a device that takes a picture of visual information and changes it into a form that a computer can store and show on its screen

The optical reader scans number plates and compares them against stolen vehicles. 光学读取器扫描车牌，并与被盗车辆进行比较。

Optical data readers can be used to scan a document and make sense of the patterns it finds within the document. 光学数据读取器可用于扫描文件，并识别其在文件中发现的模式。

Some devices, such as optical mark readers, enable data to be entered directly, without human intervention. 有些设备，如光学标记读取器，可以直接输入数据，无需人工干预。