用光电元件作敏感元件的光电传感器，其种类繁多，用途广泛。按光电传感器的输出量性质可分为两类：（1 ）把被测量转换成连续变化的光电流而制成的光电测量仪器，可用来测量光的强度以及物体的温度、透光能力、位移及表面状态等物理量。例如：测量光强的照度计，光电高温计，光电比色计和浊度计，预防火灾的光电报警器，构成检查被加工零件的直径、长度、椭圆度及表面粗糙度等自动检测装置和仪器，其敏感元件均用光电元件。半导体光电元件不仅在民用工业领域中得到广泛的应用，在军事上更有它重要的地位。例如用硫化铅光敏电阻可做成红外夜视仪、红外线照相仪及红外线导航系统等；（2 ）把被测量转换成继续变化的光电流。利用光电元件在受光照或无光照射时" 有" 或"无"电信号输出的特性制成的各种光电自动装置。光电元件用作开关式光电转换元件。例如电子计算机的光电输入器，开关式温度调节装置及转速测量数字式光电测速仪等。
There are many kinds of photoelectric sensors using photoelectric elements as sensing elements, and they are widely used. According to the output quality of photoelectric sensor, it can be divided into two categories: (1) The photoelectric measuring instrument, which converts the measured value into the continuously changing photoelectric current, can be used to measure the intensity of light and the physical quantities such as temperature, transmittance, displacement and surface state of the object. For example, Illuminometers for measuring light intensity, photoelectric pyrometers, photoelectric colorimeters and turbidimeters, photoelectric alarms for preventing fires, constitute automatic detection devices and instruments for inspecting the diameter, length, ellipticity and surface roughness of machined parts, and their sensitive elements are all photoelectric components. Semiconductor www.buxiugangsanton.cnwww.buxiugangwanto.cnwww.panshiganzaoj.cnwww.ganzaoji.net.cn www.shengwuzhi.net.cnwww.dingjingxiangjiao.cnoptoelectronic devices are not only widely used in civil industry, but also play an important role in military affairs. For example, the lead sulfide photoresistor can be used to make infrared night vision, infrared camera and infrared navigation system, etc. (2) The measured value is converted into continuous changing photocurrent. A variety of photoelectric automatic devices are made by using the characteristics of "yes" or "no" electrical signal output of photoelectric elements when illuminated or not illuminated. Photoelectric elements are used as switching photoelectric conversion elements. For example, the photoelectric input of the computer, the switching temperature regulator and the digital photoelectric tachometer for speed measurement, etc.