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Infrared Thermometer using Arduino

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Infrared Thermometer using Arduino project is one of most essential project which you should definitely try making at home as price of thermometers are very high in recent days.

Before getting into project let’s get into basic ideology behind this project.

What is Infrared Thermometer using Arduino

In general thermometer is a device use to measure temperature which can be from Body, Home various other appliances and the purpose of measurement is for monitoring heat.

Problems with conventional Thermometers

In Conventional thermometer measurement output will be digital or so called analog if its filled with mercury and only work on physical contact with its sensor known as probe.

Suppose if we need to measure temperature of human body probe should be kept on desired part. Wait for some time until readings are finalized.

But with these type of measurement device there are lots of problems involved.

Problems explained by taking an example

Suppose a person suffering from fever gets his/hers temp checked later if some other person gets his temp checked there is high chance of infection.

Even though the probe might be sterilized it takes some time to completely disinfect

Hence keeping this in mind idea was originated to create non contact based temperature measurement system.

Easy and cheapest way of doing this was using Arduino board with inexpensive infrared temperature sensor known as MLX 90614.

So coming out of behind the scenes! for this project lets talk about necessary supplies requirement.

  • Arduino Uno also nano works fine for this project
  • MLX 90614 aka infrared temperature sensor
  • Display module 2×16 characters
  • Arduino IDE and Usb connector

Circuit Diagram for Infrared Thermometer using Arduino

Infrared Thermometer using Arduino circuit diagram
Infrared Thermometer using Arduino

Circuit Diagram Details

MLX 90614 has 4 pins 2 for power supply and other 2 for signal supply, Vin and Gnd for positive and negative power supply while Scl and Sda for signal transmission and receiving.

16×2 Display module has pins in same format, here Vcc and Gnd for power input and output where as other two pin for data sending and receiving.

Arduino Uno with Scl pins from both the sensors are connect to A5 in same way A6 pin is for other end signal pins.

After these connections are complete we can upload code to board, Just copy and paste this code into your IDE and upload.

Code for Arduino Infrared Thermometer

#include <Wire.h>
#include <Adafruit_MLX90614.h>
#include <LiquidCrystal_I2C.h>
Adafruit_MLX90614 mlx = Adafruit_MLX90614();
//Define I2C address of liquid crystal display, number of columns and rows
LiquidCrystal_I2C lcd(0x3F, 16, 2);
double temp_amb;
double temp_obj;
void setup()
Serial.println(“Temperature Sensor MLX90614”);
//Initialize LCD I2C
//Initialize MLX90614
void loop()
temp_amb = mlx.readAmbientTempC();
temp_obj = mlx.readObjectTempC();
if(temp_obj > 37) {
Serial.print(“Warning…HIGH TEMP…”);
lcd.print(“HIGH TEMP…”);
//lcd display
lcd.setCursor(0, 0);
lcd.print(“Room Temp:”);
lcd.setCursor(10, 0);
lcd.setCursor(15, 0);
lcd.setCursor(0, 1);
lcd.print(“Body Temp:”);
lcd.setCursor(10, 1);
lcd.setCursor(15, 1);
//Serial Monitor
Serial.print(“Room Temp = “);
Serial.print(“Object temp = “);

After this code is done uploading we can use this project, just use usb power source to power uno board.

How to use Infrared Thermometer using Arduino

After the device is powered to on display module starts to show measurements of room temperature this can be use as reference/standard for measurements.

To measure temp of body just place temp sensor in front of body and wait for few seconds, Just check temperature that is shown below room temp on display module, this is required temp.

Video tutorial

Full tutorial on how to make this thermometer can be found here

Hope you liked this project idea, Try to make this wonderful project and if you face any problems let me know, Thanks.

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