IR Sensor Module
The Multipurpose Infrared Sensor is an add-on for your Line Follower Robot Arduino and obstacle avoiding robot that gives your robot the ability to detect lines or nearby objects. The sensor works by detecting reflected light coming from its own infrared LED. By measuring the amount of reflected infrared light, it can detect light or dark (lines) or even objects directly in front of it. An onboard RED LED is used to indicate the presence of an object or detect the line. The sensing range is adjustable with an inbuilt variable resistor. (find out a wide range of Sensor at solicstores.in)
The IR sensor module consists mainly of the IR Transmitter and Receiver, Opamp, Variable Resistor (Trimmer pot), output LED.
IR LED Transmitter
IR LED emits light, in the range of Infrared frequency. IR light is invisible to us as its wavelength (700nm – 1mm) is much higher than the visible light range. IR LEDs have a light-emitting angle of approx. 20-60 degree and range of approx. few centimeters to several feet, it depends upon the type of IR transmitter and the manufacturer. Some transmitters have the range in kilometers. IR LED white or transparent in color, so it can give out the amount of maximum light.
Photodiode acts as the IR receiver as it conducts when light falls on it. The photodiode is a semiconductor that has a P-N junction, operated in Reverse Bias, which means it starts conducting the current in reverse direction when Light falls on it, and the amount of current flow is proportional to the amount of Light. This property makes it useful for IR detection. Photodiode looks like a LED, with a black color coating on its outer side, Black color absorbs the highest amount of light.
LM393 is a two independent precision voltage comparator is used as voltage comparator in the IR sensor. the comparator will compare the threshold voltage set using the preset (pin2) and the photodiode’s series resistor voltage (pin3).
Photodiode’s series resistor voltage drop > Threshold voltage = Opamp output is High.
Photodiode’s series resistor voltage drop < Threshold voltage = Opamp output is Low.
When Opamp’s output is high the LED at the Opamp output terminal turns ON (Indicating the detection of Object).
The variable resistor used here is preset. It is used to calibrate the distance range at which an object should be detected.
The 5 VDC supply input is given to the VCC pin and the supply negative is connected to the GND terminal of the module. When no object is detected within the range of the IR receiver, the output LED remains off.
When an object is detected within the range of the IR sensor the LED glows.
IR Sensor Module Pinout
The module features a 3 wire interface with Vcc, GND and an OUTPUT pin on its tail. It works fine with 3.3 to 5V levels. Upon hindrance/reflectance, the output pin gives out a digital signal (a low-level signal). The onboard preset helps to fine-tune the range of operation, effective distance range is 2cm to 80cm.
IR Sensor Module Features
- 5VDC Operating voltage
- I/O pins are 5V and 3.3V compliant
- The effective distance range of 2cm to 80cm
- Adjustable Sensing range
- Built-in Ambient Light Sensor
- 20mA supply current
- Mounting hole
- Proximity Sensor
- Item Counter
- Obstacle Detection
- Industrial safety devices
- Wheel encoder
- Burglar Alarm
Package Includes :
1 x IR Infrared Obstacle Avoidance Sensor Module