PURPOSE: To accurately and easily know the tilt angle of a sample by creating a pair of bright lines inclined in proportion to the tilt angle of the sample on a phosphor plate and comparing them with the scale on a transparent angle dial which is provided closely to the front face of a phosphor screen.

CONSTITUTION: A cathode-ray tube 14 is of an electromagnetic deflection type and is provided with horizontal and vertical deflection coils 12 and 13. The horizontal deflection coil 12 is connected to the slider 2a of a cosine resistor 2 and a current detection resistor 10 through a deflection amplifier 8. On the other hand, the vertical deflection coil 13 is connected to the slider 3a of a sine resistor 3 and a current deflection resistor 11 through a deflection amplifier 9. Since a cosine signal and a sine signal are applied to the horizontal deflection coil 12 and the vertical deflection coil 13, of a cathode-ray tube 14 respectively in the same phase, a pair of bright lines with the tilt angle which is proportional to that of the sample are displayed on the phosphor screen 4a of the cathode-ray tube 14.