系统并且支持各种多媒体。

youdao

Dot is measured in millimeters (mm), and indicates the diagonal distance between same-colored phosphor dots on the screen.

像素点以毫米为单位，表示屏幕上相同颜色的磷光点之间的对角线距离。

youdao

The iPad has a touch-screen that is just under 25 centimeters in diagonal.

VOA: standard.2010.04.03

By contrast, an iMac with a comparable 20-inch diagonal screen weighs in at just 20 pounds.

FORBES: The iMac From Texas

The 15-inch viewable diagonal screen is nearly comparable to a 17-inch conventional CRT monitor's true display area.

CNN: The LCD-monitor face off

The Kindle Fire has a 7-inch diagonal screen compared to the nearly 10-inch screen on the iPad.

WSJ: Clues to Apple's Post-Jobs Direction in iPad Event