Optical Pyrometer is used for non-contact measurement of high temperatures of incandescent objects in the range 800°C to 1500°C. The temperature measurement makes use of visual comparison between the brightness of an electrically heated and calibrated incandescent filament (reference light bulb) in the Optical Pyrometer and that of the object to be measured. Once the brightness becomes same, the filament seems to disappear and the Temperature can be read on the LCD display.