One Channel IR sensor is a multipurpose sensor Board. The Board consists of IR LED and photo diode as IR receiver. As we all know that Infra rays are directional rays in the invisible spectrum range. Since it is directional, this can be easily used for obstacle sensing, path break, alignment purpose etc. The invisible spectrum range makes it user to hide the presence of sensor.
The Board gives two outputs. Digital outputs can be easily interfaced with other digital circuits or microcontroller Boards. The digital output of board can be adjusted with a Threshold level. A resistor pot on the board is provided for triggering the sensor level at different sensitivity. Another output on the board is analog output. The Analog output is the most effective and advanced way of using this sensor board. The analog output varies in the range of 0 to 5V. The analog output increase as the obstacle reflects the transmitted IR rays batch to the photo diode. The strength of reflected wave reduces as the object moves away from the sensor. This one channel IR Sensor is used as distance measurement tool in the range of 5 to 10cm effectively. The one channel IR sensor board analog output is connected with ADC block of microcontroller. If you are using 8051 microcontroller, then a separate ADC like ADC0809 or ADC0804 can be used as Intermediate converts of Analog to digital.