能实现如下功能：

1）天黑时灯亮，利用光敏二极管的阻值变化，控制可控硅的导通

（2）天亮时，利用光敏二极管的阻值变小，控制可控硅的断路，使灯熄灭。（3）或用继电器空盒子等的开、关-1) when it gets dark, with light activated diode lights the resistance changes, control of silicon controlled conduction

(2) when morning, with light activated diode resistance of the smaller, control of silicon controlled, to cause the lamp to break out.

(3) or by relays empty box of such as open and close