PURPOSE: To eliminate need for a preparatory operation for a measurement and to detect a leakage part accurately, easily and in a short time by a method wherein a liquid crystal is modulated optically by heat generated on a chip and a heated part of an integrated circuit chip is detected.

CONSTITUTION: A heated-part analyzer contains the following: a polarizing microscope 1 which contains a polarizing plate 7 and a analyzer plate 6 at its inside and which is fit with an eyepiece 5 and an objective 8; an integrated circuit chip 3 which is placed on a board 4 and which is coated with a liquid crystal; a tester 2 which is connected, via a cable 9, to the board 4 where the integrated circuit chip 3 has been placed. The polarizing microscope 1 is installed on a tester station 10, and an arbitrary pattern is checked while a logic operation from the tester main body 2 to the chip 3 is being executed. A state of the chip is observed via a monitor TV 12 after a monitor camera 11 has been installed on an eyepiece part of the polarizing microscope 1.