Infrared thermometers measure temperature using blackbody radiation (generally infrared) emitted from objects,Infrared thermometers is a non-contact thermometers to measure temperature from a distance.The basic design consists of a lens to focus the infrared energy on to a detector, which converts the IR energy to an electrical signal that can be displayed in units of temperature after being compensated for ambient temperature variation,Infrared thermometers (IR) can be use in some critical conditions like Detecting clouds for remote telescope operation,Checking mechanical equipment or electrical circuit breaker boxes or outlets for hot spots,Checking heater or oven temperature, for calibration and control purposes,Detecting hot spots / performing diagnostics in electrical circuit board manufacturing,Checking for hot spots in fire fighting situations, This seminar gives you the basic working knowledge Infrared thermometers and its applications

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Introduction
Infrared thermometers measure temperature using blackbody radiation (generally infrared) emitted from objects. They are sometimes called laser thermometers if a laser is used to help aim the thermometer, or non-contact thermometers to describe the device’s ability to measure temperature from a distance. By knowing the amount of infrared energy emitted by the object and its emissivity, the object's temperature can be determined.
The most basic design consists of a lens to focus the infrared energy on to a detector, which converts the energy to an electrical signal that can be displayed in units of temperature after being compensated for ambient temperature variation. This configuration facilitates temperature measurement from a distance without contact with the object to be measured. As such, the infrared thermometer is useful for measuring temperature under circumstances where thermocouples or other probe type sensors cannot be used or do not produce accurate data for a variety of reasons.
Some typical circumstances are where the object to be measured is moving; where the object is surrounded by an electromagnetic field, as in induction heating; where the object is contained in avacuum or other controlled atmosphere; or in applications where a fast response is required.
 Infrared thermometers can be used to serve a wide variety of temperature monitoring functions. A few examples provided to this article include:
 Detecting clouds for remote telescope operation
 Checking mechanical equipment or electrical circuit breaker boxes or outlets for hot spots
 Checking heater or oven temperature, for calibration and control purposes
 Detecting hot spots / performing diagnostics in electrical circuit board manufacturing
 Checking for hot spots in fire fighting situations
 Monitoring materials in process of heating and cooling, for research and development or manufacturing quality control situations
There are many varieties of infrared temperature sensing devices available today, including configurations designed for flexible and portable handheld use, as well many designed for mounting in a fixed position to serve a dedicated purpose for long periods.
Specifications of portable handheld sensors available to the home user will include ratings of temperature accuracy (usually ±2°C/±4°F) and other parameters. The distance-to-spot ratio (D:S) is the ratio of the distance to the object and the diameter of the temperature measurement area. For instance if the D:S ratio is 12:1, measurement of an object 12 inches away will average the temperature over a 1-inch-diameter (25 mm) area. The sensor may have an adjustable emissivity setting, which can be set to measure the temperature of reflective (shiny) and non-reflective surfaces. A non-adjustable thermometer can be used to measure the temperature of a shiny surface by applying a non-shiny paint or tape to the surface.
The most usual infrared thermometers are the:
Spot Infrared Thermometer or Infrared Pyrometer, which measures the temperature at a spot on a surface (actually a relatively small area determined by the D:S ratio).
Related equipment, although not strictly thermometers, are:
Infrared Line Scanning Systems scan a larger area, typically by using what is essentially a spot thermometer pointed at a rotating mirror. These devices are widely used in manufacturing involving conveyors or "web" processes, such as large sheets of glass or metal exiting an oven, fabric and paper, or continuous piles of material along a conveyor belt.
Infrared Cameras are essentially infrared thermometers which measure the temperature at many points over a relatively large area to generate a two-dimensional image, called a thermogram, with each pixel representing a temperature. This technology is more processor- and software-intensive than spot or scanning thermometers, and is used for monitoring large areas. Typical applications include perimeter monitoring used by military or security personnel, inspection / process quality monitoring of manufacturing processes, and equipment or enclosed space hot or cold spot monitoring for safety and efficiency maintenance purposes. A photographic camera using infrared film and suitable lens, etc., is also called an infrared camera.

Reference:
http://en.wikipediawiki/Infrared_thermometer

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[attachment=9671]
NON CONTACT TEMPERATURE MEASUREMENT USING INFRARED RAYS
INTRODUCTION:
This project is based on VTU syllabus. The proposed system is based on ATMEL 89S52 µcontroller which is in our syllabus.
For doing this project we use some of the software like
 Embedded C for programming the application software to the microcontroller.
 Protel schematic software is used for designing the circuit diagram for this project.
 Express PCB software is used for designing the PCB for this project.
(Since PCB making is a big process and involves lot of machineries which are expensive, we are going to outsource this to the manufacturer.)
DESCRIPTION:
If we want to measure temperature of a heater it is difficult to go there and check the temperature. To solve this problem we can design a system that will help us to measure the temperature from a distance.
In this project we are using IR signal to transfer data from one place to other. The advantage of this type of measurement is that we can measure temperature from a distance. The temperature sensor will measure the temperature and the IR transmitter will transmit the corresponding temperature data. In the receiver section the IR receiver will receive this signal and the microcontroller decode it into temperature data and displays in to LCD.
TECHNOLOGY USED: IR technology.
PERCENTAGE OF SOFTWARE AND HARDWARE USED:
Embedded C: 40%
Microcontroller Hardware: 60%
COMPONENTS USED:
 Microcontroller : AT89S52.
 Memory EEPROM : AT24C04 (4kbyte)
 LCD : 2x16 characters
 Power Supply : 5V DC
 Buzzer : Freq-1 to 18Khz.Volt-5V-12VDC
 Temperature sensor : DS 1621
 IR Transmitter
 IR Receiver
SOFTWARE USED:
 Embedded C
WORKING PRINCIPLE:
This is very useful project for measuring temperature from distance. The main components used in this project are microcontroller, temperature sensor IC, IR transmitter and receiver.
The temperature sensor IC in this project is DS1621. This will supports a bidirectional 2–wire bus and data transmission protocol. The microcontroller will configure the IC for continuous temperature conversion by sending proper commands. After that microcontroller will sent command to start temperature conversion.
The temperature sensor IC measures the temperature and gives a 9 bit digital value. The microcontroller reads the data from temperature sensor IC and transferred to IR transmitter then it will transmit the IR signal corresponding to temperature.
In the receiver section has microcontroller, IR receiver and display system. The IR receiver receives the IR data and the microcontroller decodes it into temperature data and is displayed on LCD.
COMPONENT DESCRIPTION:
Power Supply:
The microcontroller and other devices get power supply from AC to Dc adapter through 7805, 5 volts regulator. The adapter output voltage will be 12V DC non regulated. The 7805/7812 voltage regulators are used to convert 12 V to 5V/12V DC.
Vital role of 7805 voltage regulator in ‘Non contact temperature measurement using infrared rays’
In this project 7805 regulator is used to regulate the unregulated adapter output voltage (9-12) into 5V.
Micro controller-AT89S52:
The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory. The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the industry- standard 80C51 instruction set and pin out.
Features
8K Bytes of In-System Programmable (ISP) Flash Memory
Endurance: 1000 Write/Erase Cycles
4.0V to 5.5V Operating Range
256 x 8-bit Internal RAM
32 Programmable I/O Lines
Full Duplex UART Serial Channel
Fully Static Operation: 0 Hz to 33 MHz
Vital role of Micro controller-AT89S52 in ‘Non contact temperature measurement using infrared rays’
In this project microcontroller reads digital data corresponding to temperature from ADC and convert it into temperature units and displayed on LCD.
TEMPERATURE SENSOR:
Description:
The DS1621 Digital Thermometer and Thermostat provides 9–bit temperature readings which indicate the temperature of the device. The thermal alarm output, TOUT, is active when the temperature of the device exceeds a user–defined temperature TH. The output remains active until the temperature drops below user defined temperature TL, allowing for any hysteresis necessary. User-defined temperature settings are stored in nonvolatile memory so parts may be programmed prior to insertion in a system. Temperature settings and temperature readings are all communicated to/from theDS1621 over a simple two–wire serial interface.
Features
– Temperature measurements require no external components
– Measures temperatures from –55°C to+125°C in 0.5°C increments.
– Fahrenheit equivalent is –67°F to 257°F in 0.9°F increments
– Temperature is read as a 9–bit value (2-byte transfer)
– Wide power supply range (2.7V to 5.5V)
– Converts temperature to digital word in 1second
– Thermostatic settings are user definable and nonvolatile
– Data is read from/written via a two–wire serial interface (open drain I/O lines)
– Applications include thermostatic controls, industrial systems, consumer products, thermometers, or any thermal sensitive system
– 8–pin DIP or SOIC package (150-MIL and 208-MIL).
Vital role of temperature sensor in ‘Non contact temperature measurement using infrared rays’
Temperature sensor is used to measure the temperature.
IR transmitter:
This IR led is used to emit the infrared rays at particular frequency. The emitting light is not visible in human eyes.
Vital role of IR transmitter in ‘Non contact temperature measurement using infrared rays’
In this project IR transmitter transmit the IR signal corresponding to temperature.