①Facial recognition technology is widely used today. For example, police use it to search for bad guys. It's also used to unlock phones or doors. Now, a similar technology, known as facial detection (探测), is entering a new field: the business of advertising.
②Such systems are going through tests in a small number of stores. One facial detection system can judge a person's "happiness" or "fear" level. That helps businesses see how people feel as they look at products or advertisements in the store. Another system can detect whether someone is wearing eyeglasses. If so, stores can send advertisements for new glasses to him.
③Facial detection technology is also placed inside some large advertising boards. Cameras in those boards can detect information like people's ages and five levels of feelings-from "very happy" to "very unhappy".
④Supporters of the technology say it could improve buyers' experience by showing products they might like or by offering them products at lower prices.
⑤Some are against the idea of using such systems. Pam Dixon， the head of a privacy (隐 私) group， is one of them. She thinks______▲____. For example, a business could raise the price of a product according to a person's age and feelings.
⑥However, one store testing the technology explained they wouldn't store people's information like 'names or ages. And the advertising board system maker said it didn't keep any personal information or record any videos.
